mysql基于vip的主备切换_mysql主备切换[高可用]
到这一步的时候, 是主备部署已经处理好, 请关注:mysql主备部署[高可用]
这次使用的是keepalived-1.2.22.tar.gz版, 官网地址:keeplived官网
笼统知识请自行查询百度下面开始步骤
第一步:安装keepalived-1.2.22
解压
tar -zxvf keepalived-1.2.22.tar.gz
编译
cd keepalived-1.2.22
./configure --prefix=/usr/local/keepalived/(新建文件夹喔)
安装
make && make install
服务脚本
cp /usr/local/etc/rc.d/init.d/keepalived /etc/init.d/keepalived
配置文件
cp /usr/local/keepalived/etc/keepalived.conf /etc/keepalived/keepalived.conf
服务
cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/keepalived
加入服务
chkconfig --add keepalived
chkconfig keepalived on
service keepalived start #启动服务
service keepalived stop #停止服务
service keepalived restart #重启服务
上面的额操作主备机器都需要安装
第二步:配置文件
master:keepalived.conf
! Configuration File for keepalived
global_defs {
router_id HA_MySQL
}
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 51
priority 100
advert_int 1
nopreempt
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.88.88
}
}
virtual_server 192.168.88.88 3306 {
delay_loop 2
lb_algo wrr
lb_kind DR
persistence_timeout 60
protocol TCP
real_server 192.168.75.61 3306 {
weight 3
notify_down /etc/keepalived/down.sh
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
}
slave:keepalived.conf
! Configuration File for keepalived
global_defs {
router_id HA_MySQL
}
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 51
priority 90
advert_int 1
nopreempt
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.88.88
}
}
virtual_server 192.168.88.88 3306 {
delay_loop 2
lb_algo wrr
lb_kind DR
persistence_timeout 60
protocol TCP
real_server 192.168.75.62 3306 {
weight 3
# echo"62....1"
notify_down /etc/keepalived/down.sh
# notify_up /etc/keepalived/up.sh
# echo"62....2"
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
}
down:down.sh
#!/bin/bash
pkill keepalived
第三步:测试
主:192.168.75.61
备:192.168.75.62
主:
[root@qwzs08 log]#service mysqld start
[root@qwzs08 log]#service keeplived start
保证已经启动成功!
[root@qwzs08 log]#ip addr
会显示出下面的vip(我上面配置文件把master放在61)
1: lo: mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: mtu 1500 qdisc mq state UNKNOWN qlen 1000
link/ether 00:50:56:89:a3:28 brd ff:ff:ff:ff:ff:ff
inet 192.168.75.61/24 brd 192.168.75.255 scope global eth0
inet 192.168.88.88/32 scope global eth0
inet6 fe80::250:56ff:fe89:a328/64 scope link
valid_lft forever preferred_lft forever
表示vip正常
此时在备机
[root@qwzs07 log]#ip addr
1: lo: mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: mtu 1500 qdisc mq state UNKNOWN qlen 1000
link/ether 00:50:56:89:cb:a6 brd ff:ff:ff:ff:ff:ff
inet 192.168.75.62/24 brd 192.168.75.255 scope global eth0
inet6 fe80::250:56ff:fe89:cba6/64 scope link
valid_lft forever preferred_lft forever
是没有vip的, 恭喜您!配置成功!
第四步:漂移
模拟主机宕机
ps aux | grep mysqld
root 1176 0.0 0.0 11336 1408 ? S 15:38 0:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --datadir=/usr/local/mysql/data --pid-file=/usr/local/mysql/data/mysql3306.pid
mysql 1591 7.1 1.8 2736136 597708 ? Sl 15:38 3:19 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/usr/local/mysql/data/mysql3306.err --pid-file=/usr/local/mysql/data/mysql3306.pid
root 1978 0.0 0.0 103248 844 pts/0 S+ 16:24 0:00 grep mysql
kill -9 1176 1591
此时,主机的mysql挂掉了,您怎么确定是有没有漂移呢?
查一下vip
ip addr
1: lo: mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: mtu 1500 qdisc mq state UNKNOWN qlen 1000
link/ether 00:50:56:89:cb:a6 brd ff:ff:ff:ff:ff:ff
inet 192.168.75.61/24 brd 192.168.75.255 scope global eth0
inet6 fe80::250:56ff:fe89:cba6/64 scope link
valid_lft forever preferred_lft forever
已经没有了
再去备机查一下vip
ip addr
1: lo: mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: mtu 1500 qdisc mq state UNKNOWN qlen 1000
link/ether 00:50:56:89:a3:28 brd ff:ff:ff:ff:ff:ff
inet 192.168.75.62/24 brd 192.168.75.255 scope global eth0
inet 192.168.88.88/32 scope global eth0
inet6 fe80::250:56ff:fe89:a328/64 scope link
valid_lft forever preferred_lft forever
look, 漂过来了
现在切换到主机把的mysql和keeplived开启
此时主机的服务已经开起来了, 但是vip并没有漂过去, 这就是nopreempt的作用, 防止脑裂
这时候加入备机slave挂掉, vip就会漂移到主机master, 实现高可用主从切换
此时如果能实现漂移就是成功了, 下面是我遇到的问题
1.keepalived执行后日志狂刷, 2.脚本并没有执行(down.sh),具体情况就是mysql挂掉后,keeplived并没有自杀,导致vip漂移失败, 但是手动关闭keeplived后会实现漂移, 原因就在于down脚本没有得到执行。
日志报错:
Nov 21 16:05:27 qwzs08 abrt[13378]: Not saving repeating crash in '/usr/sbin/keepalived'
Nov 21 16:05:27 qwzs08 Keepalived_healthcheckers: IPVS: Can't initialize ipvs: Protocol not available
Nov 21 16:05:27 qwzs08 Keepalived_healthcheckers: Netlink reflector reports IP 192.168.75.62 added
Nov 21 16:05:27 qwzs08 Keepalived_healthcheckers: Netlink reflector reports IP 192.168.75.62 added
Nov 21 16:05:27 qwzs08 Keepalived_healthcheckers: Registering Kernel netlink reflector
Nov 21 16:05:27 qwzs08 Keepalived_healthcheckers: Registering Kernel netlink command channel
Nov 21 16:05:27 qwzs08 Keepalived_healthcheckers: Opening file '/etc/keepalived/keepalived.conf'.
Nov 21 16:05:27 qwzs08 Keepalived_healthcheckers: Configuration is using : 9635 Bytes
很纠结,经过排查,原因是ip_vs模块系统默认没有自动加载
执行命令:
查看
lsmod | grep ip_vs
(如果没有任何输出则表示ip_vs模块并没有被内核加载)
手动加载
modprobe ip_vs
modprobe ip_vs_wrr
然后再看日志已经恢复正常
此时再查看ip_vs
lsmod | grep ip_vs
ip_vs_wrr 2179 1
ip_vs 115643 3 ip_vs_wrr
libcrc32c 1246 1 ip_vs
ipv6 321422 68 ip_vs,ip6t_REJECT,nf_conntrack_ipv6,nf_defrag_ipv6
ok!