一、启动MHA
[root@c733 ~]# nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/mha/app1/manager.log 2>&1 &
查看MHA状态
[root@c733 ~]# masterha_check_status --conf=/etc/mha/app1.cnf
关闭MHA
[root@c733 ~]# masterha_stop --conf=/etc/mha/app1.cnf
从库重新加入主库
[root@c733 ~]# grep "CHANGE MASTER TO MASTER" /var/log/mha/app1/manager.log | tail -1
二、测试MHA故障转移
1、停掉c731主库192.168.37.31
[root@c731 ~]# systemctl stop mysql
查看c733的slave状态，发现master_host变成了192.168.37.32
[root@c733 ~]# mysql -uroot -p123456 -e 'start slave;' Warning: Using a password on the command line interface can be insecure. [root@c731 ~]# mysql -uroot -p123456 -e 'show slave status \G' Warning: Using a password on the command line interface can be insecure. *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.37.32 Master_User: rep Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000002 Read_Master_Log_Pos: 231 Relay_Log_File: mysqld-relay-bin.000003 Relay_Log_Pos: 401 Relay_Master_Log_File: mysql-bin.000002 Slave_IO_Running: Yes Slave_SQL_Running: Yes
查看c732的master状态
[root@c732 ~]# mysql -p123456 -e 'show master status;'
三、MHA故障还原
[root@c733 ~]# grep "CHANGE MASTER TO MASTER" /var/log/mha/app1/manager.log | tail -1
Fri Feb 14 02:57:59 2020 - [info] All other slaves should start replication from here. Statement should be: CHANGE MASTER TO MASTER_HOST='192.168.37.31', MASTER_PORT=3306, MASTER_AUTO_POSITION=1, MASTER_USER='rep', MASTER_PASSWORD='xxx';
重启数据库，重新change_master
[root@c731 ~]# systemctl restart mysql [root@c731 ~]# mysql -uroot -p123456 -e "CHANGE MASTER TO MASTER_HOST='192.168.37.32',MASTER_PORT=3306, MASTER_AUTO_POSITION=1,MASTER_USER='rep',MASTER_PASSWORD='123456';" Warning: Using a password on the command line interface can be insecure. [root@c731 ~]# mysql -uroot -p123456 -e 'start slave;' Warning: Using a password on the command line interface can be insecure. [root@c731 ~]# mysql -uroot -p123456 -e 'show slave status \G' Warning: Using a password on the command line interface can be insecure. *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.37.32 Master_User: rep Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000002 Read_Master_Log_Pos: 231 Relay_Log_File: mysqld-relay-bin.000003 Relay_Log_Pos: 401 Relay_Master_Log_File: mysql-bin.000002 Slave_IO_Running: Yes Slave_SQL_Running: Yes
此时，重新在将【server1】标签添加到MHA配置文件，并且重新启动MHA
[root@c733 bin]# sed -i -e '/server2/i \ [server1] \ hostname=192.168.37.31 \ port=3306 \ ' /etc/mha/app1.cnf
[root@c733 ~]# ps -ef | grep mha root 13478 11518 0 03:50 pts/1 00:00:00 grep --color=auto mha [root@c733 ~]# cat /etc/mha/app1.cnf [server default] manager_log=/var/log/mha/app1/manager.log manager_workdir=/var/log/mha/app1 master_binlog_dir=/var/lib/mysql master_ip_failover_script=/usr/bin/master_ip_failover password=mha ping_interval=2 repl_password=123456 repl_user=rep ssh_user=root user=mha [server1] hostname=192.168.37.32 port=3306 [server3] hostname=192.168.37.33 ignore_fail=1 no_master=1 port=3306
发生故障时, MHA做了什么?
①当作为主库的c731.上的MySQL宕机以后, mha通过检测发现c731的mysq|宕机了, 那么会将binlog日志最全的从库
( c732 )立刻提升为主库,而其他的从库会指向新的主库进行再次同步。
②MHA会自己结束自己的进程,还会将/etc/mha/app1.cnf配置文件中,坏掉的那台机器剔除。
四、 配置vip飘逸
1、ip漂移的两种方式：
①通过keepalived的方式，管理虚拟ip的漂移
②通过mha自带脚本的方式，管理虚拟ip的漂移 ，用mha自带的vip漂移脚本，那个提升为主，就漂移到那个上面
要根据binlog最新的slave提升
2、MHA脚本方式
修改MHA配置文件
[root@c733 ~]# cat /etc/mha/app1.cnf [server default] manager_log=/var/log/mha/app1/manager.log manager_workdir=/var/log/mha/app1 master_binlog_dir=/var/lib/mysql master_ip_failover_script=/usr/bin/master_ip_failover //添加此处代码 password=mha ping_interval=2 repl_password=123456 repl_user=rep ssh_user=root user=mha
编写漂移脚本
vim /usr/bin/master_ip_failover
