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https://github.com/EnterpriseDB/repmgr.git
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bd58e4128c
If repmgrd is promoting the local node, it was only logging the contents of "promote_command" at DEBUG level; it would be useful to see this at the default log level. Related to GitHub #473.
2985 lines
82 KiB
C
2985 lines
82 KiB
C
/*
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* repmgrd-physical.c - physical (streaming) replication functionality for repmgrd
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*
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* Copyright (c) 2ndQuadrant, 2010-2018
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <signal.h>
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#include "repmgr.h"
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#include "repmgrd.h"
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#include "repmgrd-physical.h"
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typedef enum
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{
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FAILOVER_STATE_UNKNOWN = -1,
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FAILOVER_STATE_NONE,
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FAILOVER_STATE_PROMOTED,
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FAILOVER_STATE_PROMOTION_FAILED,
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FAILOVER_STATE_PRIMARY_REAPPEARED,
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FAILOVER_STATE_LOCAL_NODE_FAILURE,
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FAILOVER_STATE_WAITING_NEW_PRIMARY,
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FAILOVER_STATE_REQUIRES_MANUAL_FAILOVER,
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FAILOVER_STATE_FOLLOWED_NEW_PRIMARY,
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FAILOVER_STATE_FOLLOWING_ORIGINAL_PRIMARY,
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FAILOVER_STATE_NO_NEW_PRIMARY,
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FAILOVER_STATE_FOLLOW_FAIL,
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FAILOVER_STATE_NODE_NOTIFICATION_ERROR
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} FailoverState;
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typedef enum
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{
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ELECTION_NOT_CANDIDATE = -1,
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ELECTION_WON,
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ELECTION_LOST,
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ELECTION_CANCELLED
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} ElectionResult;
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static PGconn *upstream_conn = NULL;
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static PGconn *primary_conn = NULL;
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static FailoverState failover_state = FAILOVER_STATE_UNKNOWN;
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static int primary_node_id = UNKNOWN_NODE_ID;
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static t_node_info upstream_node_info = T_NODE_INFO_INITIALIZER;
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static NodeInfoList sibling_nodes = T_NODE_INFO_LIST_INITIALIZER;
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static ElectionResult do_election(void);
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static const char *_print_election_result(ElectionResult result);
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static FailoverState promote_self(void);
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static void notify_followers(NodeInfoList *standby_nodes, int follow_node_id);
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static void check_connection(t_node_info *node_info, PGconn **conn);
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static bool wait_primary_notification(int *new_primary_id);
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static FailoverState follow_new_primary(int new_primary_id);
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static FailoverState witness_follow_new_primary(int new_primary_id);
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static void reset_node_voting_status(void);
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static bool do_primary_failover(void);
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static bool do_upstream_standby_failover(void);
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static bool do_witness_failover(void);
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static void update_monitoring_history(void);
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static const char * format_failover_state(FailoverState failover_state);
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void
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handle_sigint_physical(SIGNAL_ARGS)
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{
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PGconn *writeable_conn;
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PQExpBufferData event_details;
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initPQExpBuffer(&event_details);
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appendPQExpBuffer(&event_details,
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"%s signal received",
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postgres_signal_arg == SIGTERM
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? "TERM" : "INT");
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if (local_node_info.type == PRIMARY)
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writeable_conn = local_conn;
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else
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writeable_conn = primary_conn;
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create_event_notification(writeable_conn,
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&config_file_options,
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config_file_options.node_id,
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"repmgrd_shutdown",
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true,
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event_details.data);
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termPQExpBuffer(&event_details);
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terminate(SUCCESS);
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}
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/* perform some sanity checks on the node's configuration */
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void
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do_physical_node_check(void)
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{
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/*
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* Check if node record is active - if not, and `failover=automatic`, the
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* node won't be considered as a promotion candidate; this often happens
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* when a failed primary is recloned and the node was not re-registered,
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* giving the impression failover capability is there when it's not. In
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* this case abort with an error and a hint about registering.
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*
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* If `failover=manual`, repmgrd can continue to passively monitor the
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* node, but we should nevertheless issue a warning and the same hint.
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*/
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if (local_node_info.active == false)
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{
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char *hint = "Check that \"repmgr (primary|standby) register\" was executed for this node";
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switch (config_file_options.failover)
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{
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/* "failover" is an enum, all values should be covered here */
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case FAILOVER_AUTOMATIC:
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log_error(_("this node is marked as inactive and cannot be used as a failover target"));
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log_hint(_("%s"), hint);
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close_connection(&local_conn);
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create_event_notification(NULL,
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&config_file_options,
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config_file_options.node_id,
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"repmgrd_shutdown",
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false,
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"node is inactive and cannot be used as a failover target");
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terminate(ERR_BAD_CONFIG);
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case FAILOVER_MANUAL:
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log_warning(_("this node is marked as inactive and will be passively monitored only"));
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log_hint(_("%s"), hint);
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break;
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}
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}
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if (config_file_options.failover == FAILOVER_AUTOMATIC)
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{
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/*
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* Check that "promote_command" and "follow_command" are defined, otherwise repmgrd
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* won't be able to perform any useful action in a failover situation.
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*/
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bool required_param_missing = false;
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if (config_file_options.promote_command[0] == '\0')
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{
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log_error(_("\"promote_command\" must be defined in the configuration file"));
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if (config_file_options.service_promote_command[0] != '\0')
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{
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/*
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* "service_promote_command" is *not* a substitute for "promote_command";
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* it is intended for use in those systems (e.g. Debian) where there's a service
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* level promote command (e.g. pg_ctlcluster).
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*
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* "promote_command" should either execute "repmgr standby promote" directly, or
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* a script which executes "repmgr standby promote". This is essential, as the
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* repmgr metadata is updated by "repmgr standby promote".
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*
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* "service_promote_command", if set, will be executed by "repmgr standby promote",
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* but never by repmgrd.
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*
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*/
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log_hint(_("\"service_promote_command\" is set, but can only be executed by \"repmgr standby promote\""));
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}
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required_param_missing = true;
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}
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if (config_file_options.follow_command[0] == '\0')
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{
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log_error(_("\"follow_command\" must be defined in the configuration file"));
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required_param_missing = true;
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}
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if (required_param_missing == true)
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{
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log_hint(_("add the missing configuration parameter(s) and start repmgrd again"));
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close_connection(&local_conn);
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exit(ERR_BAD_CONFIG);
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}
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}
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}
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/*
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* repmgrd running on the primary server
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*/
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void
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monitor_streaming_primary(void)
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{
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instr_time log_status_interval_start;
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PQExpBufferData event_details;
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reset_node_voting_status();
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initPQExpBuffer(&event_details);
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appendPQExpBuffer(&event_details,
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_("monitoring cluster primary \"%s\" (node ID: %i)"),
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local_node_info.node_name,
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local_node_info.node_id);
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/* Log startup event */
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if (startup_event_logged == false)
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{
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create_event_notification(local_conn,
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&config_file_options,
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config_file_options.node_id,
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"repmgrd_start",
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true,
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event_details.data);
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startup_event_logged = true;
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}
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else
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{
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create_event_notification(local_conn,
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&config_file_options,
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config_file_options.node_id,
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"repmgrd_reload",
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true,
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event_details.data);
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}
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log_notice("%s", event_details.data);
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termPQExpBuffer(&event_details);
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INSTR_TIME_SET_CURRENT(log_status_interval_start);
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local_node_info.node_status = NODE_STATUS_UP;
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while (true)
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{
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/*
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* TODO: cache node list here, refresh at `node_list_refresh_interval`
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* also return reason for inavailability so we can log it
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*/
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if (is_server_available(local_node_info.conninfo) == false)
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{
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/* local node is down, we were expecting it to be up */
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if (local_node_info.node_status == NODE_STATUS_UP)
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{
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PQExpBufferData event_details;
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instr_time local_node_unreachable_start;
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INSTR_TIME_SET_CURRENT(local_node_unreachable_start);
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initPQExpBuffer(&event_details);
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appendPQExpBuffer(&event_details,
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_("unable to connect to local node"));
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log_warning("%s", event_details.data);
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local_node_info.node_status = NODE_STATUS_UNKNOWN;
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close_connection(&local_conn);
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/*
