双中心容灾

双中心容灾

这里默认双中心的组网如下：

备中心的主节点实际是主中心主节点的异步备机。

停止主中心

停止主中心 adbhamgr（在所有节点上执行）：

sudo systemctl stop adbhamgr

升级备中心

以下操作在任意一个节点执行即可。

• 查看升级前备中心状态，此时备中心的主机为 Standby Leader：

[antdb@localhost ~]$ adbhamgrctl -c /etc/adbhamgr/adbhamgr_antdbcluster.yaml list
+ Cluster: antdbcluster (7240007647780694395) ----+---------+----+-----------+
| Member    | Host               | Role           | State   | TL | Lag in MB |
+-----------+--------------------+----------------+---------+----+-----------+
| adbhamgr-1 | 10.1.206.202:55551 | Replica        | running |  8 |         0 |
| adbhamgr-2 | 10.1.206.213:55551 | Standby Leader | running |  8 |           |
| adbhamgr-3 | 10.1.206.226:55551 | Replica        | running |  8 |         0 |
+-----------+--------------------+----------------+---------+----+-----------+

• 修改备中心的相关配置

使用 edit-config 命令删掉关于备中心（standby_cluster）的相关配置：

adbhamgrctl -c /etc/adbhamgr/adbhamgr_antdbcluster.yaml edit-config
loop_wait: 5
master_start_timeout: 300
maximum_lag_on_failover: 1048576
postgresql:
  parameters:
    hot_standby: 'on'
    log_destination: csvlog
    log_directory: pg_log
    max_connections: 1600
    max_locks_per_transaction: 256
    max_prepared_transactions: 1600
    max_wal_senders: 10
    max_worker_processes: 32
    wal_keep_size: 1024
    wal_level: logical
  use_pg_rewind: true
standby_cluster:              # 删掉这一小节
  create_replica_methods:     # 删掉
  - basebackup                # 删掉
  host: 10.21.10.211          # 删掉
  port: 55551                 # 删掉
  primart_slot_name: adbhamgr  # 删掉
retry_timeout: 5
synchronous_mode: true
synchronous_node_count: 1
ttl: 15

• 查看备中心，已经升级为新主中心，此时新主中心的主机为 Leader：

[antdb@localhost ~]$ adbhamgrctl -c /etc/adbhamgr/adbhamgr_antdbcluster.yaml list
+ Cluster: antdbcluster (7240007647780694395) --+---------+----+-----------+
| Member    | Host               | Role         | State   | TL | Lag in MB |
+-----------+--------------------+--------------+---------+----+-----------+
| adbhamgr-1 | 10.1.206.202:55551 | Sync Standby | running |  9 |         0 |
| adbhamgr-2 | 10.1.206.213:55551 | Leader       | running |  9 |           |
| adbhamgr-3 | 10.1.206.226:55551 | Replica      | running |  9 |         0 |
+-----------+--------------------+--------------+---------+----+-----------+