1 [root@c733 bin]# cat master_ip_failover 2 #!/usr/bin/env perl 3 4 use strict; 5 use warnings FATAL => 'all'; 6 7 use Getopt::Long; 8 9 my ( 10 $command, $ssh_user, $orig_master_host, $orig_master_ip, 11 $orig_master_port, $new_master_host, $new_master_ip, $new_master_port 12 ); 13 14 my $vip = '192.168.37.100/24'; 15 my $key = '1'; 16 my $ssh_start_vip = "/sbin/ifconfig ens33:$key $vip"; 17 my $ssh_stop_vip = "/sbin/ifconfig ens33:$key down"; 18 19 GetOptions( 20 'command=s' => \$command, 21 'ssh_user=s' => \$ssh_user, 22 'orig_master_host=s' => \$orig_master_host, 23 'orig_master_ip=s' => \$orig_master_ip, 24 'orig_master_port=i' => \$orig_master_port, 25 'new_master_host=s' => \$new_master_host, 26 'new_master_ip=s' => \$new_master_ip, 27 'new_master_port=i' => \$new_master_port, 28 ); 29 30 exit &main(); 31 32 sub main { 33 34 print "\n\nIN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===\n\n"; 35 36 if ( $command eq "stop" || $command eq "stopssh" ) { 37 38 my $exit_code = 1; 39 eval { 40 print "Disabling the VIP on old master: $orig_master_host \n"; 41 &stop_vip(); 42 $exit_code = 0; 43 }; 44 if ($@) { 45 warn "Got Error: $@\n"; 46 exit $exit_code; 47 } 48 exit $exit_code; 49 } 50 elsif ( $command eq "start" ) { 51 52 my $exit_code = 10; 53 eval { 54 print "Enabling the VIP - $vip on the new master - $new_master_host \n"; 55 &start_vip(); 56 $exit_code = 0; 57 }; 58 if ($@) { 59 warn $@; 60 exit $exit_code; 61 } 62 exit $exit_code; 63 } 64 elsif ( $command eq "status" ) { 65 print "Checking the Status of the script.. OK \n"; 66 exit 0; 67 } 68 else { 69 &usage(); 70 exit 1; 71 } 72 } 73 74 sub start_vip() { 75 `ssh $ssh_user\@$new_master_host \" $ssh_start_vip \"`; 76 } 77 sub stop_vip() { 78 return 0 unless ($ssh_user); 79 `ssh $ssh_user\@$orig_master_host \" $ssh_stop_vip \"`; 80 } 81 82 sub usage { 83 print 84 "Usage: master_ip_failover --command=start|stop|stopssh|status --orig_master_host=host --orig_master_ip=ip --orig_master_port=port --new_master_host=host --new_master_ip=ip --new_master_port=port\n"; 85 }
注意修改脚本中的网卡名和ip地址
192.168.37.100 ens33
添加执行权限
chmod +x /usr/bin/master_ip_failover
3、重启MHA
[root@c733 ~]# masterha_stop --conf=/etc/mha/app1.cnf Stopped app1 successfully. [1]+ 退出 1 nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/mha/app1/manager.log 2>&1 [root@c733 ~]# nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/mha/app1/manager.log 2>&1 & [1] 12132 [root@c733 ~]# masterha_check_status --conf=/etc/mha/app1.cnf app1 (pid:12132) is running(0:PING_OK), master:192.168.37.32
五、模拟主库宕机vip漂移
1、关闭c732上的主库mysql
[root@c732 ~]# ifconfig ens33:1 192.168.37.100/24
[root@c732 ~]# ip a show ens33 2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 00:0c:29:84:52:12 brd ff:ff:ff:ff:ff:ff inet 192.168.37.32/24 brd 192.168.37.255 scope global noprefixroute ens33 valid_lft forever preferred_lft forever inet 192.168.37.100/24 brd 192.168.37.255 scope global secondary ens33:1 valid_lft forever preferred_lft forever inet6 fe80::ea02:b804:fa8f:a8bb/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever inet6 fe80::cefd:32cb:6b50:23c3/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever inet6 fe80::5aae:78b0:a3e4:e112/64 scope link noprefixroute valid_lft forever preferred_lft forever
这里的vip漂移有几秒的延迟
[root@c732 ~]# systemctl stop mysql [root@c732 ~]# ip a show ens33 2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 00:0c:29:84:52:12 brd ff:ff:ff:ff:ff:ff inet 192.168.37.32/24 brd 192.168.37.255 scope global noprefixroute ens33 valid_lft forever preferred_lft forever inet6 fe80::ea02:b804:fa8f:a8bb/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever inet6 fe80::cefd:32cb:6b50:23c3/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever inet6 fe80::5aae:78b0:a3e4:e112/64 scope link noprefixroute valid_lft forever preferred_lft forever
2、现在查看c731上的mysql的master状态和vip
[root@c731 ~]# ip a show ens33 2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 00:0c:29:18:e4:7a brd ff:ff:ff:ff:ff:ff inet 192.168.37.31/24 brd 192.168.37.255 scope global noprefixroute ens33 valid_lft forever preferred_lft forever inet 192.168.37.100/24 brd 192.168.37.255 scope global secondary ens33:1 valid_lft forever preferred_lft forever inet6 fe80::ea02:b804:fa8f:a8bb/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever inet6 fe80::cefd:32cb:6b50:23c3/64 scope link noprefixroute valid_lft forever preferred_lft forever [root@c731 ~]# mysql -p123456 -e 'show master status\G' Warning: Using a password on the command line interface can be insecure. *************************** 1. row *************************** File: mysql-bin.000003 Position: 1256 Binlog_Do_DB: Binlog_Ignore_DB: Executed_Gtid_Set: 986a9807-4e56-11ea-a705-000c29845212:1-6, f27d0522-4e44-11ea-a692-000c2918e47a:1-4