keepalived+lvs(为lvs提供健康检查)

【注】：所有实验机的防火墙和sellinux都要关闭

keepalived+lvs+httpd

调度端(keepalived)：server1（172.25.9.1） server2(172.25.9.2)
real server:server3(172.25.9.3) server4(172.25.9.4)

调度端（serevr1&server2）

关闭HA服务，清除arp规则

[root@server1 ~]# /etc/init.d/heartbeat stop
Stopping High-Availability services: Done.
[root@server1 ~]# ipvsadm -C
[root@server1 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn

安装keepalived服务

[root@server1 ha.d]# yum install keepalived -y
[root@server1 sysconfig]# ll /etc/init.d/keepalived 
-rwxr-xr-x 1 root root 2134 Sep 26  2012 /etc/init.d/keepalived
[root@server1 sysconfig]# ll /etc/sysconfig/keepalived 
-rw-r--r-- 1 root root 667 Sep 26  2012 /etc/sysconfig/keepalived

修改keepalived配置文件

[root@server1 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   notification_email {				#指定keepalived在发生切换时需要发送email到的目标，一行一个
        root@localhost				#用户名@主机名
}
   notification_email_from keepalived@server1.example.com	#指定发件人
   smtp_server 127.0.0.1					#指定smtp服务器地址
   smtp_connect_timeout 30					#指定smtp连接超时时间
   router_id LVS_DEVEL			#运行keepalived机器的一个标识
}

vrrp_instance VI_1 {			
    state MASTER		      #指定master和backup，如果设置了nopreempt这个值不起作用，主备考priority决定
    interface eth1		     #设置实例绑定的网卡
    virtual_router_id 51	 #VPID标记
    priority 100		          #优先级，高的优先级竞选为master
    advert_int 1		#检查间隔，默认1秒
    authentication {		#设置认证
        auth_type PASS		#认证方式
        auth_pass 1111		#认证密码
    }
  virtual_ipaddress {		#设置vip
        172.25.9.100
    }
}

virtual_server 172.25.9.100 80 {	
    delay_loop 6		#健康检查时间间隔
    lb_algo rr			#lvs调度算法rr|wrr|lc|wlc|lblc|sh|dh
    lb_kind DR			#负载均衡转发规则NAT|DR|RUN
#    nat_mask 255.255.255.0	
#    persistence_timeout 50	#会话保持时间
    protocol TCP		#使用的协议

    real_server 172.25.9.3 80 {
        weight 1		#默认为1，失效为0
        TCP_CHECK {
            connect_timeout 3	#连接超时时间
            nb_get_retry 3	#重连次数
            delay_before_retry 3	#重连间隔时间
        }
    }
  real_server 172.25.9.4 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}

将修改好的配置文件发送给server2

[root@server1 ~]# scp /etc/keepalived/keepalived.conf 172.25.9.2:/etc/keepalived/
做如下改动：
notification_email_from keepalived@server2.example.com
state BACKUP

RS端

1.配置文件

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[root@server3 html]# tail -n 2 /etc/sysctl.conf 
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.all.arp_ignore = 1

2.开启httpd服务

1	[root@server3 ~]# /etc/init.d/httpd start

开启两端服务

1 2	[root@server1 ~]# /etc/init.d/keepalived start [root@server2 ~]# /etc/init.d/keepalived start

实验结果

1.查看服务启动之后的日志：可以看到进入主备状态：

[root@server1 ~]# tail /var/log/messages
Feb 28 19:19:48 server1 Keepalived_healthcheckers[2447]: SMTP alert successfully sent.
Feb 28 19:19:49 server1 Keepalived_vrrp[2448]: VRRP_Instance(VI_1) Entering MASTER STATE
[root@server2 mail]# tail /var/log/messages
Feb 28 19:25:40 server2 Keepalived_vrrp[4457]: VRRP_Instance(VI_1) Entering BACKUP STATE
``` 
2.vip在server1上：

[root@server1 ~]# ip addr show
2: eth1: mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 52:54:00:9a:d3:95 brd ff:ff:ff:ff:ff:ff
inet 172.25.9.1/24 brd 172.25.9.255 scope global eth1
inet 172.25.9.100/32 scope global eth1

1 2	3.自动生成arp规则

[root@server1 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 172.25.9.100:80 rr
-> 172.25.9.3:80 Route 1 0 0
-> 172.25.9.4:80 Route 1 0 0


## keepalived+lvs+ftp

只是将上面管理的服务修改为ftp服务

### RS端(server3&server4)
1.安装vsftpd服务，并创建测试文件

[root@server3 ~]# yum install vsftpd -y
[root@server3 ~]# cd /var/ftp/pub/
[root@server3 pub]# touch server3
[root@server3 pub]# /etc/init.d/vsftpd start

1 2	### 调度端（server1&server2） 1.修改配置文件（server1）

[root@server1 ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@server1.example.com
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}

vrrp_instance VI_1 {
state MASTER
interface eth1
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
172.25.9.100
}
}

virtual_server 172.25.9.100 21 {
delay_loop 6
lb_algo rr
lb_kind DR

nat_mask 255.255.255.0

 persistence_timeout 50                #
 protocol TCP

real_server 172.25.9.3 21 {
    weight 1
    TCP_CHECK {
        connect_timeout 3
    }
}
real_server 172.25.9.4 21 {
    weight 1
    TCP_CHECK {
        connect_timeout 3
    }
}

}

1 2	2.将配置文件发送给server2并修改

[root@server1 ~]# scp /etc/keepalived/keepalived.conf 172.25.9.2:/etc/keepalived/
做如下改动：
notification_email_from keepalived@server2.example.com
state BACKUP

1 2	3.重启keepalived服务

[root@server1 ~]# /etc/init.d/keepalived restart

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3


4.实验结果
vip在master上：

[root@server1 ~]# ip addr show

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3


调度端的arp规则：
server1:

[root@server1 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 172.25.9.100:21 rr
-> 172.25.9.3:21 Route 1 0 0
-> 172.25.9.4:21 Route 1 0 0

server2:

[root@server1 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 172.25.9.100:21 rr persistent 50
-> 172.25.9.3:21 Route 1 0 0
-> 172.25.9.4:21 Route 1 1 8

1 2	在物理机上lftp vip：

[root@foundation187 ~]# lftp 172.25.9.100
lftp 172.25.9.100:~> ls /pub/
-rw-r–r– 1 0 0 0 Feb 28 15:17 server4

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2


过50秒后：

[root@foundation187 ~]# lftp 172.25.9.100
lftp 172.25.9.100:~> ls /pub/
-rw-r–r– 1 0 0 0 Feb 28 15:17 server3
```