db_ha集群添加/删除节点

环境

系统平台：Linux x86-64 Red Hat Enterprise Linux 7
版本：4.5.7

文档用途

本文档用于指导db_ha集群添加/删除节点操作。

详细信息

1、新增节点安装和其他节点同版本数据库

rpm -ivh hgdb4.5.7-see-centos7-x86-64-20220307.rpm

2、安装集群软件

rpm -ivh db_ha4.1.1-see-centos7-x86_64.rpm

3、搭建流复制并启动数据库

pg_basebackup -h x.x.80.228 -U sysdba -D /opt/HighGo4.5.7-see/data -Fp -P -Xs -R -v

pg_ctl start

4、检查该节点流复制状态

ps -ef | grep -v grep | grep walreceive

root      5584  5577  0 10:52 ?        00:00:17 postgres: ha: walreceiver   streaming 0/CE000000

5、从主节点将相关配置文件复制过来

scp /usr/local/db_ha/conf/agent.conf root@ip:/usr/local/db_ha/conf

scp /usr/local/db_ha/conf/agent.conf root@io:/etc/sysconfig

scp /usr/local/db_ha/self_start_service/db_ha-agent.service root@ip:/usr/local/db_ha/self_start_service

scp /usr/local/db_ha/self_start_service/db_ha-agent.service root@ip:/lib/systemd/system

scp /usr/local/db_ha/conf/db_ha.conf root@ip:/usr/local/db_ha/conf

scp ~/.pgpass root@ip:/root

scp ~/.bash_profile root@ip:/root

注意：

确认一下环境变量是否是.bash_profile，也有可能是.bashrc

6、新增节点更改密码文件权限，环境变量生效，设置agent服务开机自启动

chmod 0600 ~/.pgpass

source ~/.bash_profile

systemctl daemon-reload

systemctl enable db_ha-agent.service

7、新增节点启动agent，并加入集群

/usr/local/db_ha/bin/agent  /usr/local/db_ha/conf/agent.conf

db_ha add x.x.80.230  6666 -f /usr/local/db_ha/conf/db_ha.conf -n ha -p 5866 -s

参数注解：

-a, Example Add a standby asynchronization node

-s, Example Add a standby synchronization node

-n [application name], Specifies the application name

8、检查集群

/usr/local/db_ha/bin/db_ha select -f /usr/local/db_ha/conf/db_ha.conf
connect monitor success

cluster num = 3         secondary monitor is normal

nodeip=x.x.80.228,nodetype=PRIMARY,replicationName=node1 streamingType=NONE streamingState=none healthy=t agentState=NORMAL

nodeip=x.x.80.230,nodetype=STANDBY,replicationName=ha streamingType=SYNC streamingState=streaming healthy=t agentState=NORMAL

nodeip=x.x.80.229,nodetype=STANDBY,replicationName=ha streamingType=SYNC streamingState=streaming healthy=t agentState=NORMAL

9、删除节点

db_ha delete x.x.80.230 -f /usr/local/db_ha/conf/db_ha.conf

注意：

①删除节点，集群不会监控该节点，但是该节点数据库运行正常，且正常通过流复制同步数据。

②如果完全删除该节点，做好数据备份，停库，卸载即可。

pg_ctl stop

rpm -e hgdb-see-4.5.7