1. mysql mutual master and slave architecture
1.1 Experimental environment
1.1.1 Both server systems are centos7
1.1.2 Server IP distribution
MySQL Server1 : 192.168.153.135
MySQL Server2 : 192.168.153.136
1.1.3 Before the experiment, the server is closed firewall and selinux
Turn off the firewall command:
systemctl stop firewalld
Close the selinux command:
setenforce 0
1.1.4 Specific configuration: centos7 is the same as centos6
The centos7 installation database client name is: mariadb, and the server name is: mariadb-server
yum -y install mariadb-server mariadb
Reference link >> https://blog.csdn.net/m0_46674735/article/details/109597636
2. Keepalived preemption mode configuration
2.1 Install keepalived software on both servers
yum -y install keepalived
2.2 Modify the keepalived configuration file on Server1
2.2.1 Modify command
vim /etc/keepalived/keepalived.conf
2.2.2 The revised content is as follows:
1) Comment out vrrp_strict on line 14, the comment symbol is!
The meaning of the vrrp_strict parameter is:
strictly abide by the VRRP protocol. The following conditions will prevent Keepalived from starting: 1. There is no VIP address. 2. Unicast neighbors. 3. There are IPv6 addresses in VRRP version 2. Need to comment out here
2) Configure vrrp_instance
3) Configure virtual_server
2.2.3 After the modification is completed, save and exit and start the keepalived service
systemctl start keepalived
2.3 Modify the keepalived configuration file on Server1
2.3.1 Modify command
vim /etc/keepalived/keepalived.conf
2.3.2 The revised content is as follows:
1) Comment out vrrp_strict on line 14, the comment symbol is!
The meaning of the vrrp_strict parameter is:
strictly abide by the VRRP protocol. The following conditions will prevent Keepalived from starting: 1. There is no VIP address. 2. Unicast neighbors. 3. There are IPv6 addresses in VRRP version 2. Need to comment out here
2) Configure vrrp_instance
3) Configure virtual_server
2.3.3 After the modification is completed, save and exit and start the keepalived service
systemctl start keepalived
3. Verify the configuration
3.1 Is the VIP configured successfully on server1
command:ip add
3.2 Verify VIP drift
3.2.1 Shut down the mysql service on server1,
[root@host-135 ~]# systemctl stop mariadb
3.2.2 Check VIP drift success on server2
3.3 Preemption mode verification
3.3.1 Recover mysql service and keepalived service on server1
[root@host-135 ~]# systemctl start mariadb
[root@host-135 ~]# systemctl start keepalived
3.3.2 Checking the success of VIP preemption
3.4 Detailed information can be viewed in the trace log
command:tailf /var/log/messages
3.4.1 server1 enters the master state
3.4.2 server2 enters the backup state
3.4.3 After the MySQL service on server1 is stopped, server2 preempts as master
3.4.3 After the MySQL service and keepalived service on server1 are restored, server1 is preempted as master again
And server2 is restored to backup state
4. Keepalived non-preemptive mode configuration
4.1 Modify the keepalived configuration file on Server1
4.2.1 Modify command
vim /etc/keepalived/keepalived.conf
4.2.2 The revised content is as follows:
Modify the status of server1 to BACKUP, and add a line of parameter nopreempt to
save and exit after the modification is complete
4.2.3 Restart the keepalived service
systemctl restart keepalived
4.2 Modify the keepalived configuration file on Server2
4.2.1 Modify command
vim /etc/keepalived/keepalived.conf
4.2.2 The revised content is as follows:
Just add another line of parameter nopreempt
and save and exit after the modification is complete
4.2.3 Restart the keepalived service
systemctl restart keepalived
4.3 Verification
4.3.1 Verify that the VIP setting on the 135 host is successful
4.3.2 Verify VIP drift
Stop the mysql service on the 135 host
[root@host-135 ~]# systemctl stop mariadb
Check drift success on 136 host
4.3.3 Non-preemptive mode verification
1) Restore mysql service and keepalived service on 135 host
[root@host-135 ~]# systemctl start mariadb keepalived
2) Viewing VIP on 135 host will not drift back
3) Stopping the mysql service on the 136 host and VIP drifting
[root@host-136 ~]# systemctl stop mariadb
4) Viewing VIP on 135 host will drift back again