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* as we're monitoring the primary, no point in trying to
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* write the event to the database
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*
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* XXX possible pre-action event
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*/
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create_event_notification(NULL,
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&config_file_options,
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config_file_options.node_id,
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"repmgrd_local_disconnect",
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true,
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event_details.data);
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termPQExpBuffer(&event_details);
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local_conn = try_reconnect(&local_node_info);
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if (local_node_info.node_status == NODE_STATUS_UP)
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{
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int local_node_unreachable_elapsed = calculate_elapsed(local_node_unreachable_start);
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initPQExpBuffer(&event_details);
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appendPQExpBuffer(&event_details,
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_("reconnected to local node after %i seconds"),
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local_node_unreachable_elapsed);
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log_notice("%s", event_details.data);
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create_event_notification(local_conn,
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&config_file_options,
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config_file_options.node_id,
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"repmgrd_local_reconnect",
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true,
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event_details.data);
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termPQExpBuffer(&event_details);
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goto loop;
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}
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monitoring_state = MS_DEGRADED;
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INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
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log_notice(_("unable to connect to local node, falling back to degraded monitoring"));
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}
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}
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if (monitoring_state == MS_DEGRADED)
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{
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int degraded_monitoring_elapsed = calculate_elapsed(degraded_monitoring_start);
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if (config_file_options.degraded_monitoring_timeout > 0
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&& degraded_monitoring_elapsed > config_file_options.degraded_monitoring_timeout)
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{
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initPQExpBuffer(&event_details);
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appendPQExpBuffer(&event_details,
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_("degraded monitoring timeout (%i seconds) exceeded, terminating"),
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degraded_monitoring_elapsed);
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log_notice("%s", event_details.data);
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create_event_notification(NULL,
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&config_file_options,
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config_file_options.node_id,
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"repmgrd_shutdown",
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true,
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event_details.data);
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termPQExpBuffer(&event_details);
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terminate(ERR_MONITORING_TIMEOUT);
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}
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log_debug("monitoring node in degraded state for %i seconds", degraded_monitoring_elapsed);
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if (is_server_available(local_node_info.conninfo) == true)
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{
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local_conn = establish_db_connection(local_node_info.conninfo, false);
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if (PQstatus(local_conn) != CONNECTION_OK)
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{
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log_warning(_("node appears to be up but no connection could be made"));
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close_connection(&local_conn);
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}
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else
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{
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local_node_info.node_status = NODE_STATUS_UP;
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/* check to see if the node has been restored as a standby */
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if (get_recovery_type(local_conn) == RECTYPE_STANDBY)
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{
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PGconn *new_primary_conn;
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initPQExpBuffer(&event_details);
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appendPQExpBuffer(&event_details,
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_("reconnected to node after %i seconds, node is now a standby, switching to standby monitoring"),
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degraded_monitoring_elapsed);
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log_notice("%s", event_details.data);
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termPQExpBuffer(&event_details);
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primary_node_id = UNKNOWN_NODE_ID;
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new_primary_conn = get_primary_connection_quiet(local_conn, &primary_node_id, NULL);
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if (PQstatus(new_primary_conn) != CONNECTION_OK)
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{
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close_connection(&new_primary_conn);
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log_warning(_("unable to connect to new primary node %i"), primary_node_id);
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}
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else
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{
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RecordStatus record_status;
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log_debug("primary node id is now %i", primary_node_id);
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record_status = get_node_record(new_primary_conn, config_file_options.node_id, &local_node_info);
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if (record_status == RECORD_FOUND)
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{
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bool resume_monitoring = true;
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log_debug("node %i is registered with type = %s",
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config_file_options.node_id,
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get_node_type_string(local_node_info.type));
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/*
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* node has recovered but metadata not updated - we can do that ourselves,
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*/
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if (local_node_info.type == PRIMARY)
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{
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log_notice(_("node \"%s\" (ID: %i) still registered as primary, setting to standby"),
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config_file_options.node_name,
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config_file_options.node_id);
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if (update_node_record_set_active_standby(new_primary_conn, config_file_options.node_id) == false)
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{
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resume_monitoring = false;
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}
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else
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{
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record_status = get_node_record(new_primary_conn, config_file_options.node_id, &local_node_info);
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if (record_status != RECORD_FOUND)
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{
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resume_monitoring = false;
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}
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}
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}
|
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|
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if (resume_monitoring == true)
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{
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monitoring_state = MS_NORMAL;
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log_notice(_("former primary has been restored as standby after %i seconds, updating node record and resuming monitoring"),
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degraded_monitoring_elapsed);
|
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|
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initPQExpBuffer(&event_details);
|
|
|
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appendPQExpBuffer(&event_details,
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_("node restored as standby after %i seconds, monitoring connection to upstream node %i"),
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degraded_monitoring_elapsed,
|
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local_node_info.upstream_node_id);
|
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create_event_notification(new_primary_conn,
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&config_file_options,
|
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config_file_options.node_id,
|
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"repmgrd_standby_reconnect",
|
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true,
|
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event_details.data);
|
|
|
|
|
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termPQExpBuffer(&event_details);
|
|
|
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close_connection(&new_primary_conn);
|
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|
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/* restart monitoring as standby */
|
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return;
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}
|
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}
|
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else if (record_status == RECORD_NOT_FOUND)
|
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{
|
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PQExpBufferData event_details;
|
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initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
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_("no metadata record found for this node on current primary %i"),
|
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primary_node_id);
|
|
|
|
log_error("%s", event_details.data);
|
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log_hint(_("check that 'repmgr (primary|standby) register' was executed for this node"));
|
|
|
|
close_connection(&new_primary_conn);
|
|
|
|
create_event_notification(NULL,
|
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&config_file_options,
|
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config_file_options.node_id,
|
|
"repmgrd_shutdown",
|
|
false,
|
|
event_details.data);
|
|
termPQExpBuffer(&event_details);
|
|
|
|
terminate(ERR_BAD_CONFIG);
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
monitoring_state = MS_NORMAL;
|
|
|
|
initPQExpBuffer(&event_details);
|
|
appendPQExpBuffer(&event_details,
|
|
_("reconnected to primary node after %i seconds, resuming monitoring"),
|
|
degraded_monitoring_elapsed);
|
|
|
|
create_event_notification(local_conn,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_local_reconnect",
|
|
true,
|
|
event_details.data);
|
|
|
|
log_notice("%s", event_details.data);
|
|
termPQExpBuffer(&event_details);
|
|
goto loop;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* possibly attempt to find another node from cached list check if
|
|
* there's a new primary - if so add hook for fencing? loop, if
|
|
* starts up check status, switch monitoring mode
|
|
*/
|
|
}
|
|
loop:
|
|
/* emit "still alive" log message at regular intervals, if requested */
|
|
if (config_file_options.log_status_interval > 0)
|
|
{
|
|
int log_status_interval_elapsed = calculate_elapsed(log_status_interval_start);
|
|
|
|
if (log_status_interval_elapsed >= config_file_options.log_status_interval)
|
|
{
|
|
log_info(_("monitoring primary node \"%s\" (node ID: %i) in %s state"),
|
|
local_node_info.node_name,
|
|
local_node_info.node_id,
|
|
print_monitoring_state(monitoring_state));
|
|
|
|
if (monitoring_state == MS_DEGRADED)
|
|
{
|
|
log_detail(_("waiting for the node to become available"));
|
|
}
|
|
|
|
INSTR_TIME_SET_CURRENT(log_status_interval_start);
|
|
}
|
|
}
|
|
|
|
if (got_SIGHUP)
|
|
{
|
|
log_debug("SIGHUP received");
|
|
|
|
if (reload_config(&config_file_options))
|
|
{
|
|
close_connection(&local_conn);
|
|
local_conn = establish_db_connection(config_file_options.conninfo, true);
|
|
|
|
if (*config_file_options.log_file)
|
|
{
|
|
FILE *fd;
|
|
|
|
fd = freopen(config_file_options.log_file, "a", stderr);
|
|
if (fd == NULL)
|
|
{
|
|
fprintf(stderr, "error reopening stderr to \"%s\": %s",
|
|
config_file_options.log_file, strerror(errno));
|
|
}
|
|
}
|
|
}
|
|
got_SIGHUP = false;
|
|
}
|
|
|
|
log_verbose(LOG_DEBUG, "sleeping %i seconds (parameter \"monitor_interval_secs\")",
|
|
config_file_options.monitor_interval_secs);
|
|
|
|
sleep(config_file_options.monitor_interval_secs);
|
|
}
|
|
}
|
|
|
|
|
|
void
|
|
monitor_streaming_standby(void)
|
|
{
|
|
RecordStatus record_status;
|
|
instr_time log_status_interval_start;
|
|
PQExpBufferData event_details;
|
|
|
|
reset_node_voting_status();
|
|
|
|
log_debug("monitor_streaming_standby()");
|
|
|
|
/*
|
|
* If no upstream node id is specified in the metadata, we'll try and
|
|
* determine the current cluster primary in the assumption we should
|
|
* connect to that by default.
|
|
*/
|
|
if (local_node_info.upstream_node_id == UNKNOWN_NODE_ID)
|
|
{
|
|
local_node_info.upstream_node_id = get_primary_node_id(local_conn);
|
|
|
|
/*
|
|
* Terminate if there doesn't appear to be an active cluster primary.
|
|
* There could be one or more nodes marked as inactive primaries, and
|
|
* one of them could actually be a primary, but we can't sensibly
|
|
* monitor in that state.
|
|
*/
|
|
if (local_node_info.upstream_node_id == NODE_NOT_FOUND)
|
|
{
|
|
log_error(_("unable to determine an active primary for this cluster, terminating"));
|
|
close_connection(&local_conn);
|
|
exit(ERR_BAD_CONFIG);
|
|
}
|
|
}
|
|
|
|
record_status = get_node_record(local_conn, local_node_info.upstream_node_id, &upstream_node_info);
|
|
|
|
/*
|
|
* Terminate if we can't find the record for the node we're supposed to
|
|
* monitor. This is a "fix-the-config" situation, not a lot else we can
|
|
* do.
|
|
*/
|
|
if (record_status == RECORD_NOT_FOUND)
|
|
{
|
|
log_error(_("no record found for upstream node (ID: %i), terminating"),
|
|
local_node_info.upstream_node_id);
|
|
log_hint(_("ensure the upstream node is registered correctly"));
|
|
close_connection(&local_conn);
|
|
exit(ERR_DB_CONN);
|
|
}
|
|
else if (record_status == RECORD_ERROR)
|
|
{
|
|
log_error(_("unable to retrieve record for upstream node (ID: %i), terminating"),
|
|
local_node_info.upstream_node_id);
|
|
close_connection(&local_conn);
|
|
exit(ERR_DB_CONN);
|
|
}
|
|
|
|
log_debug("connecting to upstream node %i: \"%s\"", upstream_node_info.node_id, upstream_node_info.conninfo);
|
|
|
|
upstream_conn = establish_db_connection(upstream_node_info.conninfo, false);
|
|
|
|
/*
|
|
* Upstream node must be running at repmgrd startup.
|
|
*
|
|
* We could possibly have repmgrd skip to degraded monitoring mode until
|
|
* it comes up, but there doesn't seem to be much point in doing that.
|
|
*/
|
|
if (PQstatus(upstream_conn) != CONNECTION_OK)
|
|
{
|
|
log_error(_("unable connect to upstream node (ID: %i), terminating"),
|
|
local_node_info.upstream_node_id);
|
|
log_hint(_("upstream node must be running before repmgrd can start"));
|
|
|
|
close_connection(&local_conn);
|
|
exit(ERR_DB_CONN);
|
|
}
|
|
|
|
/*
|
|
* refresh upstream node record from upstream node, so it's as up-to-date
|
|
* as possible
|
|
*/
|
|
record_status = get_node_record(upstream_conn, upstream_node_info.node_id, &upstream_node_info);
|
|
|
|
if (upstream_node_info.type == STANDBY)
|
|
{
|
|
/*
|
|
* Currently cascaded standbys need to be able to connect to the
|
|
* primary. We could possibly add a limited connection mode for cases
|
|
* where this isn't possible.
