mirror of
https://github.com/EnterpriseDB/repmgr.git
synced 2026-03-23 07:06:30 +00:00
README.md: minor corrections
This commit is contained in:
49
README.md
49
README.md
@@ -4,8 +4,8 @@ repmgr: Replication Manager for PostgreSQL
|
||||
`repmgr` is a suite of open-source tools to manage replication and failover
|
||||
within a cluster of PostgreSQL servers. It enhances PostgreSQL's built-in
|
||||
replication capabilities with utilities to set up standby servers, monitor
|
||||
replication, and perform administrative tasks such as failover or manual
|
||||
switchover operations.
|
||||
replication, and perform administrative tasks such as failover or switchover
|
||||
operations.
|
||||
|
||||
|
||||
Overview
|
||||
@@ -55,7 +55,7 @@ of PostgreSQL servers connected by streaming replication.
|
||||
|
||||
- `node`
|
||||
|
||||
A `node` is a server within a network cluster.
|
||||
A `node` is a server within a replication cluster.
|
||||
|
||||
- `upstream node`
|
||||
|
||||
@@ -64,9 +64,9 @@ the case of cascading replication, another standby.
|
||||
|
||||
- `failover`
|
||||
|
||||
If a master server fails, generally it's desirable to promote a suitable
|
||||
standby as the new master. The `repmgrd` daemon supports automatic failover
|
||||
in this kind of case.
|
||||
This is the action which occurs if a master server fails and a suitable standby
|
||||
is promoted as the new master. The `repmgrd` daemon supports automatic failover
|
||||
to minimise downtime.
|
||||
|
||||
- `switchover`
|
||||
|
||||
@@ -137,7 +137,7 @@ The `repmgr` tools must be installed on each server in the replication cluster.
|
||||
|
||||
A dedicated system user for `repmgr` is *not* required; as many `repmgr` and
|
||||
`repmgrd` actions require direct access to the PostgreSQL data directory,
|
||||
it is usually executed by the `postgres` user.
|
||||
it should executed by the `postgres` user.
|
||||
|
||||
Additionally, we recommend installing `rsync` and enabling passwordless
|
||||
`ssh` connectivity between all servers in the replication cluster.
|
||||
@@ -177,17 +177,18 @@ infrastructure, e.g.:
|
||||
|
||||
sudo make USE_PGXS=1 install
|
||||
|
||||
`repmgr` can be built in any environment suitable for building PostgreSQL itself.
|
||||
`repmgr` can be built from source in any environment suitable for building
|
||||
PostgreSQL itself.
|
||||
|
||||
|
||||
### Configuration
|
||||
|
||||
`repmgr` and `repmgrd` use a common configuration file, usually named
|
||||
`repmgr` and `repmgrd` use a common configuration file, by default called
|
||||
`repmgr.conf` (although any name can be used if explicitly specified).
|
||||
At the very least, `repmgr.conf` must contain the connection parameters
|
||||
for the local `repmgr` database.
|
||||
|
||||
The configuration file will be looked for in the following locations:
|
||||
The configuration file will be searched for in the following locations:
|
||||
|
||||
- a configuration file specified by the `-f/--config-file` command line option
|
||||
- `repmgr.conf` in the local directory
|
||||
@@ -196,12 +197,12 @@ The configuration file will be looked for in the following locations:
|
||||
|
||||
Note that if a file is explicitly specified with `-f/--config-file`, an error will
|
||||
be raised if it is not found or not readable and no attempt will be made to check
|
||||
default locations.
|
||||
default locations; this is to prevent `repmgr` reading the wrong file.
|
||||
|
||||
For a full list of annotated configuration items, see the file `repmgr.conf.sample`.
|
||||
|
||||
These parameters in the configuration file can be overridden with command line
|
||||
options:
|
||||
The following parameters in the configuration file can be overridden with
|
||||
command line options:
|
||||
|
||||
- `-L/--log-level`
|
||||
- `-b/--pg_bindir`
|
||||
@@ -248,6 +249,11 @@ The following replication settings must be included in `postgresql.conf`:
|
||||
hot_standby = on
|
||||
|
||||
|
||||
*TIP*: rather than editing these settings in the default `postgresql.conf`
|
||||
file, create a separate file such as `postgresql.replication.conf` and
|
||||
include it from the end of the main configuration file with:
|
||||
`include 'postgresql.replication.conf'`
|
||||
|
||||
Create a dedicated PostgreSQL superuser account and a database for
|
||||
the `repmgr` metadata, e.g.
|
||||
|
||||
@@ -352,11 +358,12 @@ Clone the standby with:
|
||||
|
||||
This will clone the PostgreSQL data directory files from the master using
|
||||
PostgreSQL's pg_basebackup utility. A `recovery.conf` file containing the
|
||||
correct parameters to start streaming from the master server will
|
||||
be created automatically, and unless otherwise the `postgresql.conf` and `pg_hba.conf`
|
||||
correct parameters to start streaming from the master server will be created
|
||||
automatically, and unless otherwise the `postgresql.conf` and `pg_hba.conf`
|
||||
files will be copied.
|
||||
|
||||
Make any adjustments to the configuration files now, then start the standby server.
|
||||
Make any adjustments to the PostgreSQL configuration files now, then start the
|
||||
standby server.
|
||||
|
||||
*NOTE*: `repmgr standby clone` does not require `repmgr.conf`, however we
|
||||
recommend providing this as `repmgr` will set the `application_name` parameter
|
||||
@@ -396,7 +403,7 @@ Register the standby server with:
|
||||
repmgr -f /etc/repmgr.conf standby register
|
||||
[2016-01-08 11:13:16] [NOTICE] standby node correctly registered for cluster test with id 2 (conninfo: host=repmgr_node2 user=repmgr dbname=repmgr)
|
||||
|
||||
Connect to the standby servers' `repmgr` database and check the `repl_nodes`
|
||||
Connect to the standby server's `repmgr` database and check the `repl_nodes`
|
||||
table:
|
||||
|
||||
repmgr=# SELECT * FROM repmgr_test.repl_nodes ORDER BY id;
|
||||
@@ -410,8 +417,8 @@ The standby server now has a copy of records for all servers in the replication
|
||||
cluster. Note that the relationship between master and standby is explicitly
|
||||
defined via the `upstream_node_id` value, which shows here that the standby's
|
||||
upstream server is the replication cluster master. While of limited use
|
||||
in a simple 2-level master/standby replication cluster, this information is
|
||||
required to effectively manage cascading replication (see below).
|
||||
in a simple master/standby replication cluster, this information is required
|
||||
to effectively manage cascading replication (see below).
|
||||
|
||||
|
||||
Advanced options for cloning a standby
|
||||
@@ -423,8 +430,8 @@ over the cloning process may be necessary.
|
||||
|
||||
### pg_basebackup options when cloning a standby
|
||||
|
||||
By default, `pg_basebackup` performs a checkpoint before beginning the
|
||||
backup process. However, a normal checkpoint may take some time to complete;
|
||||
By default, `pg_basebackup` performs a checkpoint before beginning the backup
|
||||
process. However, a normal checkpoint may take some time to complete;
|
||||
a fast checkpoint can be forced with `repmgr`'s `-c/--fast-checkpoint`
|
||||
option. This may impact performance of the server being cloned from
|
||||
so should be used with care.
|
||||
|
||||
Reference in New Issue
Block a user