标签：nginx+keepalived 双机双主热备 ha可用性
上篇文章我们配置的双机热备，意思是说两台机器一台处于运行中，另一台永久处于备份。这样的话资源浪费严重，适用于国企,政府类系统。今天我们所讲的是双机双主热备，意味着两台机器同时处于工作状态，两台主机又同时为备份状态。
两台主机192.168.100.128/24 192.168.100.129/24
两个单独的ip 192.168.100.133/24 192.168.100.134/24
可以将你域名解析到这两个单独的ip,keepalived会将这两个ip通过虚拟ip技术漂移到两台主机上。如果一台机器down，keepalived会将原本漂移在它身上的ip,漂移到另一台机器上，这样就实现了双机双主互为主机和备份。
安装可以查看我的上篇文章：nginx+keepalived实现双机热备高可用性 http://blog.csdn.net/caicongyang/article/details/46444007
global_defs {
notification_email {
1491318829@qq.com
}
notification_email_from keepalived@localhost.com
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_script chk_http_port {
script "/opt/nginx_pid.sh"
interval 2
weight -20 #每检查一次，权重减去20
}
vrrp_instance VI_1 {
state MASTER
interface eth1 #注意看到你本机的网络接口
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
track_script {
chk_http_port
}
virtual_ipaddress {
192.168.100.133
}
}
vrrp_instance VI_2 {
state BACKUP
interface eth1 #两处都为本机的网络接口
virtual_router_id 52
priority 99 #权重
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.100.134/24
}
}
global_defs {
notification_email {
1491318829@qq.com #接收警报的email地址,可以添加多个
}
notification_email_from admin@caicongyang.com ###发件人地址
smtp_server 127.0.0.1 ###发送邮件的服务器
smtp_connect_timeout 30 ###超时时间
router_id LVS_DEVEL ####load balancer 的标识 ID,用于email警报
}
vrrp_script chk_http_port {
script "/opt/nginx_pid.sh" ####检测nginx状态的脚本路径
interval 2
weight -20
}
vrrp_instance VI_1 {
state BACKUP
interface eth2
virtual_router_id 51
priority 99
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.100.133/24
}
}
vrrp_instance VI_2 {
state MASTER
interface eth2
virtual_router_id 52
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
track_script {
chk_http_port
}
virtual_ipaddress {
192.168.100.134/24
}
}#/usr/local/nginx/sbin/nginx启动keepalived
#service keepalived start
#ip a
1: lo: <LOOPBACK,UP,LOWER_UP> 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: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:ff:ca:24 brd ff:ff:ff:ff:ff:ff
inet 192.168.100.128/24 brd 192.168.100.255 scope global eth1
inet 192.168.100.133/32 scope global eth1
inet6 fe80::20c:29ff:feff:ca24/64 scope link
valid_lft forever preferred_lft forever
1: lo: <LOOPBACK,UP,LOWER_UP> 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: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:c0:02:92 brd ff:ff:ff:ff:ff:ff
inet 192.168.100.129/24 brd 192.168.100.255 scope global eth2
inet 192.168.100.134/24 scope global secondary eth2
inet6 fe80::20c:29ff:fec0:292/64 scope link
valid_lft forever preferred_lft forever
1: lo: <LOOPBACK,UP,LOWER_UP> 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: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:c0:02:92 brd ff:ff:ff:ff:ff:ff
inet 192.168.100.129/24 brd 192.168.100.255 scope global eth2
inet 192.168.100.134/24 scope global secondary eth2
inet 192.168.100.133/24 scope global secondary eth2
inet6 fe80::20c:29ff:fec0:292/64 scope link
valid_lft forever preferred_lft forever#tail -f /var/log/messages
后记：这两边nginx+keepalied高可用性的文章中，我们配置了notification_email但是都没用到，楼主将在下篇文章配置smtp服务，让其生效，这样就能在服务发生异常的情况下，发送邮件提醒运维人员。当然博主我也会在后期发布免费网络监视工具Nagios的相关文章，将其整合进来，具体利弊后期分析。
不懂运维的程序员，不是好的工程师！
我的个人网站：http://www.caicongyang.com
我的CSDN博客地址： http://blog.csdn.net/caicongyang
标签：nginx+keepalived 双机双主热备 ha可用性
原文地址：http://blog.csdn.net/caicongyang/article/details/46468397