|
|
*/
|
|
primary_conn = establish_primary_db_connection(upstream_conn, false);
|
|
|
|
if (PQstatus(primary_conn) != CONNECTION_OK)
|
|
{
|
|
log_error(_("unable to connect to primary node"));
|
|
log_hint(_("ensure the primary node is reachable from this node"));
|
|
exit(ERR_DB_CONN);
|
|
}
|
|
|
|
log_verbose(LOG_DEBUG, "connected to primary");
|
|
}
|
|
else
|
|
{
|
|
primary_conn = upstream_conn;
|
|
}
|
|
|
|
primary_node_id = get_primary_node_id(primary_conn);
|
|
|
|
/* Log startup event */
|
|
if (startup_event_logged == false)
|
|
{
|
|
PQExpBufferData event_details;
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("monitoring connection to upstream node \"%s\" (node ID: %i)"),
|
|
upstream_node_info.node_name,
|
|
upstream_node_info.node_id);
|
|
|
|
create_event_notification(primary_conn,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_start",
|
|
true,
|
|
event_details.data);
|
|
|
|
startup_event_logged = true;
|
|
|
|
log_info("%s", event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
}
|
|
|
|
monitoring_state = MS_NORMAL;
|
|
INSTR_TIME_SET_CURRENT(log_status_interval_start);
|
|
upstream_node_info.node_status = NODE_STATUS_UP;
|
|
|
|
while (true)
|
|
{
|
|
log_verbose(LOG_DEBUG, "checking %s", upstream_node_info.conninfo);
|
|
if (is_server_available(upstream_node_info.conninfo) == false)
|
|
{
|
|
/* upstream node is down, we were expecting it to be up */
|
|
if (upstream_node_info.node_status == NODE_STATUS_UP)
|
|
{
|
|
instr_time upstream_node_unreachable_start;
|
|
|
|
INSTR_TIME_SET_CURRENT(upstream_node_unreachable_start);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
upstream_node_info.node_status = NODE_STATUS_UNKNOWN;
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("unable to connect to upstream node \"%s\" (node ID: %i)"),
|
|
upstream_node_info.node_name, upstream_node_info.node_id);
|
|
|
|
/* */
|
|
if (upstream_node_info.type == STANDBY)
|
|
{
|
|
/* XXX possible pre-action event */
|
|
create_event_record(primary_conn,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_upstream_disconnect",
|
|
true,
|
|
event_details.data);
|
|
}
|
|
else
|
|
{
|
|
/* primary connection lost - script notification only */
|
|
create_event_record(NULL,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_upstream_disconnect",
|
|
true,
|
|
event_details.data);
|
|
}
|
|
|
|
log_warning("%s", event_details.data);
|
|
termPQExpBuffer(&event_details);
|
|
|
|
close_connection(&upstream_conn);
|
|
|
|
/*
|
|
* if local node is unreachable, make a last-minute attempt to reconnect
|
|
* before continuing with the failover process
|
|
*/
|
|
|
|
if (PQstatus(local_conn) != CONNECTION_OK)
|
|
{
|
|
check_connection(&local_node_info, &local_conn);
|
|
}
|
|
|
|
upstream_conn = try_reconnect(&upstream_node_info);
|
|
|
|
/* Node has recovered - log and continue */
|
|
if (upstream_node_info.node_status == NODE_STATUS_UP)
|
|
{
|
|
int upstream_node_unreachable_elapsed = calculate_elapsed(upstream_node_unreachable_start);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("reconnected to upstream node after %i seconds"),
|
|
upstream_node_unreachable_elapsed);
|
|
log_notice("%s", event_details.data);
|
|
|
|
create_event_notification(upstream_conn,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_upstream_reconnect",
|
|
true,
|
|
event_details.data);
|
|
termPQExpBuffer(&event_details);
|
|
|
|
goto loop;
|
|
}
|
|
|
|
/* still down after reconnect attempt(s) */
|
|
if (upstream_node_info.node_status == NODE_STATUS_DOWN)
|
|
{
|
|
bool failover_done = false;
|
|
|
|
if (upstream_node_info.type == PRIMARY)
|
|
{
|
|
failover_done = do_primary_failover();
|
|
}
|
|
else if (upstream_node_info.type == STANDBY)
|
|
{
|
|
failover_done = do_upstream_standby_failover();
|
|
}
|
|
|
|
/*
|
|
* XXX it's possible it will make sense to return in all
|
|
* cases to restart monitoring
|
|
*/
|
|
if (failover_done == true)
|
|
{
|
|
primary_node_id = get_primary_node_id(local_conn);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (monitoring_state == MS_DEGRADED)
|
|
{
|
|
int degraded_monitoring_elapsed = calculate_elapsed(degraded_monitoring_start);
|
|
|
|
if (config_file_options.degraded_monitoring_timeout > 0
|
|
&& degraded_monitoring_elapsed > config_file_options.degraded_monitoring_timeout)
|
|
{
|
|
initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("degraded monitoring timeout (%i seconds) exceeded, terminating"),
|
|
degraded_monitoring_elapsed);
|
|
|
|
log_notice("%s", event_details.data);
|
|
|
|
create_event_notification(NULL,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_shutdown",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
terminate(ERR_MONITORING_TIMEOUT);
|
|
}
|
|
|
|
|
|
log_debug("monitoring node %i in degraded state for %i seconds",
|
|
upstream_node_info.node_id,
|
|
degraded_monitoring_elapsed);
|
|
|
|
if (is_server_available(upstream_node_info.conninfo) == true)
|
|
{
|
|
upstream_conn = establish_db_connection(upstream_node_info.conninfo, false);
|
|
|
|
if (PQstatus(upstream_conn) == CONNECTION_OK)
|
|
{
|
|
/* XXX check here if upstream is still primary */
|
|
/*
|
|
* -> will be a problem if another node was promoted in
|
|
* the meantime
|
|
*/
|
|
/* and upstream is now former primary */
|
|
/* XXX scan other nodes to see if any has become primary */
|
|
|
|
upstream_node_info.node_status = NODE_STATUS_UP;
|
|
monitoring_state = MS_NORMAL;
|
|
|
|
if (upstream_node_info.type == PRIMARY)
|
|
{
|
|
primary_conn = upstream_conn;
|
|
}
|
|
else
|
|
{
|
|
if (primary_conn == NULL || PQstatus(primary_conn) != CONNECTION_OK)
|
|
{
|
|
primary_conn = establish_primary_db_connection(upstream_conn, false);
|
|
}
|
|
}
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("reconnected to upstream node %i after %i seconds, resuming monitoring"),
|
|
upstream_node_info.node_id,
|
|
degraded_monitoring_elapsed);
|
|
|
|
create_event_notification(primary_conn,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_upstream_reconnect",
|
|
true,
|
|
event_details.data);
|
|
|
|
log_notice("%s", event_details.data);
|
|
termPQExpBuffer(&event_details);
|
|
|
|
goto loop;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* unable to connect to former primary - check if another node
|
|
* has been promoted
|
|
*/
|
|
|
|
NodeInfoListCell *cell;
|
|
int follow_node_id = UNKNOWN_NODE_ID;
|
|
|
|
/* local node has been promoted */
|
|
if (get_recovery_type(local_conn) == RECTYPE_PRIMARY)
|
|
{
|
|
log_notice(_("local node is primary, checking local node state"));
|
|
|
|
/*
|
|
* It's possible the promote command timed out, but the promotion itself
|
|
* succeeded. In this case failover state will be FAILOVER_STATE_PROMOTION_FAILED;
|
|
* we can update the node record ourselves and resume primary monitoring.
|
|
*/
|
|
if (failover_state == FAILOVER_STATE_PROMOTION_FAILED)
|
|
{
|
|
int degraded_monitoring_elapsed;
|
|
int former_upstream_node_id = local_node_info.upstream_node_id;
|
|
|
|
update_node_record_set_primary(local_conn, local_node_info.node_id);
|
|
record_status = get_node_record(local_conn, local_node_info.node_id, &local_node_info);
|
|
|
|
degraded_monitoring_elapsed = calculate_elapsed(degraded_monitoring_start);
|
|
|
|
log_notice(_("resuming monitoring as primary node after %i seconds"),
|
|
degraded_monitoring_elapsed);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
appendPQExpBuffer(&event_details,
|
|
"promotion command failed but promotion completed successfully");
|
|
create_event_notification(local_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_promote",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
/* notify former siblings that they should now follow this node */
|
|
get_active_sibling_node_records(local_conn,
|
|
local_node_info.node_id,
|
|
former_upstream_node_id,
|
|
&sibling_nodes);
|
|
notify_followers(&sibling_nodes, local_node_info.node_id);
|
|
|
|
/* this will restart monitoring in primary mode */
|
|
monitoring_state = MS_NORMAL;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* There may be a delay between the node being promoted
|
|
* and the local record being updated, so if the node
|
|
* record still shows it as a standby, do nothing, we'll
|
|
* catch the update during the next loop. (e.g. node was
|
|
* manually promoted) we'll do nothing, as the repmgr
|
|
* metadata is now out-of-sync. If it does get fixed,
|
|
* we'll catch it here on a future iteration.
|
|
*/
|
|
|
|
/* refresh own internal node record */
|
|
record_status = get_node_record(local_conn, local_node_info.node_id, &local_node_info);
|
|
|
|
if (local_node_info.type == PRIMARY)
|
|
{
|
|
int degraded_monitoring_elapsed = calculate_elapsed(degraded_monitoring_start);
|
|
|
|
log_notice(_("resuming monitoring as primary node after %i seconds"),
|
|
degraded_monitoring_elapsed);
|
|
|
|
/* this will restart monitoring in primary mode */
|
|
monitoring_state = MS_NORMAL;
|
|
return;
|
|
}
|
|
}
|
|
|
|
|
|
if (config_file_options.failover == FAILOVER_AUTOMATIC)
|
|
{
|
|
get_active_sibling_node_records(local_conn,
|
|
local_node_info.node_id,
|
|
local_node_info.upstream_node_id,
|
|
&sibling_nodes);
|
|
|
|
if (sibling_nodes.node_count > 0)
|
|
{
|
|
log_debug("scanning %i node records to detect new primary...", sibling_nodes.node_count);
|
|
for (cell = sibling_nodes.head; cell; cell = cell->next)
|
|
{
|
|
/* skip local node check, we did that above */
|
|
if (cell->node_info->node_id == local_node_info.node_id)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
cell->node_info->conn = establish_db_connection(cell->node_info->conninfo, false);
|
|
|
|
if (PQstatus(cell->node_info->conn) != CONNECTION_OK)
|
|
{
|
|
log_debug("unable to connect to %i ... ", cell->node_info->node_id);
|
|
continue;
|
|
}
|
|
|
|
if (get_recovery_type(cell->node_info->conn) == RECTYPE_PRIMARY)
|
|
{
|
|
follow_node_id = cell->node_info->node_id;
|
|
close_connection(&cell->node_info->conn);
|
|
break;
|
|
}
|
|
close_connection(&cell->node_info->conn);
|
|
}
|
|
|
|
if (follow_node_id != UNKNOWN_NODE_ID)
|
|
{
|
|
follow_new_primary(follow_node_id);
|
|
}
|
|
}
|
|
clear_node_info_list(&sibling_nodes);
|
|
}
|
|
}
|
|
}
|
|
|
|
loop:
|
|
|
|
/* emit "still alive" log message at regular intervals, if requested */
|
|
if (config_file_options.log_status_interval > 0)
|
|
{
|
|
int log_status_interval_elapsed = calculate_elapsed(log_status_interval_start);
|
|
|
|
if (log_status_interval_elapsed >= config_file_options.log_status_interval)
|
|
{
|
|
PQExpBufferData monitoring_summary;
|
|
|
|
initPQExpBuffer(&monitoring_summary);
|
|
|
|
appendPQExpBuffer(&monitoring_summary,
|
|
_("node \"%s\" (node ID: %i) monitoring upstream node \"%s\" (node ID: %i) in %s state"),
|
|
local_node_info.node_name,
|
|
local_node_info.node_id,
|
|
upstream_node_info.node_name,
|
|
upstream_node_info.node_id,
|
|
print_monitoring_state(monitoring_state));
|
|
|
|
if (config_file_options.failover == FAILOVER_MANUAL)
|
|
{
|
|
appendPQExpBuffer(
|
|
&monitoring_summary,
|
|
_(" (automatic failover disabled)"));
|
|
}
|
|
|
|
log_info("%s", monitoring_summary.data);
|
|
termPQExpBuffer(&monitoring_summary);
|
|
if (monitoring_state == MS_DEGRADED && config_file_options.failover == FAILOVER_AUTOMATIC)
|
|
{
|
|
log_detail(_("waiting for upstream or another primary to reappear"));
|
|
}
|
|
|
|
INSTR_TIME_SET_CURRENT(log_status_interval_start);
|
|
}
|
|
}
|
|
|
|
if (PQstatus(primary_conn) == CONNECTION_OK && config_file_options.monitoring_history == true)
|
|
{
|
|
update_monitoring_history();
|
|
}
|
|
else
|
|
{
|
|
connection_ping(local_conn);
|
|
}
|
|
|
|
/*
|
|
* handle local node failure
|
|
*
|
|
* currently we'll just check the connection, and try to reconnect
|
|
*
|
|
* TODO: add timeout, after which we run in degraded state
|
|
*/
|
|
|
|
check_connection(&local_node_info, &local_conn);
|
|
|
|
if (PQstatus(local_conn) != CONNECTION_OK)
|
|
{
|
|
if (local_node_info.active == true)
|
|
{
|
|
bool success = true;
|
|
PQExpBufferData event_details;
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
local_node_info.active = false;
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("unable to connect to local node \"%s\" (ID: %i), marking inactive"),
|
|
local_node_info.node_name,
|
|
local_node_info.node_id);
|
|
log_notice("%s", event_details.data);
|
|
|
|
if (PQstatus(primary_conn) == CONNECTION_OK)
|
|
{
|
|
if (update_node_record_set_active(primary_conn, local_node_info.node_id, false) == false)
|
|
{
|
|
success = false;
|
|
log_warning(_("unable to mark node \"%s\" (ID: %i) as inactive"),
|
|
local_node_info.node_name,
|
|
local_node_info.node_id);
|
|
}
|
|
}
|
|
|
|
create_event_notification(primary_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"standby_failure",
|
|
success,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (local_node_info.active == false)
|
|
{
|
|
if (PQstatus(primary_conn) == CONNECTION_OK)
|
|
{
|
|
if (update_node_record_set_active(primary_conn, local_node_info.node_id, true) == true)
|
|
{
|
|
PQExpBufferData event_details;
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
local_node_info.active = true;
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("reconnected to local node \"%s\" (ID: %i), marking active"),
|
|
local_node_info.node_name,
|
|
local_node_info.node_id);
|
|
|
|
log_warning("%s", event_details.data)
|
|
|
|
|
|
create_event_notification(primary_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"standby_recovery",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
if (got_SIGHUP)
|
|
{
|
|
log_debug("SIGHUP received");
|
|
|
|
if (reload_config(&config_file_options))
|
|
{
|
|
close_connection(&local_conn);
|
|
local_conn = establish_db_connection(config_file_options.conninfo, true);
|
|
|
|
if (*config_file_options.log_file)
|
|
{
|
|
FILE *fd;
|
|
|
|
fd = freopen(config_file_options.log_file, "a", stderr);
|
|
if (fd == NULL)
|
|
{
|
|
fprintf(stderr, "error reopening stderr to \"%s\": %s",
|
|
config_file_options.log_file, strerror(errno));
|
|
}
|
|
}
|
|
}
|
|
got_SIGHUP = false;
|
|
}
|
|
|
|
log_verbose(LOG_DEBUG, "sleeping %i seconds (parameter \"monitor_interval_secs\")",
|
|
config_file_options.monitor_interval_secs);
|
|
|
|
sleep(config_file_options.monitor_interval_secs);
|
|
}
|
|
}
|
|
|
|
|
|
void
|
|
monitor_streaming_witness(void)
|
|
{
|
|
instr_time log_status_interval_start;
|
|
instr_time witness_sync_interval_start;
|
|
|
|
PQExpBufferData event_details;
|
|
RecordStatus record_status;
|
|
|
|
reset_node_voting_status();
|
|
|
|
log_debug("monitor_streaming_witness()");
|
|
|
|
if (get_primary_node_record(local_conn, &upstream_node_info) == false)
|
|
{
|
|
PQExpBufferData event_details;
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("unable to retrieve record for primary node"));
|
|
|
|
log_error("%s", event_details.data);
|
|
log_hint(_("execute \"repmgr witness register --force\" to update the witness node "));
|
|
close_connection(&local_conn);
|
|
|
|
create_event_notification(NULL,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_shutdown",
|
|
false,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
terminate(ERR_BAD_CONFIG);
|
|
}
|
|
|
|
primary_conn = establish_db_connection(upstream_node_info.conninfo, false);
|
|
|
|
/*
|
|
* Primary node must be running at repmgrd startup.
