【MySQL】keepalived+haproxy实现mysql的高可用与负载均衡
⒈haproxy检测mysql(难点)
具体方法：将检测脚本提供给xinnetd管理,提供tcp端口（本人采用端口6033）
在/etc/xinetd.d下，创建mysqlchk文件
[root@gz-22 xinetd.d]# pwd
/etc/xinetd.d
[root@gz-22 xinetd.d]# ls -l mysqlchk
-rw-r--r-- 1 root root 370 Jun 2 13:55 mysqlchk
[root@gz-22 xinetd.d]#
mysql文件内容如下：
service mysqlcheck
{
disable = no
flags = REUSE
socket_type = stream
port = 6033
wait = no
user = root
server = /usr/local/etc/mysqlchk_status.sh#此为提供给xinetd管理的脚本
log_type = FILE /dev/null
log_on_failure += USERID
only_from = 192.168.0.0/24
}
Mysqlchk_status.sh检测mysql状态的脚本如下：
[root@gz-22 etc]# more mysqlchk_status.sh
#!/bin/bash
MYSQL_HOST="192.168.0.13"
MYSQL_PORT="3306"
MYSQL_USERNAME="root"
MYSQL_PASSWORD="tianqu"
MYSQL_PATH=mysql #特别注意，这里的脚本要采用绝对路径，本人排错一天时间
STATUS=`$MYSQL_PATH -u$MYSQL_USERNAME -p$MYSQL_PASSWORD -h${MYSQL_HOST} -e "REPAIR TABLE mysql.time_zone\G" 2>/dev/null |awk '/Msg_text/{print $2}'`
if [ "$STATUS" = "OK" ];then
# mysql is fine, return http 200
/bin/echo -e "HTTP/1.1 200 OK\r\n"
/bin/echo -e "Content-Type: Content-Type: text/plain\r\n"
/bin/echo -e "\r\n"
/bin/echo -e "MySQL ($MYSQL_HOST:$MYSQL_PORT) replication is running.\r\n"
/bin/echo -e "\r\n"
else
# mysql is down, return http 503
/bin/echo -e "HTTP/1.1 503 Service Unavailable\r\n"
/bin/echo -e "Content-Type: Content-Type: text/plain\r\n"
/bin/echo -e "\r\n"
/bin/echo -e "MySQL ($MYSQL_HOST:$MYSQL_PORT) replication is *down*.\r\n"
/bin/echo -e "\r\n"
fi
[root@gz-22 etc]#
启动xinetd服务，为让配置生效
[root@gz-22 etc]# /etc/init.d/xinetd restart
我们查看6033端口是否生效
[root@gz-22 etc]# curl -I http://192.168.0.13:6033
HTTP/1.1 200 OK
[root@gz-22 etc]#
也可以用telnet测试，如下：
[root@gz-22 etc]# curl -I http://192.168.0.13:6033
HTTP/1.1 200 OK
[root@gz-22 etc]# telnet 192.168.0.13 6033
Trying 192.168.0.13...
Connected to 192.168.0.13.
Escape character is '^]'.
HTTP/1.1 200 OK
Content-Type: Content-Type: text/plain
MySQL (192.168.0.13:3306) replication is running.
Connection closed by foreign host.
[root@gz-22 etc]#
如出现HTTP/1.1 200 OK字样则表示ok
⒉Haproxy配置
[root@gz-22 etc]# more /usr/local/haproxy/etc/haproxy.conf
global
log 127.0.0.1 local0 info
maxconn 10000
daemon
# ulimit-n 65536
chroot /usr/local/haproxy
pidfile /usr/local/haproxy/run/haproxy.pid
user haproxy
group haproxy
defaults
mode http
option dontlognull
retries 3
option redispatch
maxconn 10000
contimeout 5000
clitimeout 30000
srvtimeout 30000
listen admin_stats
# stats hide-version
bind 0.0.0.0:8082
mode http
stats uri /status
stats realm Global\ statistics
stats auth test:987(*&
listen 8684.cn-Msql-proxy 192.168.0.222:3307
mode tcp
balance roundrobin
option httpchk OPTIONS * HTTP/1.1\n200
server db112 192.168.0.13:3306 weight 1 check port 6033 inter 5s rise 2 fall 2
#端口6033即为上面xinetd定义的端口
server db125 192.168.0.3:3306 weight 1 check port 6033 inter 5s rise 2 fall 2
[root@gz-22 etc]#
3.Keepalived的配置
vrrp_script chk_haproxy {
script "/usr/local/etc/check_haproxy.sh" # cheaper than pidof
interval 2 # check every 2 seconds
weight 2
}
vrrp_instance VI_1 {
interface br0
state MASTER
virtual_router_id 233
priority 100
virtual_ipaddress {
192.168.0.222/24 dev eth1 label eth1:1
}
track_script {
chk_haproxy # +2 if process is present
}
notify_backup "/etc/init.d/haproxy stop"
notify_master "/etc/init.d/haproxy start"
}
关于vrrp_script的weight值，官方没有文档可供参考，但是本人通过测试
vrrp_script在执行时，就会改变priority的值
Jun 5 14:26:49 node1 Keepalived_vrrp[3848]: VRRP_Script(chk_haproxy) succeeded
例如：主第一次启动时，就会改变优先级及priority=weight+priority，以后每interval间隔时间都会做这样一个优先级的累加。所以当你配置vrrp_script不生效时，你的考虑下vrrp设置是否正确
Vrrp_script中的脚本：
[root@node1 ~]# more /usr/local/etc/check_haproxy.sh
#!/bin/bash
sleep 1
REL=`/usr/bin/curl -I -s -u test:987\(*\& http://192.168.0.3:8082/status |head -n1|awk '{print $2}'`
if [ -z "$REL" ] || [ "$REL" -ne 200 ];then
exit 1
else
exit 0
fi
[root@node1 ~]#
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转载于:http://blog.itpub.net/30221425/viewspace-1690180/