主备（keepalived+haproxy)

系统：centos6.9 mini

主机名    ip                                虚拟ip

kh1     192.168.126.210

kh2     192.168.126.220                     192.168.126.100

web11   192.168.126.230

web22   192.168.126.240

1、在kh1和kh2安装keepalived和haproxy

[root@kh1 ~]# yum install -y keepavlivd haproxy

[root@kh2 ~]# yum install -y keepavlivd haproxy

2、在web1和web2上部署web服务

[root@web11 ~]# yum install -y httpd

[root@web11 ~]# echo "web1">/var/www/html/index.html

[root@web11 ~]# service httpd restart

[root@web11 ~]# chkconfig httpd on

[root@web22 ~]# yum install -y httpd

[root@web22 ~]# echo "web2">/var/www/html/index.html

[root@web22 ~]# service httpd restart

[root@web22 ~]# chkconfig httpd on

3、在kh1和kh2 配置keepalived，在kh1上查看虚拟ip

[root@kh1 ~]# cat /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {

router_id kh1

}

vrrp_instance VI_1 {

state MASTER

interface eth0

virtual_router_id 51

priority 100

advert_int 1

authentication {

auth_type PASS

auth_pass 1111

}

virtual_ipaddress {

192.168.126.100

}

}

[root@kh1 ~]# /etc/init.d/keepalived restart

[root@kh1 ~]# ip addr list

link/ether 00:0c:29:da:01:36 brd ff:ff:ff:ff:ff:ff

inet 192.168.126.210/24 brd 192.168.126.255 scope global eth0

inet 192.168.126.100/32 scope global eth0

[root@kh2 ~]# cat /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {

router_id kn2

}

vrrp_instance VI_1 {

state BACKUP

interface eth0

virtual_router_id 51

priority 90

advert_int 1

authentication {

auth_type PASS

auth_pass 1111

}

virtual_ipaddress {

192.168.126.100

}

}

[root@kh2 ~]# /etc/init.d/keepalived restart

4、在kh1和kh2上配置haproxy（两个节点的配置一样的，红色部分为添加部分）

[root@kh1 ~]# cat /etc/haproxy/haproxy.cfg

#---------------------------------------------------------------------

# Example configuration for a possible web application.  See the

# full configuration options online.

#

#   http://haproxy.1wt.eu/download/1.4/doc/configuration.txt

#

#---------------------------------------------------------------------

#---------------------------------------------------------------------

# Global settings

#---------------------------------------------------------------------

global

# to have these messages end up in /var/log/haproxy.log you will

# need to:

#

# 1) configure syslog to accept network log events.  This is done

#    by adding the '-r' option to the SYSLOGD_OPTIONS in

#    /etc/sysconfig/syslog

#

# 2) configure local2 events to go to the /var/log/haproxy.log

#   file. A line like the following can be added to

#   /etc/sysconfig/syslog

#

#   local2.*                       /var/log/haproxy.log

#

log         127.0.0.1 local2

chroot      /var/lib/haproxy

pidfile     /var/run/haproxy.pid

maxconn     4000

user        haproxy

group       haproxy

daemon

# turn on stats unix socket

stats socket /var/lib/haproxy/stats

#---------------------------------------------------------------------

# common defaults that all the 'listen' and 'backend' sections will

# use if not designated in their block

#---------------------------------------------------------------------

defaults

mode                    http

log                       global

option                  httplog

option                  dontlognull

option http-server-close

option forwardfor       except 127.0.0.0/8

option                  redispatch

retries                 3

timeout http-request    10s

timeout queue           1m

timeout connect         10s

timeout client             1m

timeout server            1m

timeout http-keep-alive     10s

timeout check             10s

maxconn                 3000

stats uri               /haproxy-stats    #监控页面的url

stats refresh           30s             #更新页面时间

stats auth              admin:admin    #监控页面的提示信息

stats hide-version                       #隐藏统计页面上的HAproxy版本信息

#---------------------------------------------------------------------

# main frontend which proxys to the backends

#---------------------------------------------------------------------

frontend  http_80_in

bind *:80       #监听端口，即haproxy提供web服务的端口，和lvs的vip端口类似

mode http    #http的7层模式

log global

default_backend      test1

#---------------------------------------------------------------------

# static backend for serving up images, stylesheets and such

#---------------------------------------------------------------------

#backend static

#    balance     roundrobin

#---------------------------------------------------------------------

# round robin balancing between the various backends

#---------------------------------------------------------------------

backend  test1

balance     roundrobin

server        web11 192.168.126.230:80 weight 1 check inter 15000 rise 2 fall 4

server      web22 192.168.126.240:80 weight 2 check inter 15000 rise 2 fall 4

#web集群配置，服务器定义web11,webv22 ,check inter 1500是检测心跳频率rise 2是2次正确认为服务器可用，

fall 4是4次失败认为服务器不可用，weight代表权重

[root@kh1 ~]# scp /etc/haproxy/haproxy.cfg root@192.168.126.220:/etc/haproxy/haproxy.cfg

#复制配置文件到kh2上

[root@kh1 ~]# /etc/init.d/haproxy restart

[root@kh2 ~]# /etc/init.d/haproxy restart

5、验证

5.1 在kh1上关掉keepalived和haproxy 服务，vip 转移到kh2上，后端服务正常

[root@kh1 ~]# /etc/init.d/keepalived stop

Stopping keepalived:                                       [  OK  ]

[root@kh1 ~]# /etc/init.d/haproxy stop

Stopping haproxy:

[root@kh2 ~]# ip addr list

2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

link/ether 00:0c:29:80:2e:09 brd ff:ff:ff:ff:ff:ff

inet 192.168.126.220/24 brd 192.168.126.255 scope global eth0

inet 192.168.126.100/32 scope global eth0

inet6 fe80::20c:29ff:fe80:2e09/64 scope link

valid_lft forever preferred_lft forever

[root@kh2 ~]# curl http://192.168.126.100

web2

[root@kh2 ~]# curl http://192.168.126.100

web2

[root@kh2 ~]# curl http://192.168.126.100

web1

5.2 访问haproxy 监控页面,最浏览器输入http://192.168.126.100/haproxy-stats  ,填入用户名admin和密码admin（图一）,接着看到的是监控的页面（图二），可以看到web11，web2都是up的，当web11 宕机了，再次刷新，可以看到web11的状态是down 的，颜色变成了红色（图三）

图一

图二

图三