|
|
*
|
|
* We could possibly have repmgrd skip to degraded monitoring mode until
|
|
* it comes up, but there doesn't seem to be much point in doing that.
|
|
*/
|
|
if (PQstatus(primary_conn) != CONNECTION_OK)
|
|
{
|
|
log_error(_("unable connect to upstream node (ID: %i), terminating"),
|
|
upstream_node_info.node_id);
|
|
log_hint(_("primary node must be running before repmgrd can start"));
|
|
|
|
close_connection(&local_conn);
|
|
exit(ERR_DB_CONN);
|
|
}
|
|
|
|
/* synchronise local copy of "repmgr.nodes", in case it was stale */
|
|
witness_copy_node_records(primary_conn, local_conn);
|
|
|
|
/*
|
|
* refresh upstream node record from primary, so it's as up-to-date
|
|
* as possible
|
|
*/
|
|
record_status = get_node_record(primary_conn, upstream_node_info.node_id, &upstream_node_info);
|
|
|
|
/*
|
|
* This is unlikely to happen; if it does emit a warning for diagnostic
|
|
* purposes and plough on regardless.
|
|
*
|
|
* A check for the existence of the record will have already been carried out
|
|
* in main().
|
|
*/
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_warning(_("unable to retrieve node record from primary"));
|
|
}
|
|
|
|
|
|
/* Log startup event */
|
|
if (startup_event_logged == false)
|
|
{
|
|
PQExpBufferData event_details;
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("witness monitoring connection to primary node \"%s\" (node ID: %i)"),
|
|
upstream_node_info.node_name,
|
|
upstream_node_info.node_id);
|
|
|
|
create_event_notification(primary_conn,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_start",
|
|
true,
|
|
event_details.data);
|
|
|
|
startup_event_logged = true;
|
|
|
|
log_info("%s", event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
}
|
|
|
|
monitoring_state = MS_NORMAL;
|
|
INSTR_TIME_SET_CURRENT(log_status_interval_start);
|
|
INSTR_TIME_SET_CURRENT(witness_sync_interval_start);
|
|
|
|
upstream_node_info.node_status = NODE_STATUS_UP;
|
|
|
|
while (true)
|
|
{
|
|
if (is_server_available(upstream_node_info.conninfo) == false)
|
|
{
|
|
if (upstream_node_info.node_status == NODE_STATUS_UP)
|
|
{
|
|
instr_time upstream_node_unreachable_start;
|
|
|
|
INSTR_TIME_SET_CURRENT(upstream_node_unreachable_start);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
upstream_node_info.node_status = NODE_STATUS_UNKNOWN;
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("unable to connect to primary node \"%s\" (node ID: %i)"),
|
|
upstream_node_info.node_name, upstream_node_info.node_id);
|
|
|
|
create_event_record(NULL,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_upstream_disconnect",
|
|
true,
|
|
event_details.data);
|
|
|
|
close_connection(&primary_conn);
|
|
primary_conn = try_reconnect(&upstream_node_info);
|
|
|
|
/* Node has recovered - log and continue */
|
|
if (upstream_node_info.node_status == NODE_STATUS_UP)
|
|
{
|
|
int upstream_node_unreachable_elapsed = calculate_elapsed(upstream_node_unreachable_start);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("reconnected to upstream node after %i seconds"),
|
|
upstream_node_unreachable_elapsed);
|
|
log_notice("%s", event_details.data);
|
|
|
|
create_event_notification(upstream_conn,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_upstream_reconnect",
|
|
true,
|
|
event_details.data);
|
|
termPQExpBuffer(&event_details);
|
|
|
|
goto loop;
|
|
}
|
|
|
|
/* still down after reconnect attempt(s) */
|
|
if (upstream_node_info.node_status == NODE_STATUS_DOWN)
|
|
{
|
|
bool failover_done = false;
|
|
|
|
|
|
failover_done = do_witness_failover();
|
|
|
|
/*
|
|
* XXX it's possible it will make sense to return in all
|
|
* cases to restart monitoring
|
|
*/
|
|
if (failover_done == true)
|
|
{
|
|
primary_node_id = get_primary_node_id(local_conn);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
if (monitoring_state == MS_DEGRADED)
|
|
{
|
|
int degraded_monitoring_elapsed = calculate_elapsed(degraded_monitoring_start);
|
|
|
|
log_debug("monitoring node %i in degraded state for %i seconds",
|
|
upstream_node_info.node_id,
|
|
degraded_monitoring_elapsed);
|
|
|
|
if (is_server_available(upstream_node_info.conninfo) == true)
|
|
{
|
|
primary_conn = establish_db_connection(upstream_node_info.conninfo, false);
|
|
|
|
if (PQstatus(primary_conn) == CONNECTION_OK)
|
|
{
|
|
upstream_node_info.node_status = NODE_STATUS_UP;
|
|
monitoring_state = MS_NORMAL;
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("reconnected to upstream node %i after %i seconds, resuming monitoring"),
|
|
upstream_node_info.node_id,
|
|
degraded_monitoring_elapsed);
|
|
|
|
create_event_notification(primary_conn,
|
|
&config_file_options,
|
|
config_file_options.node_id,
|
|
"repmgrd_upstream_reconnect",
|
|
true,
|
|
event_details.data);
|
|
|
|
log_notice("%s", event_details.data);
|
|
termPQExpBuffer(&event_details);
|
|
|
|
goto loop;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* unable to connect to former primary - check if another node
|
|
* has been promoted
|
|
*/
|
|
|
|
NodeInfoListCell *cell;
|
|
int follow_node_id = UNKNOWN_NODE_ID;
|
|
|
|
get_active_sibling_node_records(local_conn,
|
|
local_node_info.node_id,
|
|
local_node_info.upstream_node_id,
|
|
&sibling_nodes);
|
|
|
|
if (sibling_nodes.node_count > 0)
|
|
{
|
|
log_debug("scanning %i node records to detect new primary...", sibling_nodes.node_count);
|
|
for (cell = sibling_nodes.head; cell; cell = cell->next)
|
|
{
|
|
/* skip local node check, we did that above */
|
|
if (cell->node_info->node_id == local_node_info.node_id)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
cell->node_info->conn = establish_db_connection(cell->node_info->conninfo, false);
|
|
|
|
if (PQstatus(cell->node_info->conn) != CONNECTION_OK)
|
|
{
|
|
log_debug("unable to connect to %i ... ", cell->node_info->node_id);
|
|
continue;
|
|
}
|
|
|
|
if (get_recovery_type(cell->node_info->conn) == RECTYPE_PRIMARY)
|
|
{
|
|
follow_node_id = cell->node_info->node_id;
|
|
close_connection(&cell->node_info->conn);
|
|
break;
|
|
}
|
|
close_connection(&cell->node_info->conn);
|
|
}
|
|
|
|
if (follow_node_id != UNKNOWN_NODE_ID)
|
|
{
|
|
witness_follow_new_primary(follow_node_id);
|
|
}
|
|
}
|
|
clear_node_info_list(&sibling_nodes);
|
|
}
|
|
}
|
|
loop:
|
|
|
|
/* refresh repmgr.nodes after "witness_sync_interval" seconds */
|
|
|
|
{
|
|
int witness_sync_interval_elapsed = calculate_elapsed(witness_sync_interval_start);
|
|
if (witness_sync_interval_elapsed >= config_file_options.witness_sync_interval)
|
|
{
|
|
log_debug("synchronising witness node records");
|
|
witness_copy_node_records(primary_conn, local_conn);
|
|
INSTR_TIME_SET_CURRENT(witness_sync_interval_start);
|
|
}
|
|
}
|
|
|
|
/* emit "still alive" log message at regular intervals, if requested */
|
|
if (config_file_options.log_status_interval > 0)
|
|
{
|
|
int log_status_interval_elapsed = calculate_elapsed(log_status_interval_start);
|
|
|
|
if (log_status_interval_elapsed >= config_file_options.log_status_interval)
|
|
{
|
|
PQExpBufferData monitoring_summary;
|
|
|
|
initPQExpBuffer(&monitoring_summary);
|
|
|
|
appendPQExpBuffer(&monitoring_summary,
|
|
_("witness node \"%s\" (node ID: %i) monitoring primary node \"%s\" (node ID: %i) in %s state"),
|
|
local_node_info.node_name,
|
|
local_node_info.node_id,
|
|
upstream_node_info.node_name,
|
|
upstream_node_info.node_id,
|
|
print_monitoring_state(monitoring_state));
|
|
|
|
log_info("%s", monitoring_summary.data);
|
|
termPQExpBuffer(&monitoring_summary);
|
|
if (monitoring_state == MS_DEGRADED && config_file_options.failover == FAILOVER_AUTOMATIC)
|
|
{
|
|
log_detail(_("waiting for current or new primary to reappear"));
|
|
}
|
|
|
|
INSTR_TIME_SET_CURRENT(log_status_interval_start);
|
|
}
|
|
}
|
|
|
|
|
|
if (got_SIGHUP)
|
|
{
|
|
log_debug("SIGHUP received");
|
|
|
|
if (reload_config(&config_file_options))
|
|
{
|
|
close_connection(&local_conn);
|
|
local_conn = establish_db_connection(config_file_options.conninfo, true);
|
|
|
|
if (*config_file_options.log_file)
|
|
{
|
|
FILE *fd;
|
|
|
|
fd = freopen(config_file_options.log_file, "a", stderr);
|
|
if (fd == NULL)
|
|
{
|
|
fprintf(stderr, "error reopening stderr to \"%s\": %s",
|
|
config_file_options.log_file, strerror(errno));
|
|
}
|
|
}
|
|
}
|
|
got_SIGHUP = false;
|
|
}
|
|
|
|
log_verbose(LOG_DEBUG, "sleeping %i seconds (parameter \"monitor_interval_secs\")",
|
|
config_file_options.monitor_interval_secs);
|
|
|
|
sleep(config_file_options.monitor_interval_secs);
|
|
}
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
static bool
|
|
do_primary_failover(void)
|
|
{
|
|
ElectionResult election_result;
|
|
|
|
/*
|
|
* Double-check status of the local connection
|
|
*/
|
|
check_connection(&local_node_info, &local_conn);
|
|
|
|
/* attempt to initiate voting process */
|
|
election_result = do_election();
|
|
|
|
/* TODO add pre-event notification here */
|
|
failover_state = FAILOVER_STATE_UNKNOWN;
|
|
|
|
log_debug("election result: %s", _print_election_result(election_result));
|
|
|
|
