為了使repmgr正常運行，需要對postgresql.conf進行配置
# 監聽所有網段，默認為 localhost ，只監聽本地的連接
listen_addresses = '*'
# 數據庫監聽端口設置為 5432
port = 5432
# 最大的流復制連接數，一般為備數據庫連接數量，同時 pg_basebackup 需要通過流復制連接進行備份
max_wal_senders = 32
# 最多使用的復制槽數量
max_replication_slots = 32
# 最少保留的 WAL 日志數量
wal_keep_segments = 512
# WAL 日志級別，級別越高記錄的日志越多，數據庫至少配置為 replica，PostgreSQL 9.5和更早版本為hot_standby或者logical
wal_level = 'replica' 或 'logical'
# 開啟熱備模式，備數據庫接受讀連接
hot_standby = on
# 備數據庫查詢事務反饋給主數據庫，防止因為數據變化導致查詢中斷，repmgr需要能夠連接到它管理的每台服務器。
hot_standby_feedback = on
# 開啟歸檔
archive_mode = on
# 歸檔命令，將 WAL 日志拷貝到歸檔目錄 xxxx/archive 下
archive_command = 'test ! -f xxxx/archive/%f && cp %p xxxx/archive/%f'
# 數據頁變動時，將整個數據頁寫入 WAL 日志，執行 sys_rewind 時需要
full_page_writes = on
# 執行 sys_rewind 時需要
wal_log_hints = on
# 開啟數據庫日志收集
logging_collector = on
# 日志格式為 csv 格式
log_destination = 'csvlog'
# 日志文件存儲路徑為數據目錄下的 log 目錄
log_directory = 'log'
# 預加載 lib 庫文件，需要將 repmgr 庫寫入此變量，可以寫多個庫文件，以 ',' 進行分隔
shared_preload_libraries = 'repmgr'
舉例
1、數據庫配置
listen_addresses = '*' port = 5432 max_wal_senders = 32 max_replication_slots = 32 wal_keep_segments = 512 wal_level = 'replica' hot_standby = on hot_standby_feedback = on archive_mode = on archive_command = 'test ! -f /var/lib/pgsql/12/archive/%f && cp %p /var/lib/pgsql/12/archive/%f' full_page_writes = on wal_log_hints = on logging_collector = on log_destination = 'csvlog' log_directory = 'log' shared_preload_libraries = 'repmgr'
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pg_hba.conf
host replication all 0.0.0.0/0 trus
2、主機repmgr.conf
node_id=1 node_name='node1' conninfo='host=192.168.101.9 port=5432 user=postgres dbname=postgres' data_directory='/var/lib/pgsql/12/data'
3、查詢主機狀態
[postgres@localhost bin]$ ./repmgr cluster show ID | Name | Role | Status | Upstream | Location | Priority | Timeline | Connection string ----+-------+---------+-----------+----------+----------+----------+----------+------------------------------------------------------------- 1 | node1 | primary | * running | | default | 100 | 1 | host=192.168.101.9 port=5432 user=postgres dbname=postgres
4、備機repmgr.conf
node_id=2 node_name='node2' conninfo='host=192.168.101.7 port=5432 user=postgres dbname=postgres' data_directory='/home/postgres/pgsql/12/data''
5、克隆備機，調用的pg_basebackup進行備機創建
[postgres@localhost bin]$ ./repmgr standby clone -h 192.168.101.9 -Upostgres NOTICE: destination directory "/home/postgres/pgsql/12/data" provided INFO: connecting to source node DETAIL: connection string is: host=192.168.101.9 user=postgres DETAIL: current installation size is 24 MB NOTICE: checking for available walsenders on the source node (2 required) NOTICE: checking replication connections can be made to the source server (2 required) INFO: creating directory "/home/postgres/pgsql/12/data"... NOTICE: starting backup (using pg_basebackup)... HINT: this may take some time; consider using the -c/--fast-checkpoint option INFO: executing: /usr/pgsql-12/bin/pg_basebackup -l "repmgr base backup" -D /home/postgres/pgsql/12/data -h 192.168.101.9 -p 5432 -U postgres -X stream NOTICE: standby clone (using pg_basebackup) complete NOTICE: you can now start your PostgreSQL server HINT: for example: pg_ctl -D /home/postgres/pgsql/12/data start HINT: after starting the server, you need to register this standby with "repmgr standby register"
6、啟動並注冊備機
#啟動
./pg_ctl -D /home/postgres/pgsql/12/data start
#注冊 [postgres@localhost bin]$ ./repmgr standby register INFO: connecting to local node "node2" (ID: 2) INFO: connecting to primary database WARNING: --upstream-node-id not supplied, assuming upstream node is primary (node ID 1) INFO: standby registration complete NOTICE: standby node "node2" (ID: 2) successfully registered
7、集群狀態檢查
