mha能够在10~30秒内实现自动故障检测和故障转移，适用于对高可用性，数据完整性要求较高的场合。要做到无缝切换，还需要依赖于vi
mha能够在10~30秒内实现自动故障检测和故障转移，适用于对高可用性，数据完整性要求较高的场合。要做到无缝切换，还需要依赖于vip漂移。vip漂移比较常用的方式为使用keepalived或者使用脚本直接实现。脚本方式无须安装及复杂配置，，相对简单。本文描述了基于脚本实现vip切换。
对于keepalived的相关配置可以参考：centos 5.9下安装配置keepalived
1、当前主机环境及mha配置
[root@vdbsrv1 ~]# more /etc/hosts
127.0.0.1 localhost.localdomain localhost
192.168.1.6 vdbsrv1 #master
192.168.1.7 vdbsrv2 #slave1
192.168.1.8 vdbsrv3 #slave2
192.168.1.12 vdbsrv4 #manager
###os环境
[root@vdbsrv4 ~]# more /etc/issue
centos release 5.9 (final)
kernel \r on an \m
###mysql环境
[root@vdbsrv4 ~]# mysql -e show variables like 'version'
+---------------+------------+
| variable_name | value |
+---------------+------------+
| version | 5.6.22-log |
+---------------+------------+
[root@vdbsrv4 ~]# masterha_manager --version
masterha_manager version 0.56.
###mha配置信息
[root@vdbsrv4 ~]$ more /etc/masterha/app1.cnf
[server default]
manager_workdir=/var/log/masterha/app1
manager_log=/var/log/masterha/app1/manager.log
user=mha
password=xxx
ssh_user=root
repl_user=repl
repl_password=repl
ping_interval=1
shutdown_script=
master_ip_online_change_script=
report_script=
master_ip_failover_script=/tmp/master_ip_failover
[server1]
hostname=vdbsrv1
master_binlog_dir=/data/mysqldata
[server2]
hostname=vdbsrv2
master_binlog_dir=/data/mysqldata
[server3]
hostname=vdbsrv3
master_binlog_dir=/data/mysqldata/
#candidate_master=1
2、测试vip切换
###测试vip(192.168.1.13)是否被启用
[root@vdbsrv4 ~]# ping 192.168.1.13
ping 192.168.1.13 (192.168.1.13) 56(84) bytes of data.
from 192.168.1.12 icmp_seq=10 destination host unreachable
###为主机vdbsrv1添加vip
[root@vdbsrv4 ~]# ssh vdbsrv1 /sbin/ifconfig eth0:0 192.168.1.13 netmask 255.255.255.0 up
###校验vip是否成功启用
[root@vdbsrv4 ~]# ping 192.168.1.13
ping 192.168.1.13 (192.168.1.13) 56(84) bytes of data.
64 bytes from 192.168.1.13: icmp_seq=1 ttl=64 time=1.82 ms
###开启mha
[root@vdbsrv4 ~]# masterha_manager --conf=/etc/masterha/app1.cnf &
###模拟主库宕机
[root@vdbsrv4 ~]# ssh vdbsrv1 killall -r mysqld
###查看管理节点日志，可以看到vip已经漂移
[root@vdbsrv4 ~]# grep vip /var/log/masterha/app1/manager.log
disabling the vip on old master: vdbsrv1
enabling the vip - 192.168.1.13/24 on the new master - vdbsrv2
###验证vip是否位于节点vdbsrv2
[root@vdbsrv4 ~]# ssh vdbsrv2 ifconfig |grep 1.13 -b1
eth0:0 link encap:ethernet hwaddr 00:0c:29:5f:b2:eb
inet addr:192.168.1.13 bcast:192.168.1.255 mask:255.255.255.0
######查看管理节点mha切换日志
[root@vdbsrv4 ~]# tail /var/log/masterha/app1/manager.log
invalidated master ip address on vdbsrv1(192.168.1.6:3306)
the latest slave vdbsrv2(192.168.1.7:3306) has all relay logs for recovery.
selected vdbsrv2(192.168.1.7:3306) as a new master.
vdbsrv2(192.168.1.7:3306): ok: applying all logs succeeded.
vdbsrv2(192.168.1.7:3306): ok: activated master ip address.
vdbsrv3(192.168.1.8:3306): this host has the latest relay log events.
generating relay diff files from the latest slave succeeded.
vdbsrv3(192.168.1.8:3306): ok: applying all logs succeeded. slave started, replicating from vdbsrv2(192.168.1.7:3306)
vdbsrv2(192.168.1.7:3306): resetting slave info succeeded.
master failover to vdbsrv2(192.168.1.7:3306) completed successfully.
3、vip切换perl脚本
[root@vdbsrv4 app1]# more /tmp/master_ip_failover
#!/usr/bin/env perl
use strict;
use warnings fatal => 'all';
use getopt::long;
my (
$command, $ssh_user, $orig_master_host, $orig_master_ip,
$orig_master_port, $new_master_host, $new_master_ip, $new_master_port
);
my $vip = '192.168.1.13/24';
my $key = '0';
my $ssh_start_vip = /sbin/ifconfig eth0:$key $vip;
my $ssh_stop_vip = /sbin/ifconfig eth0:$key down;
getoptions(
'command=s' => \$command,
'ssh_user=s' => \$ssh_user,
'orig_master_host=s' => \$orig_master_host,
'orig_master_ip=s' => \$orig_master_ip,
'orig_master_port=i' => \$orig_master_port,
'new_master_host=s' => \$new_master_host,
'new_master_ip=s' => \$new_master_ip,
'new_master_port=i' => \$new_master_port,
);
exit &main();
sub main {
print \n\nin script test====$ssh_stop_vip==$ssh_start_vip===\n\n;
if ( $command eq stop || $command eq stopssh ) {