if (election_result == ELECTION_CANCELLED)
|
|
{
|
|
log_notice(_("election cancelled"));
|
|
return false;
|
|
}
|
|
else if (election_result == ELECTION_WON)
|
|
{
|
|
if (sibling_nodes.node_count > 0)
|
|
{
|
|
log_notice("this node is the winner, will now promote itself and inform other nodes");
|
|
}
|
|
else
|
|
{
|
|
log_notice("this node is the only available candidate and will now promote itself");
|
|
}
|
|
|
|
failover_state = promote_self();
|
|
}
|
|
else if (election_result == ELECTION_LOST || election_result == ELECTION_NOT_CANDIDATE)
|
|
{
|
|
log_info(_("follower node awaiting notification from the candidate node"));
|
|
failover_state = FAILOVER_STATE_WAITING_NEW_PRIMARY;
|
|
}
|
|
|
|
/*
|
|
* node has decided it is a follower, so will await notification from the
|
|
* candidate that it has promoted itself and can be followed
|
|
*/
|
|
if (failover_state == FAILOVER_STATE_WAITING_NEW_PRIMARY)
|
|
{
|
|
int new_primary_id = UNKNOWN_NODE_ID;
|
|
|
|
/* TODO: rerun election if new primary doesn't appear after timeout */
|
|
|
|
/* either follow, self-promote or time out; either way resume monitoring */
|
|
if (wait_primary_notification(&new_primary_id) == true)
|
|
{
|
|
/* if primary has reappeared, no action needed */
|
|
if (new_primary_id == upstream_node_info.node_id)
|
|
{
|
|
failover_state = FAILOVER_STATE_FOLLOWING_ORIGINAL_PRIMARY;
|
|
}
|
|
/* if new_primary_id is self, promote */
|
|
else if (new_primary_id == local_node_info.node_id)
|
|
{
|
|
log_notice(_("this node is promotion candidate, promoting"));
|
|
|
|
failover_state = promote_self();
|
|
|
|
get_active_sibling_node_records(local_conn,
|
|
local_node_info.node_id,
|
|
upstream_node_info.node_id,
|
|
&sibling_nodes);
|
|
|
|
}
|
|
else if (config_file_options.failover == FAILOVER_MANUAL)
|
|
{
|
|
/* automatic failover disabled */
|
|
|
|
t_node_info new_primary = T_NODE_INFO_INITIALIZER;
|
|
RecordStatus record_status = RECORD_NOT_FOUND;
|
|
PGconn *new_primary_conn;
|
|
|
|
record_status = get_node_record(local_conn, new_primary_id, &new_primary);
|
|
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record for new primary node (ID: %i)"),
|
|
new_primary_id);
|
|
}
|
|
else
|
|
{
|
|
PQExpBufferData event_details;
|
|
|
|
initPQExpBuffer(&event_details);
|
|
appendPQExpBuffer(&event_details,
|
|
_("node %i is in manual failover mode and is now disconnected from streaming replication"),
|
|
local_node_info.node_id);
|
|
|
|
new_primary_conn = establish_db_connection(new_primary.conninfo, false);
|
|
|
|
create_event_notification(new_primary_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"standby_disconnect_manual",
|
|
/*
|
|
* here "true" indicates the action has occurred as expected
|
|
*/
|
|
true,
|
|
event_details.data);
|
|
close_connection(&new_primary_conn);
|
|
termPQExpBuffer(&event_details);
|
|
|
|
}
|
|
failover_state = FAILOVER_STATE_REQUIRES_MANUAL_FAILOVER;
|
|
}
|
|
else
|
|
{
|
|
failover_state = follow_new_primary(new_primary_id);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
failover_state = FAILOVER_STATE_NO_NEW_PRIMARY;
|
|
}
|
|
}
|
|
|
|
log_verbose(LOG_DEBUG, "failover state is %s",
|
|
format_failover_state(failover_state));
|
|
|
|
switch (failover_state)
|
|
{
|
|
case FAILOVER_STATE_PROMOTED:
|
|
/* notify former siblings that they should now follow this node */
|
|
notify_followers(&sibling_nodes, local_node_info.node_id);
|
|
|
|
/* we no longer care about our former siblings */
|
|
clear_node_info_list(&sibling_nodes);
|
|
|
|
/* pass control back down to start_monitoring() */
|
|
log_info(_("switching to primary monitoring mode"));
|
|
|
|
failover_state = FAILOVER_STATE_NONE;
|
|
return true;
|
|
|
|
case FAILOVER_STATE_PRIMARY_REAPPEARED:
|
|
|
|
/*
|
|
* notify siblings that they should resume following the original
|
|
* primary
|
|
*/
|
|
notify_followers(&sibling_nodes, upstream_node_info.node_id);
|
|
|
|
/* we no longer care about our former siblings */
|
|
clear_node_info_list(&sibling_nodes);
|
|
|
|
/* pass control back down to start_monitoring() */
|
|
log_info(_("resuming standby monitoring mode"));
|
|
log_detail(_("original primary \"%s\" (node ID: %i) reappeared"),
|
|
upstream_node_info.node_name, upstream_node_info.node_id);
|
|
|
|
failover_state = FAILOVER_STATE_NONE;
|
|
return true;
|
|
|
|
|
|
case FAILOVER_STATE_FOLLOWED_NEW_PRIMARY:
|
|
log_info(_("resuming standby monitoring mode"));
|
|
log_detail(_("following new primary \"%s\" (node id: %i)"),
|
|
upstream_node_info.node_name, upstream_node_info.node_id);
|
|
failover_state = FAILOVER_STATE_NONE;
|
|
|
|
return true;
|
|
|
|
case FAILOVER_STATE_FOLLOWING_ORIGINAL_PRIMARY:
|
|
log_info(_("resuming standby monitoring mode"));
|
|
log_detail(_("following original primary \"%s\" (node id: %i)"),
|
|
upstream_node_info.node_name, upstream_node_info.node_id);
|
|
failover_state = FAILOVER_STATE_NONE;
|
|
|
|
return true;
|
|
|
|
case FAILOVER_STATE_PROMOTION_FAILED:
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
|
|
return false;
|
|
|
|
case FAILOVER_STATE_FOLLOW_FAIL:
|
|
|
|
/*
|
|
* for whatever reason we were unable to follow the new primary -
|
|
* continue monitoring in degraded state
|
|
*/
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
|
|
return false;
|
|
|
|
case FAILOVER_STATE_REQUIRES_MANUAL_FAILOVER:
|
|
log_info(_("automatic failover disabled for this node, manual intervention required"));
|
|
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
return false;
|
|
|
|
case FAILOVER_STATE_NO_NEW_PRIMARY:
|
|
case FAILOVER_STATE_WAITING_NEW_PRIMARY:
|
|
/* pass control back down to start_monitoring() */
|
|
return false;
|
|
|
|
case FAILOVER_STATE_NODE_NOTIFICATION_ERROR:
|
|
case FAILOVER_STATE_LOCAL_NODE_FAILURE:
|
|
case FAILOVER_STATE_UNKNOWN:
|
|
case FAILOVER_STATE_NONE:
|
|
return false;
|
|
}
|
|
|
|
/* should never reach here */
|
|
return false;
|
|
}
|
|
|
|
|
|
|
|
|
|
static void
|
|
update_monitoring_history(void)
|
|
{
|
|
ReplInfo replication_info = T_REPLINFO_INTIALIZER;
|
|
XLogRecPtr primary_last_wal_location = InvalidXLogRecPtr;
|
|
|
|
long long unsigned int apply_lag_bytes = 0;
|
|
long long unsigned int replication_lag_bytes = 0;
|
|
|
|
/* both local and primary connections must be available */
|
|
if (PQstatus(primary_conn) != CONNECTION_OK || PQstatus(local_conn) != CONNECTION_OK)
|
|
return;
|
|
|
|
if (get_replication_info(local_conn, &replication_info) == false)
|
|
{
|
|
log_warning(_("unable to retrieve replication status information"));
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* This can be the case when a standby is starting up after following
|
|
* a new primary, or when it has dropped back to archive recovery.
|
|
* As long as we can connect to the primary, we can still provide lag information.
|
|
*/
|
|
if (replication_info.receiving_streamed_wal == false)
|
|
{
|
|
log_verbose(LOG_WARNING, _("standby %i not connected to streaming replication"),
|
|
local_node_info.node_id);
|
|
}
|
|
|
|
primary_last_wal_location = get_current_wal_lsn(primary_conn);
|
|
|
|
if (primary_last_wal_location == InvalidXLogRecPtr)
|
|
{
|
|
log_warning(_("unable to retrieve primary's current LSN"));
|
|
return;
|
|
}
|
|
|
|
/* calculate apply lag in bytes */
|
|
if (replication_info.last_wal_receive_lsn >= replication_info.last_wal_replay_lsn)
|
|
{
|
|
apply_lag_bytes = (long long unsigned int) (replication_info.last_wal_receive_lsn - replication_info.last_wal_replay_lsn);
|
|
}
|
|
else
|
|
{
|
|
/* if this happens, it probably indicates archive recovery */
|
|
apply_lag_bytes = 0;
|
|
}
|
|
|
|
/* calculate replication lag in bytes */
|
|
|
|
if (primary_last_wal_location >= replication_info.last_wal_receive_lsn)
|
|
{
|
|
replication_lag_bytes = (long long unsigned int) (primary_last_wal_location - replication_info.last_wal_receive_lsn);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* This should never happen, but in case it does set replication lag
|
|
* to zero
|
|
*/
|
|
log_warning("primary xlog (%X/%X) location appears less than standby receive location (%X/%X)",
|
|
format_lsn(primary_last_wal_location),
|
|
format_lsn(replication_info.last_wal_receive_lsn));
|
|
replication_lag_bytes = 0;
|
|
}
|
|
|
|
add_monitoring_record(
|
|
primary_conn,
|
|
local_conn,
|
|
primary_node_id,
|
|
local_node_info.node_id,
|
|
replication_info.current_timestamp,
|
|
primary_last_wal_location,
|
|
replication_info.last_wal_receive_lsn,
|
|
replication_info.last_xact_replay_timestamp,
|
|
replication_lag_bytes,
|
|
apply_lag_bytes);
|
|
}
|
|
|
|
|
|
/*
|
|
* do_upstream_standby_failover()
|
|
*
|
|
* Attach cascaded standby to primary
|
|
*
|
|
* Currently we will try to attach to the cluster primary, as "repmgr
|
|
* standby follow" doesn't support attaching to another node.
|
|
*
|
|
* If this becomes supported, it might be worth providing a selection
|
|
* of reconnection strategies as different behaviour might be desirable
|
|
* in different situations;
|
|
* or maybe the option not to reconnect might be required?
