Patroni高可用VIP方案

一 机器和vip资源

PostgreSQL

pg1: 192.168.56.105

pg2: 192.168.56.106

etcd

etcd: 192.168.56.104

vip

读写vip: 192.168.56.111

二 通过callback脚本实现vip漂移

客户端通过vip的方式访问PostgreSQL数据库可以多一层防护，Patroni支持用户配置在特定事件发生时触发的回调脚本。因此可以配置一个回调，在主备切换后动态加载vip。

加载vip的回调脚本/pgsql/loadvip.sh

pg1和pg2实例如下

[root@localhost ~]# cat /pgsql/loadvip.sh

#!/bin/bash

VIP=192.168.56.111

GATEWAY=192.168.56.1

DEV=enp0s8

action=$1

role=$2

cluster=$3

log()

{

  echo "loadvip: $*"|logger

}

load_vip()

{

ip a|grep -w ${DEV}|grep -w ${VIP} >/dev/null

if [ $? -eq 0 ] ;then

  log "vip exists, skip load vip"

else

  sudo ip addr add ${VIP}/32 dev ${DEV} >/dev/null

  rc=$?

  if [ $rc -ne 0 ] ;then

    log "fail to add vip ${VIP} at dev ${DEV} rc=$rc"

    exit 1

  fi

  log "added vip ${VIP} at dev ${DEV}"

  arping -U -I ${DEV} -s ${VIP} ${GATEWAY} -c 5 >/dev/null

  rc=$?

  if [ $rc -ne 0 ] ;then

    log "fail to call arping to gateway ${GATEWAY} rc=$rc"

    exit 1

  fi

  log "called arping to gateway ${GATEWAY}"

fi

}

unload_vip()

{

ip a|grep -w ${DEV}|grep -w ${VIP} >/dev/null

if [ $? -eq 0 ] ;then

  sudo ip addr del ${VIP}/32 dev ${DEV} >/dev/null

  rc=$?

  if [ $rc -ne 0 ] ;then

    log "fail to delete vip ${VIP} at dev ${DEV} rc=$rc"

    exit 1

  fi

  log "deleted vip ${VIP} at dev ${DEV}"

else

  log "vip not exists, skip de