Previously it would refuse to start if the primary was not reachable,
the thinking being that it's pointless trying to monitor an incomplete
cluster.
However following an aborted failover situation, repmgrd will restart
monitoring and on the witness server, this will lead to it aborting
itself due to to continuing absence of primary.
To resolve this, witness repmgrd will now start monitoring in degraded
mode if no primary is found in the hope a primary will reappear at
some point.
Previously repmgr would abort with an unhelpful message about being
unable to parse CSV output.
With this commit, it will continue running, and display a list of
inaccessible nodes as an addendum to the main output (unless --csv
or --terse options are specified).
Addresses GitHub #246.
This is to facilitate remote invocation of repmgr when the repmgr
binary is located somewhere other than the PostgreSQL binary directory, as it
cannot be assumed all package maintainers will install repmgr there.
This parameter is optional; if not set (the default), repmgr will fall back
to "pg_bindir" (if set).
Addresses GitHub #246.
Previously, "repmgr standby switchover" used the configuration file parameters
"reconnect_interval" and "reconnect_attempts" to define a timeout to determine
whether the current primary (demotion candidate) has shut down.
However, these parameters are intended for primary failure detection and are
generally lower in value, while a controlled shutdown may take longer, resulting
in the switchover being aborted as repmgr was not waiting long enough.
To prevent this happening, parameter "shutdown_check_timeout" has been added.
This complements the existing "standby_reconnect_timeout" parameter used
by "repmgr standby switchover".
Implements GitHub #504.
Previously, if the server being monitored was not available, repmgrd
would always close the existing connection handle and open a new one.
However, in some cases, e.g. a brief network outage, the existing
connection handle is still good and does not need to be reopened.
This could be particularly problematic if monitoring_history is on,
as this risks leaving orphan sessions on the primary which (given
a sufficiently unstable network) could lead to all available backends
being occupied.
Instead, during an outage we now use a new connection to verify
the server is accessible; if the old connection is still available
(e.g. following a short network interruption) we continue using that;
if not (e.g. the server was restarted), we use the new one.
Previously query texts were always logged at log level DEBUG, but
that doesn't help much in a normal production environment when
trying to identify the cause of issues.
Also make various other minor improvements to query logging and
handling of database errors.
Implements GitHub #498.
Previously repmgr would first check that a replication can be made
from the demotion candidate to the promotion candidate, however it's
preferable to sanity-check the number of available walsenders first,
to provide a more useful error message.
Avoid copying files during a --dry-run as it may introduce unexpected changes
on the target node. During an actual clone operation, any problems with
copying files will be detected early and the operation aborted before
the actual database cloning commences.
GitHub #491.
Some distributions may add extra information to PG_VERSION after
the actual version number (e.g. "10.4 (Debian 10.4-2.pgdg90+1)"), so
copy the version number string up until the first space is found.
GitHub #490.
This suppresses log output below log level ERROR. This is useful mainly
when repmgr is being executed programmatically, e.g. in a cronjob,
where it's only useful to receive output if something goes wrong.
Note we advise against using this option when executing repmgr
commands which operate on PostgreSQL nodes (standby follow,
standby promote, standby switchover, node rejoin), particularly when
executed by repmgrd, as the log output will provide valuable
troubleshooting information.
Implements suggestion in GitHub #468.
Default was previously NOTICE (as in repmgr 3.x) but documentation
implied it was INFO, and many of the the documentation examples assume
it is.
This produces some quite informative log output, without creating excessive
log file volume. In particular it's useful to get a better idea of what
repmgrd is actually doing.
Also add documentation section for the log configuration parameters.
GitHub #470, containing change suggested in GitHub #467.
If any issues are detected (e.g. node not reachable, unexpected node status
etc.), "repmgr cluster show" returns exit code 25 ("ERR_NODE_STATUS").
Note that exit code 25 was introduced recently as "ERR_CLUSTER_CHECK",
however it makes sense to use this to indicate issues detected by any
command which can detect node issues.
Addresses GitHub #456.
The default value for "wait_register_sync_seconds" was zero, which is treated
as disabling --wait-sync altogether. Default value now set to -1, which is taken
to mean no timeout value supplied.
This matches the behaviour of other PostgreSQL utilities such as psql, though
repmgr will only abort once all command line options are parsed, so as many
errors as possible are found and displayed. If a repmgr "command" (e.g.
"repmgr primary ..." was provided, a hint about the relevant command
help section (e.g. "repmgr primary --help") will be provided alongside
the generic help command (i.e. "repmgr --help").
Addresses GitHub #464, with further improvements.
It's hard to imagine a use case where this isn't desirable, but
in case, for whatever reason, the user does not wish to daemonize the
process, the command line option "--daemonize=false" can be provided.
Implements GitHub #458.
If two nodes were in the primary location, and at least one node in
another location, the non-failed node in the primary location was not
recognising itself as a promotion candidate.
Addresses GitHub #407.
During a switchover operation, once the demoted primary has been restarted
as a standby, repmgr attempts to reconnect to verify its status and drop
any redundant replication slots. However it's possible the standby may still
be in the startup phase, so poll for "standby_reconnect_timeout" seconds
before giving up.
Addresses GitHub #408.
Insert "connect_timeout=2" into the connection parameters, if not
explicitly set by the user. This will prevent excessive wait time
for the host operating system to report a connection timeout.