|
|
*/
|
|
|
|
static bool
|
|
do_upstream_standby_failover(void)
|
|
{
|
|
PQExpBufferData event_details;
|
|
t_node_info primary_node_info = T_NODE_INFO_INITIALIZER;
|
|
RecordStatus record_status = RECORD_NOT_FOUND;
|
|
RecoveryType primary_type = RECTYPE_UNKNOWN;
|
|
int i, r;
|
|
char parsed_follow_command[MAXPGPATH] = "";
|
|
|
|
close_connection(&upstream_conn);
|
|
|
|
if (get_primary_node_record(local_conn, &primary_node_info) == false)
|
|
{
|
|
log_error(_("unable to retrieve primary node record"));
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Verify that we can still talk to the cluster primary, even though the
|
|
* node's upstream is not available
|
|
*/
|
|
|
|
check_connection(&primary_node_info, &primary_conn);
|
|
|
|
if (PQstatus(primary_conn) != CONNECTION_OK)
|
|
{
|
|
log_error(_("unable to connect to last known primary \"%s\" (ID: %i)"),
|
|
primary_node_info.node_name,
|
|
primary_node_info.node_id);
|
|
|
|
close_connection(&primary_conn);
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
return false;
|
|
}
|
|
|
|
primary_type = get_recovery_type(primary_conn);
|
|
|
|
if (primary_type != RECTYPE_PRIMARY)
|
|
{
|
|
log_error(_("last known primary\"%s\" (ID: %i) is in recovery, not following"),
|
|
primary_node_info.node_name,
|
|
primary_node_info.node_id);
|
|
|
|
close_connection(&primary_conn);
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
return false;
|
|
}
|
|
|
|
/* Close the connection to this server */
|
|
close_connection(&local_conn);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
log_debug(_("standby follow command is:\n \"%s\""),
|
|
config_file_options.follow_command);
|
|
|
|
/*
|
|
* replace %n in "config_file_options.follow_command" with ID of primary
|
|
* to follow.
|
|
*/
|
|
parse_follow_command(parsed_follow_command, config_file_options.follow_command, primary_node_info.node_id);
|
|
|
|
r = system(parsed_follow_command);
|
|
|
|
if (r != 0)
|
|
{
|
|
appendPQExpBuffer(&event_details,
|
|
_("unable to execute follow command:\n %s"),
|
|
config_file_options.follow_command);
|
|
|
|
log_error("%s", event_details.data);
|
|
|
|
/*
|
|
* It may not possible to write to the event notification table but we
|
|
* should be able to generate an external notification if required.
|
|
*/
|
|
create_event_notification(
|
|
primary_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_follow",
|
|
false,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
}
|
|
|
|
/*
|
|
* It's possible that the standby is still starting up after the "follow_command"
|
|
* completes, so poll for a while until we get a connection.
|
|
*/
|
|
|
|
for (i = 0; i < config_file_options.repmgrd_standby_startup_timeout; i++)
|
|
{
|
|
local_conn = establish_db_connection(local_node_info.conninfo, false);
|
|
|
|
if (PQstatus(local_conn) == CONNECTION_OK)
|
|
break;
|
|
|
|
log_debug("sleeping 1 second; %i of %i attempts to reconnect to local node",
|
|
i + 1,
|
|
config_file_options.repmgrd_standby_startup_timeout);
|
|
sleep(1);
|
|
}
|
|
|
|
if (PQstatus(local_conn) != CONNECTION_OK)
|
|
{
|
|
log_error(_("unable to reconnect to local node %i"),
|
|
local_node_info.node_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
/* refresh shared memory settings which will have been zapped by the restart */
|
|
repmgrd_set_local_node_id(local_conn, config_file_options.node_id);
|
|
|
|
if (update_node_record_set_upstream(primary_conn,
|
|
local_node_info.node_id,
|
|
primary_node_info.node_id) == false)
|
|
{
|
|
appendPQExpBuffer(&event_details,
|
|
_("unable to set node %i's new upstream ID to %i"),
|
|
local_node_info.node_id,
|
|
primary_node_info.node_id);
|
|
|
|
log_error("%s", event_details.data);
|
|
|
|
create_event_notification(
|
|
NULL,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_follow",
|
|
false,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
terminate(ERR_BAD_CONFIG);
|
|
}
|
|
|
|
/* refresh own internal node record */
|
|
record_status = get_node_record(primary_conn, local_node_info.node_id, &local_node_info);
|
|
|
|
/*
|
|
* highly improbable this will happen, but in case we're unable to
|
|
* retrieve our node record from the primary, update it ourselves, and
|
|
* hope for the best
|
|
*/
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
local_node_info.upstream_node_id = primary_node_info.node_id;
|
|
}
|
|
|
|
appendPQExpBuffer(&event_details,
|
|
_("node %i is now following primary node %i"),
|
|
local_node_info.node_id,
|
|
primary_node_info.node_id);
|
|
|
|
log_notice("%s", event_details.data);
|
|
|
|
create_event_notification(
|
|
primary_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_follow",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
/* keep the primary connection open */
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
static FailoverState
|
|
promote_self(void)
|
|
{
|
|
PQExpBufferData event_details;
|
|
char *promote_command;
|
|
int r;
|
|
|
|
/* Store details of the failed node here */
|
|
t_node_info failed_primary = T_NODE_INFO_INITIALIZER;
|
|
RecordStatus record_status;
|
|
|
|
/*
|
|
* optionally add a delay before promoting the standby; this is mainly
|
|
* useful for testing (e.g. for reappearance of the original primary) and
|
|
* is not documented.
|
|
*/
|
|
if (config_file_options.promote_delay > 0)
|
|
{
|
|
log_debug("sleeping %i seconds before promoting standby",
|
|
config_file_options.promote_delay);
|
|
sleep(config_file_options.promote_delay);
|
|
}
|
|
|
|
record_status = get_node_record(local_conn, local_node_info.upstream_node_id, &failed_primary);
|
|
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record for failed upstream (ID: %i)"),
|
|
local_node_info.upstream_node_id);
|
|
return FAILOVER_STATE_PROMOTION_FAILED;
|
|
}
|
|
|
|
/* the presence of this command has been established already */
|
|
promote_command = config_file_options.promote_command;
|
|
|
|
log_info(_("promote_command is:\n \"%s\""),
|
|
promote_command);
|
|
|
|
if (log_type == REPMGR_STDERR && *config_file_options.log_file)
|
|
{
|
|
fflush(stderr);
|
|
}
|
|
|
|
r = system(promote_command);
|
|
|
|
/* connection should stay up, but check just in case */
|
|
if (PQstatus(local_conn) != CONNECTION_OK)
|
|
{
|
|
local_conn = establish_db_connection(local_node_info.conninfo, true);
|
|
|
|
/* assume node failed */
|
|
if (PQstatus(local_conn) != CONNECTION_OK)
|
|
{
|
|
log_error(_("unable to reconnect to local node"));
|
|
/* XXX handle this */
|
|
return FAILOVER_STATE_LOCAL_NODE_FAILURE;
|
|
}
|
|
}
|
|
|
|
if (r != 0)
|
|
{
|
|
int primary_node_id;
|
|
|
|
upstream_conn = get_primary_connection(local_conn,
|
|
&primary_node_id, NULL);
|
|
|
|
if (PQstatus(upstream_conn) == CONNECTION_OK && primary_node_id == failed_primary.node_id)
|
|
{
|
|
log_notice(_("original primary (id: %i) reappeared before this standby was promoted - no action taken"),
|
|
failed_primary.node_id);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
appendPQExpBuffer(&event_details,
|
|
_("original primary \"%s\" (node ID: %i) reappeared"),
|
|
failed_primary.node_name,
|
|
failed_primary.node_id);
|
|
|
|
create_event_notification(upstream_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_abort",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
/* XXX handle this! */
|
|
/* -> we'll need to let the other nodes know too.... */
|
|
/* no failover occurred but we'll want to restart connections */
|
|
|
|
return FAILOVER_STATE_PRIMARY_REAPPEARED;
|
|
}
|
|
|
|
|
|
log_error(_("promote command failed"));
|
|
initPQExpBuffer(&event_details);
|
|
|
|
create_event_notification(
|
|
NULL,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_promote_error",
|
|
true,
|
|
event_details.data);
|
|
termPQExpBuffer(&event_details);
|
|
|
|
return FAILOVER_STATE_PROMOTION_FAILED;
|
|
}
|
|
|
|
/* bump the electoral term */
|
|
increment_current_term(local_conn);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
|
|
/* update own internal node record */
|
|
record_status = get_node_record(local_conn, local_node_info.node_id, &local_node_info);
|
|
|
|
/*
|
|
* XXX here we're assuming the promote command updated metadata
|
|
*/
|
|
appendPQExpBuffer(&event_details,
|
|
_("node %i promoted to primary; old primary %i marked as failed"),
|
|
local_node_info.node_id,
|
|
failed_primary.node_id);
|
|
|
|
/* local_conn is now the primary connection */
|
|
create_event_notification(local_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_promote",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
return FAILOVER_STATE_PROMOTED;
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
* Notify follower nodes about which node to follow. Normally this
|
|
* will be the current node, however if the original primary reappeared
|
|
* before this node could be promoted, we'll inform the followers they
|
|
* should resume monitoring the original primary.
|
|
*/
|
|
static void
|
|
notify_followers(NodeInfoList *standby_nodes, int follow_node_id)
|
|
{
|
|
NodeInfoListCell *cell;
|
|
|
|
log_verbose(LOG_NOTICE, "%i followers to notify",
|
|
standby_nodes->node_count);
|
|
|
|
for (cell = standby_nodes->head; cell; cell = cell->next)
|
|
{
|
|
log_verbose(LOG_DEBUG, "intending to notify node %i... ", cell->node_info->node_id);
|
|
if (PQstatus(cell->node_info->conn) != CONNECTION_OK)
|
|
{
|
|
log_debug("reconnecting to node %i... ", cell->node_info->node_id);
|
|
|
|
cell->node_info->conn = establish_db_connection(cell->node_info->conninfo, false);
|
|
}
|
|
|
|
if (PQstatus(cell->node_info->conn) != CONNECTION_OK)
|
|
{
|
|
log_debug("unable to reconnect to %i ... ", cell->node_info->node_id);
|
|
|
|
continue;
|
|
}
|
|
|
|
log_verbose(LOG_NOTICE, "notifying node %i to follow node %i",
|
|
cell->node_info->node_id, follow_node_id);
|
|
notify_follow_primary(cell->node_info->conn, follow_node_id);
|
|
}
|
|
}
|
|
|
|
|
|
static bool
|
|
wait_primary_notification(int *new_primary_id)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < config_file_options.primary_notification_timeout; i++)
|
|
{
|
|
if (get_new_primary(local_conn, new_primary_id) == true)
|
|
{
|
|
log_debug("new primary is %i; elapsed: %i seconds",
|
|
*new_primary_id, i);
|
|
return true;
|
|
}
|
|
|
|
log_verbose(LOG_DEBUG, "waiting for new primary notification, %i of max %i seconds (\"primary_notification_timeout\")",
|
|
i, config_file_options.primary_notification_timeout);
|
|
|
|
sleep(1);
|
|
}
|
|
|
|
log_warning(_("no notification received from new primary after %i seconds"),
|
|
config_file_options.primary_notification_timeout);
|
|
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
static FailoverState
|
|
follow_new_primary(int new_primary_id)
|
|
{
|
|
char parsed_follow_command[MAXPGPATH] = "";
|
|
|
|
PQExpBufferData event_details;
|
|
int i, r;
|
|
|
|
/* Store details of the failed node here */
|
|
t_node_info failed_primary = T_NODE_INFO_INITIALIZER;
|
|
t_node_info new_primary = T_NODE_INFO_INITIALIZER;
|
|
RecordStatus record_status = RECORD_NOT_FOUND;
|
|
bool new_primary_ok = false;
|
|
|
|
record_status = get_node_record(local_conn, new_primary_id, &new_primary);
|
|
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record for new primary node (ID: %i)"),
|
|
new_primary_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
record_status = get_node_record(local_conn, local_node_info.upstream_node_id, &failed_primary);
|
|
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record for failed primary (ID: %i)"),
|
|
local_node_info.upstream_node_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
/* XXX check if new_primary_id == failed_primary.node_id? */
|
|
|
|
if (log_type == REPMGR_STDERR && *config_file_options.log_file)
|
|
{
|
|
fflush(stderr);
|
|
}
|
|
|
|
upstream_conn = establish_db_connection(new_primary.conninfo, false);
|
|
|
|
if (PQstatus(upstream_conn) == CONNECTION_OK)
|
|
{
|
|
RecoveryType primary_recovery_type = get_recovery_type(upstream_conn);
|
|
|
|
if (primary_recovery_type == RECTYPE_PRIMARY)
|
|
{
|
|
new_primary_ok = true;
|
|
}
|
|
else
|
|
{
|
|
new_primary_ok = false;
|
|
log_warning(_("new primary is not in recovery"));
|
|
close_connection(&upstream_conn);
|
|
}
|
|
}
|
|
|
|
if (new_primary_ok == false)
|
|
{
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
/*
|
|
* disconnect from local node, as follow operation will result in a server
|
|
* restart
|
|
*/
|
|
|
|
close_connection(&local_conn);
|
|
|
|
/*
|
|
* replace %n in "config_file_options.follow_command" with ID of primary
|
|
* to follow.
