实验环境:redhat6.5
server1:172.25.20.1 server2:172.25.20.2
server3:172.25.20.3 server4:172.25.20.4
又一个避免单点故障的方法:将DR添加到HA的keepalived中。keepalived对后端有健康检查,则在安装好keepalived之后可直接添加DR。
1.源码安装keepalived
[root@server1 ~]# tar zxf keepalived-1.3.5.tar.gz
cd keepalived-1.2.24
[root@server1 keepalived-1.3.5]# ./configure --prefix=/usr/local/keepalived --with-init=SYSV
首次编码出错, yum installopenssl-devel.x86_64 gcc -y
[root@server1 keepalived-1.3.5]# make && make install
cd /usr/local
scp -r keepalived 172.25.20.4:/usr/local
[root@server1 ~]# ln -s /usr/local/keepalived/sbin/keepalived /sbin/keepalived #二进制文件的软链接
[root@server1 ~]# ln -s /usr/local/keepalived/etc/keepalived/ /etc/ #主配置文件的软链接
[root@server1 ~]# ln -s /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/#配置文件的软链接
[root@server1 ~]# ln -s /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/#启动脚本的软链接
[root@server1 ~]# chmod +x /usr/local/keepalived/etc/rc.d/init.d/keepalived
2.将DR添加到keepalived及测试
[root@server1 ~]# vim /etc/keepalived/keepalived.conf
1 ! Configuration Filefor keepalived
2
3 global_defs {
4 notification_email {
5 root@localhost #邮件接受端
6 }
7 notification_email_from keepalived@server1#邮件发送端
8 smtp_server 127.0.0.1 #本地回环
9 smtp_connect_timeout 30 #连接超时
10 router_id LVS_DEVEL
11 vrrp_skip_check_adv_addr
12 vrrp_strict
13 vrrp_garp_interval 0
14 vrrp_gna_interval 0
15 }
16
17 vrrp_instance VI_1 {
18 state MASTER #server1是master
19 interface eth0 #进入接口eth0
20 virtual_router_id 20 #虚拟路由id(1-254之间)
21 priority 100 #在启动keepalived服务时,系统会比较priority的值,哪个值大哪个就是master
22 advert_int 1
23 authentication {
24 auth_type PASS
25 auth_pass 1111
26 }
27 virtual_ipaddress {
28 172.25.20.100 #虚拟ip
29 }
30
31
32 virtual_server172.25.20.100 80 { #虚拟服务
33 delay_loop 6
34 lb_algo rr
35 lb_kind DR #DR
36 # persistence_timeout 50 #超时
37 protocol TCP
38
39 real_server 172.25.20.2 80 { #真正的服务端
40 weight 1 #权重
41 TCP_CHECK {
42 connect_timeout 3
43 nb_get_retry 3
44 delay_before_retry 3
45 }
46 }
47 real_server 172.25.20.3 80 { #真正的服务端
48 weight 1
49 TCP_CHECK {
50 connect_timeout 3
51 nb_get_retry 3
52 delay_before_retry 3
53 }
54 }
55
56 }
[root@server1 ~]# /etc/init.d/keepalived start
[root@server1 ~]# scp /etc/keepalived/keepalived.conf172.25.20.4:/etc/keepalived/ #将其传到server4
[root@server4 ~]# ln -s /usr/local/keepalived/sbin/keepalived /sbin/keepalived
[root@server4 ~]# ln -s /usr/local/keepalived/etc/keepalived/ /etc/
[root@server4 ~]# ln -s /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
[root@server4 ~]# ln -s /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
[root@server4 ~]# chmod +x /usr/local/keepalived/etc/rc.d/init.d/keepalived
[root@server4 ~]# vim /etc/keepalived/keepalived.conf
7 notification_email_from keepalived@server4#邮件发送段,本机
18 state BACKUP #备服务器
21 priority 50 #优先级
[root@server2 local]# /etc/init.d/keepalived star
测试:
当主机keepalived停掉,系统会将服务转移到备机上;当主机重新打开时,系统会重新读配置文件,来确定主机和备机,将服务开启到主机上
[root@server1 ~]# /etc/init.d/keepalived stop
[root@server1 ~]# ip addr show #查看,虚拟ip不在server1
[root@server4 ~]# iptables -F
[root@server4 ~]# ip addr show
curl 172.25.20.100 ##物理机访问
[root@server2 ~]# /etc/init.d/httpd stop
[root@server3 ~]# /etc/init.d/httpd stop
server2 server3相继关闭http服务,本地回环