Keepalived setting does not preempt resources

keepalived do HA when , We often encounter preemptive master and backup Switch between

example:

Usually if master After the service died backup Will become master, But when master When the service is better again master Preemption occurs VIP, In this way, there will be two switches, which is not good for busy websites . So we need to add... To the configuration file   nopreempt  non-preemptive , But this parameter can only be used for state by backup, So we're using HA It's the best time to master and backup Of state Set up backup Let it go through priority To compete .

Be careful ： After this configuration , We should pay attention to starting keepalived The order of services , Suppose I want A Become backup Then you can't start it first A Of keepalived service .

Here is the combination MHA Architecture master 、 Standby database configuration example

Main library

[[email protected] ~]# more /etc/keepalived/keepalived.conf #20140916 #!/bin/bash

global_defs {     router_id mysqlmha }

vrrp_script check_run {   script "/etc/keepalived/check_mysql.sh"   interval 1 }

vrrp_instance VI_1 {     state BACKUP    -- The status here is specified as backup     interface eth0     virtual_router_id 151     priority 100     advert_int 1     nopreempt        -- Set up nopreempt Prevent preemption of resources     authentication {         auth_type PASS         auth_pass 1111     }

    track_script {         check_run     }     virtual_ipaddress {         192.168.66.53     } }

For the library

[[email protected] ~]# more /etc/keepalived/keepalived.conf ! Configuration File for keepalived

global_defs {   router_id mysqlmha }

vrrp_script check_run {   script "/etc/keepalived/check_mysql.sh"   interval 1 }

vrrp_instance VI_1 {     state BACKUP     interface eth0     virtual_router_id 151     priority 90     advert_int 1     authentication {         auth_type PASS         auth_pass 1111     }

    track_script {       check_run     }

    virtual_ipaddress {         192.168.66.53     } }