|
|
*/
|
|
parse_follow_command(parsed_follow_command, config_file_options.follow_command, new_primary_id);
|
|
|
|
log_debug(_("standby follow command is:\n \"%s\""),
|
|
parsed_follow_command);
|
|
|
|
/* execute the follow command */
|
|
r = system(parsed_follow_command);
|
|
|
|
if (r != 0)
|
|
{
|
|
PGconn *old_primary_conn;
|
|
|
|
/*
|
|
* The "standby follow" command could still fail due to the original primary
|
|
* reappearing before the candidate could promote itself ("repmgr
|
|
* standby follow" will refuse to promote another node if the primary
|
|
* is available). However the new primary will only instruct the other
|
|
* nodes to follow it after it's successfully promoted itself, so this
|
|
* case is highly unlikely. A slightly more likely scenario would
|
|
* be the new primary becoming unavailable just after it's sent notifications
|
|
* to its follower nodes, and the old primary becoming available again.
|
|
*/
|
|
old_primary_conn = establish_db_connection(failed_primary.conninfo, false);
|
|
|
|
if (PQstatus(old_primary_conn) == CONNECTION_OK)
|
|
{
|
|
RecoveryType upstream_recovery_type = get_recovery_type(old_primary_conn);
|
|
|
|
if (upstream_recovery_type == RECTYPE_PRIMARY)
|
|
{
|
|
initPQExpBuffer(&event_details);
|
|
appendPQExpBuffer(&event_details,
|
|
_("original primary reappeared - no action taken"));
|
|
|
|
log_notice("%s", event_details.data);
|
|
|
|
create_event_notification(old_primary_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_aborted",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
close_connection(&old_primary_conn);
|
|
|
|
return FAILOVER_STATE_PRIMARY_REAPPEARED;
|
|
}
|
|
|
|
log_notice(_("original primary reappeared as standby"));
|
|
|
|
close_connection(&old_primary_conn);
|
|
}
|
|
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
/*
|
|
* refresh local copy of local and primary node records - we get these
|
|
* directly from the primary to ensure they're the current version
|
|
*/
|
|
|
|
record_status = get_node_record(upstream_conn, new_primary_id, &upstream_node_info);
|
|
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record found for node %i"),
|
|
new_primary_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
record_status = get_node_record(upstream_conn, local_node_info.node_id, &local_node_info);
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record found for node %i"),
|
|
local_node_info.node_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
/*
|
|
* It's possible that the standby is still starting up after the "follow_command"
|
|
* completes, so poll for a while until we get a connection.
|
|
*/
|
|
|
|
for (i = 0; i < config_file_options.repmgrd_standby_startup_timeout; i++)
|
|
{
|
|
local_conn = establish_db_connection(local_node_info.conninfo, false);
|
|
|
|
if (PQstatus(local_conn) == CONNECTION_OK)
|
|
break;
|
|
|
|
log_debug("sleeping 1 second; %i of %i attempts to reconnect to local node",
|
|
i + 1,
|
|
config_file_options.repmgrd_standby_startup_timeout);
|
|
sleep(1);
|
|
}
|
|
|
|
if (PQstatus(local_conn) != CONNECTION_OK)
|
|
{
|
|
log_error(_("unable to reconnect to local node %i"),
|
|
local_node_info.node_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
/* refresh shared memory settings which will have been zapped by the restart */
|
|
repmgrd_set_local_node_id(local_conn, config_file_options.node_id);
|
|
|
|
initPQExpBuffer(&event_details);
|
|
appendPQExpBuffer(&event_details,
|
|
_("node %i now following new upstream node %i"),
|
|
local_node_info.node_id,
|
|
upstream_node_info.node_id);
|
|
|
|
log_notice("%s", event_details.data);
|
|
|
|
create_event_notification(upstream_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_follow",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
return FAILOVER_STATE_FOLLOWED_NEW_PRIMARY;
|
|
}
|
|
|
|
|
|
static FailoverState
|
|
witness_follow_new_primary(int new_primary_id)
|
|
{
|
|
PQExpBufferData event_details;
|
|
|
|
t_node_info new_primary = T_NODE_INFO_INITIALIZER;
|
|
RecordStatus record_status = RECORD_NOT_FOUND;
|
|
bool new_primary_ok = false;
|
|
|
|
record_status = get_node_record(local_conn, new_primary_id, &new_primary);
|
|
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record for new primary node (ID: %i)"),
|
|
new_primary_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
/* TODO: check if new_primary_id == failed_primary.node_id? */
|
|
|
|
if (log_type == REPMGR_STDERR && *config_file_options.log_file)
|
|
{
|
|
fflush(stderr);
|
|
}
|
|
|
|
upstream_conn = establish_db_connection(new_primary.conninfo, false);
|
|
|
|
if (PQstatus(upstream_conn) == CONNECTION_OK)
|
|
{
|
|
RecoveryType primary_recovery_type = get_recovery_type(upstream_conn);
|
|
|
|
if (primary_recovery_type == RECTYPE_PRIMARY)
|
|
{
|
|
new_primary_ok = true;
|
|
}
|
|
else
|
|
{
|
|
new_primary_ok = false;
|
|
log_warning(_("new primary is not in recovery"));
|
|
close_connection(&upstream_conn);
|
|
}
|
|
}
|
|
|
|
if (new_primary_ok == false)
|
|
{
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
/* set new upstream node ID on primary */
|
|
update_node_record_set_upstream(upstream_conn, local_node_info.node_id, new_primary_id);
|
|
|
|
witness_copy_node_records(upstream_conn, local_conn);
|
|
|
|
/*
|
|
* refresh local copy of local and primary node records - we get these
|
|
* directly from the primary to ensure they're the current version
|
|
*/
|
|
|
|
record_status = get_node_record(upstream_conn, new_primary_id, &upstream_node_info);
|
|
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record found for node %i"),
|
|
new_primary_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
record_status = get_node_record(upstream_conn, local_node_info.node_id, &local_node_info);
|
|
if (record_status != RECORD_FOUND)
|
|
{
|
|
log_error(_("unable to retrieve metadata record found for node %i"),
|
|
local_node_info.node_id);
|
|
return FAILOVER_STATE_FOLLOW_FAIL;
|
|
}
|
|
|
|
initPQExpBuffer(&event_details);
|
|
appendPQExpBuffer(&event_details,
|
|
_("witness node %i now following new primary node %i"),
|
|
local_node_info.node_id,
|
|
upstream_node_info.node_id);
|
|
|
|
log_notice("%s", event_details.data);
|
|
|
|
create_event_notification(
|
|
upstream_conn,
|
|
&config_file_options,
|
|
local_node_info.node_id,
|
|
"repmgrd_failover_follow",
|
|
true,
|
|
event_details.data);
|
|
|
|
termPQExpBuffer(&event_details);
|
|
|
|
return FAILOVER_STATE_FOLLOWED_NEW_PRIMARY;
|
|
}
|
|
|
|
|
|
static const char *
|
|
_print_election_result(ElectionResult result)
|
|
{
|
|
switch (result)
|
|
{
|
|
case ELECTION_NOT_CANDIDATE:
|
|
return "NOT CANDIDATE";
|
|
|
|
case ELECTION_WON:
|
|
return "WON";
|
|
|
|
case ELECTION_LOST:
|
|
return "LOST";
|
|
|
|
case ELECTION_CANCELLED:
|
|
return "CANCELLED";
|
|
}
|
|
|
|
/* should never reach here */
|
|
return "UNKNOWN";
|
|
}
|
|
|
|
|
|
/*
|
|
* NB: this function sets standby_nodes; caller (do_primary_failover)
|
|
* expects to be able to read this list
|
|
*/
|
|
static ElectionResult
|
|
do_election(void)
|
|
{
|
|
int electoral_term = -1;
|
|
|
|
/* we're visible */
|
|
int visible_nodes = 1;
|
|
int total_nodes = 0;
|
|
|
|
NodeInfoListCell *cell = NULL;
|
|
|
|
t_node_info *candidate_node = NULL;
|
|
|
|
/*
|
|
* Check if at least one server in the primary's location is visible; if
|
|
* not we'll assume a network split between this node and the primary
|
|
* location, and not promote any standby.
|
|
*
|
|
* NOTE: this function is only ever called by standbys attached to the
|
|
* current (unreachable) primary, so "upstream_node_info" will always
|
|
* contain the primary node record.
|
|
*/
|
|
bool primary_location_seen = false;
|
|
|
|
electoral_term = get_current_term(local_conn);
|
|
|
|
if (electoral_term == -1)
|
|
{
|
|
log_error(_("unable to determine electoral term"));
|
|
|
|
return ELECTION_NOT_CANDIDATE;
|
|
}
|
|
|
|
log_debug("do_election(): electoral term is %i", electoral_term);
|
|
|
|
|
|
if (config_file_options.failover == FAILOVER_MANUAL)
|
|
{
|
|
log_notice(_("this node is not configured for automatic failover so will not be considered as promotion candidate, and will not follow the new primary"));
|
|
log_detail(_("\"failover\" is set to \"manual\" in repmgr.conf"));
|
|
log_hint(_("manually execute \"repmgr standby follow\" to have this node follow the new primary"));
|
|
|
|
return ELECTION_NOT_CANDIDATE;
|
|
}
|
|
|
|
/* node priority is set to zero - don't become a candidate, and lose by default */
|
|
if (local_node_info.priority <= 0)
|
|
{
|
|
log_notice(_("this node's priority is %i so will not be considered as an automatic promotion candidate"),
|
|
local_node_info.priority);
|
|
|
|
return ELECTION_LOST;
|
|
}
|
|
|
|
/* get all active nodes attached to upstream, excluding self */
|
|
get_active_sibling_node_records(local_conn,
|
|
local_node_info.node_id,
|
|
upstream_node_info.node_id,
|
|
&sibling_nodes);
|
|
|
|
total_nodes = sibling_nodes.node_count + 1;
|
|
|
|
log_debug("do_election(): primary location is %s", upstream_node_info.location);
|
|
|
|
local_node_info.last_wal_receive_lsn = InvalidXLogRecPtr;
|
|
|
|
/* fast path if no other standbys (or witness) exists - normally win by default */
|
|
if (sibling_nodes.node_count == 0)
|
|
{
|
|
if (strncmp(upstream_node_info.location, local_node_info.location, MAXLEN) == 0)
|
|
{
|
|
log_debug("no other nodes - we win by default");
|
|
return ELECTION_WON;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* If primary and standby have different locations set, the assumption
|
|
* is that no action should be taken as we can't tell whether there's
|
|
* been a network interruption or not.
|
|
*
|
|
* Normally a situation with primary and standby in different physical
|
|
* locations would be handled by leaving the location as "default" and
|
|
* setting up a witness server in the primary's location.
