Keepalived高可用+邮件告警
Keepalived高可用
| IP | 主机名 | 备注 |
|---|---|---|
| 192.168.117.14 | keepalived-master | 主节点 |
| 192.168.117.15 | keepalived-slaver | 备节点 |
| 192.168.117.100 | VIP |
1.主备节点均安装keepalived
# yum install -y keepalived httpd
2.主备节点均修改keepalived日志存放路径
# vim /etc/sysconfig/keepalived //修改如下
KEEPALIVED_OPTIONS="-D -d -S 0"
# vim /etc/rsyslog.conf //在local7.*一行下加一行配置
local0.* /var/log/keepalived.log
# systemctl restart rsyslog //重启rsyslog以生效
3.进入主节点，编辑keepalived配置文件
[root@keepalived-master ~]# vim /etc/keepalived/keepalived.conf
global_defs {
notification_email {
[email protected] //接收告警的人
}
notification_email_from [email protected] //发邮件地址
smtp_server 127.0.0.1 //发邮件地址
smtp_connect_timeout 30
router_id LVS_DEVEL
vrrp_skip_check_adv_addr
vrrp_strict
vrrp_garp_interval 0
vrrp_gna_interval 0
}
#此处添加一段监控httpd服务的配置
vrrp_script check_httpd {
script "/usr/local/sbin/check_httpd.sh"
interval 3 //脚本执行间隔，单位：秒
}
vrrp_instance VI_1 {
state MASTER //节点身份
interface ens33 //对应监听VIP的网卡
virtual_router_id 51
priority 100 //权重，master的值要比backup大
advert_int 1
authentication {
auth_type PASS
auth_pass 12345678 //密码
}
virtual_ipaddress {
192.168.117.100 //设置VIP
}
#此处添加一段定义监控脚本
track_script {
check_httpd
}
}
4.编写监控httpd服务的脚本，赋予执行权限
[root@keepalived-master ~]# vim /usr/local/sbin/check_httpd.sh
#!/bin/bash
DATE=`date +'%F_%T'`
PROC=`ps -C httpd --no-heading | wc -l`
if [ $PROC -eq "0" ]; then
systemctl start httpd
PROC2=`ps -C httpd --no-heading | wc -l`
if [ $PROC2 -eq "0" ]; then
echo "$DATE httpd down,keepalived will stop!" >> /var/log/check_httpd.log
systemctl stop keepalived
fi
fi
[root@keepalived-master ~]# chmod +x /usr/local/sbin/check_httpd.sh
5.启动httpd服务和keepalived服务，查看是否自动为网卡配置上了VIP
[root@keepalived-master ~]# systemctl start httpd
[root@keepalived-master ~]# systemctl start keepalived
[root@keepalived-master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:0c:29:52:42:6f brd ff:ff:ff:ff:ff:ff
inet 192.168.117.14/24 brd 192.168.117.255 scope global noprefixroute ens33
valid_lft forever preferred_lft forever
inet 192.168.117.100/32 scope global ens33
valid_lft forever preferred_lft forever
inet6 fe80::421a:43b7:1f73:55d9/64 scope link noprefixroute
valid_lft forever preferred_lft forever
6.进入备节点，编辑keepalived配置文件，与主节点的配置基本相同，备注的几处不同
[root@keepalived-slaver ~]# vim /etc/keepalived/keepalived.conf
global_defs {
notification_email {
[email protected]
}
notification_email_from [email protected]
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
vrrp_skip_check_adv_addr
vrrp_strict
vrrp_garp_interval 0
vrrp_gna_interval 0
}
vrrp_script check_httpd {
script "/usr/local/sbin/check_httpd.sh"
interval 3
}
vrrp_instance VI_1 {
state BACKUP //节点身份
interface ens33 //对应监听VIP的网卡
virtual_router_id 51
priority 90 //权重，要比主节点的值低
advert_int 1
authentication {
auth_type PASS
auth_pass 12345678
}
virtual_ipaddress {
192.168.117.100
}
track_script {
check_httpd
}
}
7.同样需要配置监控脚本
[root@keepalived-slaver ~]# vim /usr/local/sbin/check_httpd.sh
#!/bin/bash
DATE=`date +'%F_%T'`
PROC=`ps -C httpd --no-heading | wc -l`
if [ $PROC -eq "0" ]; then
systemctl start httpd
PROC2=`ps -C httpd --no-heading | wc -l`
if [ $PROC2 -eq "0" ]; then
echo "$DATE httpd down,keepalived will stop!" >> /var/log/check_httpd.log
systemctl stop keepalived
fi
fi
[root@keepalived-slaver ~]# chmod +x /usr/local/sbin/check_httpd.sh
8.启动keepalived服务
[root@keepalived-slaver ~]# systemctl start keepalived
9.测试
测试1：httpd服务自动启动
[root@keepalived-master ~]# systemctl stop httpd //主节点关闭httpd
[root@keepalived-master ~]# ps -C httpd //发现很快httpd又启动了
PID TTY TIME CMD
23513 ? 00:00:00 httpd
23515 ? 00:00:00 httpd
23516 ? 00:00:00 httpd
23517 ? 00:00:00 httpd
23518 ? 00:00:00 httpd
23519 ? 00:00:00 httpd
测试2：模拟主节点宕机
[root@keepalived-master ~]# systemctl stop keepavlied //主节点关闭keepalived，模拟宕机
[root@keepalived-slaver ~]# ip a //进入备节点查看ens33网卡，发现自动配置上了VIP
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:0c:29:d4:b5:f5 brd ff:ff:ff:ff:ff:ff
inet 192.168.117.15/24 brd 192.168.117.255 scope global noprefixroute ens33
valid_lft forever preferred_lft forever
inet 192.168.117.100/32 scope global ens33
valid_lft forever preferred_lft forever
inet6 fe80::e075:8f2b:ed7c:ca78/64 scope link noprefixroute
valid_lft forever preferred_lft forever
配置邮件告警（主备节点都以相同方式配置，以主节点为例）
1.安装sendmail
[root@keepalived-master ~]# yum install -y sendmail* mailx
2.修改邮件配置
[root@keepalived-master ~]# vim /etc/mail.rc //添加如下配置
set from=[email protected]
set smtp=smtp.qq.com
set smtp-auth-user=[email protected]
set smtp-auth-password=xxxxxxxxxxxxxxxx //授权码
set smtp-auth=login
3.编写邮件告警脚本
[root@keepalived-master ~]# vim /usr/local/sbin/check_keepalived.sh
#!/bin/bash
EMAIL='[email protected]'
DATE=`date +'%F_%T'`
TITLE="`hostname` is $1 now"
CONTENT="${DATE}: `hostname` to be $1"
if (($1=='master'|'backup')); then
echo "${CONTENT}" | mail -s "${TITLE}" ${EMAIL}
else
echo "something error!" | mail -s "${TITLE}" ${EMAIL}
fi
4.修改keepalived配置文件
[root@keepalived-master ~]# vim /etc/keepalived/keepalived.conf //在vrrp_instance VI_1这段配置尾部加上两行邮件告警配置
notify_master "/bin/bash /usr/local/sbin/check_keepalived.sh master"
notify_backup "/bin/bash /usr/local/sbin/check_keepalived.sh backup"
5.重启sendmail服务及keepalived服务
[root@keepalived-master ~]# systemctl restart sendmail
[root@keepalived-master ~]# systemctl restart keepalived
6.关闭主节点测试邮件告警