|
|
*/
|
|
log_debug("no other nodes, but primary and standby locations differ");
|
|
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
|
|
return ELECTION_NOT_CANDIDATE;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* standby nodes found - check if we're in the primary location before checking theirs */
|
|
if (strncmp(upstream_node_info.location, local_node_info.location, MAXLEN) == 0)
|
|
{
|
|
primary_location_seen = true;
|
|
}
|
|
}
|
|
|
|
/* get our lsn */
|
|
local_node_info.last_wal_receive_lsn = get_last_wal_receive_location(local_conn);
|
|
|
|
log_debug("our last receive lsn: %X/%X", format_lsn(local_node_info.last_wal_receive_lsn));
|
|
|
|
/* pointer to "winning" node, initially self */
|
|
candidate_node = &local_node_info;
|
|
|
|
for (cell = sibling_nodes.head; cell; cell = cell->next)
|
|
{
|
|
/* assume the worst case */
|
|
cell->node_info->node_status = NODE_STATUS_UNKNOWN;
|
|
|
|
cell->node_info->conn = establish_db_connection(cell->node_info->conninfo, false);
|
|
|
|
if (PQstatus(cell->node_info->conn) != CONNECTION_OK)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
cell->node_info->node_status = NODE_STATUS_UP;
|
|
|
|
visible_nodes++;
|
|
|
|
/*
|
|
* see if the node is in the primary's location (but skip the check if
|
|
* we've seen a node there already)
|
|
*/
|
|
if (primary_location_seen == false)
|
|
{
|
|
if (strncmp(cell->node_info->location, upstream_node_info.location, MAXLEN) == 0)
|
|
{
|
|
primary_location_seen = true;
|
|
}
|
|
}
|
|
|
|
/* don't interrogate a witness server */
|
|
if (cell->node_info->type == WITNESS)
|
|
{
|
|
log_debug("node %i is witness, not querying state", cell->node_info->node_id);
|
|
continue;
|
|
}
|
|
/* XXX don't check 0-priority nodes */
|
|
|
|
/* get node's LSN - if "higher" than current winner, current node is candidate */
|
|
|
|
cell->node_info->last_wal_receive_lsn = get_last_wal_receive_location(cell->node_info->conn);
|
|
|
|
log_verbose(LOG_DEBUG, "node %i's last receive LSN is: %X/%X",
|
|
cell->node_info->node_id,
|
|
format_lsn(cell->node_info->last_wal_receive_lsn));
|
|
|
|
/* compare LSN */
|
|
if (cell->node_info->last_wal_receive_lsn > candidate_node->last_wal_receive_lsn)
|
|
{
|
|
/* other node is ahead */
|
|
log_verbose(LOG_DEBUG, "node %i is ahead of current candidate %i",
|
|
cell->node_info->node_id,
|
|
candidate_node->node_id);
|
|
|
|
candidate_node = cell->node_info;
|
|
}
|
|
/* LSN is same - tiebreak on priority, then node_id */
|
|
else if (cell->node_info->last_wal_receive_lsn == candidate_node->last_wal_receive_lsn)
|
|
{
|
|
log_verbose(LOG_DEBUG, "node %i has same LSN as current candidate %i",
|
|
cell->node_info->node_id,
|
|
candidate_node->node_id);
|
|
if (cell->node_info->priority > candidate_node->priority)
|
|
{
|
|
log_verbose(LOG_DEBUG, "node %i has higher priority (%i) than current candidate %i (%i)",
|
|
cell->node_info->node_id,
|
|
cell->node_info->priority,
|
|
candidate_node->node_id,
|
|
candidate_node->priority);
|
|
candidate_node = cell->node_info;
|
|
}
|
|
else if (cell->node_info->priority == candidate_node->priority)
|
|
{
|
|
if (cell->node_info->node_id < candidate_node->node_id)
|
|
{
|
|
log_verbose(LOG_DEBUG, "node %i has same priority but lower node_id than current candidate %i",
|
|
cell->node_info->node_id,
|
|
candidate_node->node_id);
|
|
candidate_node = cell->node_info;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
log_verbose(LOG_DEBUG, "node %i has lower priority (%i) than current candidate %i (%i)",
|
|
cell->node_info->node_id,
|
|
cell->node_info->priority,
|
|
candidate_node->node_id,
|
|
candidate_node->priority);
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
if (primary_location_seen == false)
|
|
{
|
|
log_notice(_("no nodes from the primary location \"%s\" visible - assuming network split"),
|
|
upstream_node_info.location);
|
|
log_detail(_("node will enter degraded monitoring state waiting for reconnect"));
|
|
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
|
|
reset_node_voting_status();
|
|
|
|
return ELECTION_CANCELLED;
|
|
}
|
|
|
|
log_debug("visible nodes: %i; total nodes: %i",
|
|
visible_nodes,
|
|
total_nodes);
|
|
|
|
if (visible_nodes <= (total_nodes / 2.0))
|
|
{
|
|
log_notice(_("unable to reach a qualified majority of nodes"));
|
|
log_detail(_("node will enter degraded monitoring state waiting for reconnect"));
|
|
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
|
|
reset_node_voting_status();
|
|
|
|
return ELECTION_CANCELLED;
|
|
}
|
|
|
|
log_debug("promotion candidate is %i", candidate_node->node_id);
|
|
if (candidate_node->node_id == local_node_info.node_id)
|
|
return ELECTION_WON;
|
|
|
|
return ELECTION_LOST;
|
|
}
|
|
|
|
/*
|
|
* "failover" for the witness node; the witness has no part in the election
|
|
* other than being reachable, so just needs to await notification from the
|
|
* new primary
|
|
*/
|
|
static
|
|
bool do_witness_failover(void)
|
|
{
|
|
int new_primary_id = UNKNOWN_NODE_ID;
|
|
|
|
/* TODO add pre-event notification here */
|
|
failover_state = FAILOVER_STATE_UNKNOWN;
|
|
|
|
if (wait_primary_notification(&new_primary_id) == true)
|
|
{
|
|
/* if primary has reappeared, no action needed */
|
|
if (new_primary_id == upstream_node_info.node_id)
|
|
{
|
|
failover_state = FAILOVER_STATE_FOLLOWING_ORIGINAL_PRIMARY;
|
|
}
|
|
else
|
|
{
|
|
failover_state = witness_follow_new_primary(new_primary_id);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
failover_state = FAILOVER_STATE_NO_NEW_PRIMARY;
|
|
}
|
|
|
|
|
|
log_verbose(LOG_DEBUG, "failover state is %s",
|
|
format_failover_state(failover_state));
|
|
|
|
switch (failover_state)
|
|
{
|
|
case FAILOVER_STATE_PRIMARY_REAPPEARED:
|
|
/* pass control back down to start_monitoring() */
|
|
log_info(_("resuming witness monitoring mode"));
|
|
log_detail(_("original primary \"%s\" (node ID: %i) reappeared"),
|
|
upstream_node_info.node_name, upstream_node_info.node_id);
|
|
|
|
failover_state = FAILOVER_STATE_NONE;
|
|
return true;
|
|
|
|
|
|
case FAILOVER_STATE_FOLLOWED_NEW_PRIMARY:
|
|
log_info(_("resuming standby monitoring mode"));
|
|
log_detail(_("following new primary \"%s\" (node id: %i)"),
|
|
upstream_node_info.node_name, upstream_node_info.node_id);
|
|
failover_state = FAILOVER_STATE_NONE;
|
|
|
|
return true;
|
|
|
|
case FAILOVER_STATE_FOLLOWING_ORIGINAL_PRIMARY:
|
|
log_info(_("resuming witness monitoring mode"));
|
|
log_detail(_("following original primary \"%s\" (node id: %i)"),
|
|
upstream_node_info.node_name, upstream_node_info.node_id);
|
|
failover_state = FAILOVER_STATE_NONE;
|
|
|
|
return true;
|
|
|
|
case FAILOVER_STATE_FOLLOW_FAIL:
|
|
/*
|
|
* for whatever reason we were unable to follow the new primary -
|
|
* continue monitoring in degraded state
|
|
*/
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
|
|
return false;
|
|
|
|
default:
|
|
monitoring_state = MS_DEGRADED;
|
|
INSTR_TIME_SET_CURRENT(degraded_monitoring_start);
|
|
|
|
return false;
|
|
}
|
|
/* should never reach here */
|
|
return false;
|
|
}
|
|
|
|
|
|
static void
|
|
reset_node_voting_status(void)
|
|
{
|
|
failover_state = FAILOVER_STATE_NONE;
|
|
|
|
if (PQstatus(local_conn) != CONNECTION_OK)
|
|
{
|
|
log_error(_("reset_node_voting_status(): local_conn not set"));
|
|
return;
|
|
}
|
|
reset_voting_status(local_conn);
|
|
}
|
|
|
|
|
|
static void
|
|
check_connection(t_node_info *node_info, PGconn **conn)
|
|
{
|
|
if (is_server_available(node_info->conninfo) == false)
|
|
{
|
|
log_warning(_("connection to node %i lost"), node_info->node_id);
|
|
}
|
|
|
|
if (PQstatus(*conn) != CONNECTION_OK)
|
|
{
|
|
log_info(_("attempting to reconnect to node \"%s\" (ID: %i)"),
|
|
node_info->node_name,
|
|
node_info->node_id);
|
|
*conn = establish_db_connection(node_info->conninfo, false);
|
|
|
|
if (PQstatus(*conn) != CONNECTION_OK)
|
|
{
|
|
*conn = NULL;
|
|
log_warning(_("reconnection to node \"%s\" (ID: %i) failed"),
|
|
node_info->node_name,
|
|
node_info->node_id);
|
|
}
|
|
else
|
|
{
|
|
log_info(_("reconnected to node \"%s\" (ID: %i)"),
|
|
node_info->node_name,
|
|
node_info->node_id);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
static const char *
|
|
format_failover_state(FailoverState failover_state)
|
|
{
|
|
switch(failover_state)
|
|
{
|
|
case FAILOVER_STATE_UNKNOWN:
|
|
return "UNKNOWN";
|
|
case FAILOVER_STATE_NONE:
|
|
return "NONE";
|
|
case FAILOVER_STATE_PROMOTED:
|
|
return "PROMOTED";
|
|
case FAILOVER_STATE_PROMOTION_FAILED:
|
|
return "PROMOTION_FAILED";
|
|
case FAILOVER_STATE_PRIMARY_REAPPEARED:
|
|
return "PRIMARY_REAPPEARED";
|
|
case FAILOVER_STATE_LOCAL_NODE_FAILURE:
|
|
return "LOCAL_NODE_FAILURE";
|
|
case FAILOVER_STATE_WAITING_NEW_PRIMARY:
|
|
return "WAITING_NEW_PRIMARY";
|
|
case FAILOVER_STATE_REQUIRES_MANUAL_FAILOVER:
|
|
return "REQUIRES_MANUAL_FAILOVER";
|
|
case FAILOVER_STATE_FOLLOWED_NEW_PRIMARY:
|
|
return "FOLLOWED_NEW_PRIMARY";
|
|
case FAILOVER_STATE_FOLLOWING_ORIGINAL_PRIMARY:
|
|
return "FOLLOWING_ORIGINAL_PRIMARY";
|
|
case FAILOVER_STATE_NO_NEW_PRIMARY:
|
|
return "NO_NEW_PRIMARY";
|
|
case FAILOVER_STATE_FOLLOW_FAIL:
|
|
return "FOLLOW_FAIL";
|
|
case FAILOVER_STATE_NODE_NOTIFICATION_ERROR:
|
|
return "NODE_NOTIFICATION_ERROR";
|
|
}
|
|
|
|
/* should never reach here */
|
|
return "UNKNOWN_FAILOVER_STATE";
|
|
}
|
|
|
|
|