LVS+Keepalived

#准备环境：
系统：centos6.5 64位 ip 192.168.179.103 主
系统：centos6.5 64位 ip 192.168.179.102 备


#先安装openssl组件，不然提示报错
yum install -y openssl openssl-devel
checking for openssl/ssl.h... no
configure: error:

[root@oldboy tools]# ls -l /usr/src/
total 8
lrwxrwxrwx. 1 root root   39 May 20 17:59 2.6.32-431.el6.x86_64 -> /usr/src/kernels/2.6.32-431.el6.x86_64/
drwxr-xr-x. 2 root root 4096 Sep 23  2011 debug
drwxr-xr-x. 3 root root 4096 May 20 14:17 kernels
lrwxrwxrwx. 1 root root   39 May 20 17:59 linux -> /usr/src/kernels/2.6.32-431.el6.x86_64/

[root@oldboy tools]# tar xf keepalived-1.1.19.tar.gz && cd keepalived-1.1.19
[root@oldboy keepalived-1.1.19]# ./configure
Keepalived configuration
------------------------
Keepalived version       : 1.1.19
Compiler                 : gcc
Compiler flags           : -g -O2
Extra Lib                : -lpopt -lssl -lcrypto 
Use IPVS Framework       : Yes       #ipvs框架
IPVS sync daemon support : Yes       #ipvs同步支持
Use VRRP Framework       : Yes       #VRRP
Use Debug flags          : No



#可能出错
configure: error: Popt libraries is required
yum install popt-devel -y


[root@oldboy keepalived-1.1.19]# make
[root@oldboy keepalived-1.1.19]# make install
[root@oldboy keepalived-1.1.19]# /bin/cp /usr/local/etc/rc.d/init.d/keepalived /etc/init.d/
[root@oldboy keepalived-1.1.19]# /bin/cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
[root@oldboy keepalived-1.1.19]# mkdir /etc/keepalived -p
[root@oldboy keepalived-1.1.19]# /bin/cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/
[root@oldboy keepalived-1.1.19]# /bin/cp /usr/local/sbin/keepalived /usr/sbin/
[root@oldboy keepalived-1.1.19]# /etc/init.d/keepalived start
Starting keepalived:                                       [  OK  ]
[root@oldboy keepalived-1.1.19]# ps -ef | grep keep
root     35874     1  0 14:25 ?        00:00:00 keepalived -D
root     35876 35874  0 14:25 ?        00:00:00 keepalived -D
root     35877 35874  0 14:25 ?        00:00:00 keepalived -D
root     35879 29339  0 14:25 pts/1    00:00:00 grep keep
[root@oldboy keepalived-1.1.19]# /etc/init.d/keepalived stop      #成功后停止keepalived服务；
Stopping keepalived:                                       [  OK  ]


chkconfig  --add keepalived  
chkconfig keepalived  on



#单实例的应用，主服务器的配置文件
cat keepalived.conf
! Configuration File for keepalived

global_defs {          #全局定义
   notification_email {
   493939840@qq.com
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.179.2
   smtp_connect_timeout 30
   router_id LVS_7       #keepalived ID
}

vrrp_instance VI_1 {  #实例VI_1
    state MASTER     #主
    interface eth0  #网卡
    virtual_router_id 55   #实例的id
    priority 150      #优先级
    advert_int 1    #接管时间
    authentication {   #权限，明文密码，官方建议用明文，配置文件可以man keepalived
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {  #VIP地址组
        192.168.179.110/24
    }
}


#备服务器的配置文件
! Configuration File for keepalived

global_defs {
   notification_email {
   493939840@qq.com
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.179.2
   smtp_connect_timeout 30
   router_id LVS_2
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 55
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.179.110/24
    }
}


两台都需安装ipvsadm以及keepalived，ipvsadm只需make install即可，手工配置不需要配置，keepalived接替
两台都需开启服务
[root@oldboy keepalived]# /etc/init.d/keepalived stop
Stopping keepalived:                                       [  OK  ]
#主keepalived
[root@oldboy keepalived]# ip add  #ip add查看
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: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:a5:a3:23 brd ff:ff:ff:ff:ff:ff
    inet 192.168.179.103/24 brd 192.168.179.255 scope global eth0
    inet 192.168.179.110/24 scope global secondary eth0   #vip地址
    inet6 fe80::20c:29ff:fea5:a323/64 scope link 
       valid_lft forever preferred_lft forever
[root@oldboy keepalived]# ip add|grep 179.110
    inet 192.168.179.110/24 scope global secondary eth0   #vip地址

#备keepalived
[root@oldboy keepalived]# ip add
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: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:a3:b8:e2 brd ff:ff:ff:ff:ff:ff
    inet 192.168.179.102/24 brd 192.168.179.255 scope global eth0
    inet6 fe80::20c:29ff:fea3:b8e2/64 scope link 
       valid_lft forever preferred_lft forever    
[root@oldboy keepalived]# ip add|grep 179.110
[root@oldboy keepalived]# 

现在将主的keepalived关掉
[root@oldboy keepalived]# /etc/init.d/keepalived stop
Stopping keepalived:                                       [  OK  ]
看备的状态信息，发现已经接管过来了。大概1秒钟的时间
[root@oldboy keepalived]# ip add
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: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:a3:b8:e2 brd ff:ff:ff:ff:ff:ff
    inet 192.168.179.102/24 brd 192.168.179.255 scope global eth0
    inet 192.168.179.110/24 scope global secondary eth0
    inet6 fe80::20c:29ff:fea3:b8e2/64 scope link 
       valid_lft forever preferred_lft forever

       
这样主备负载均衡就已经实现了

主keepalived配置文件
! Configuration File for keepalived

global_defs {
   notification_email {
   493939840@qq.com
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.179.2
   smtp_connect_timeout 30
   router_id LVS_1
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 51
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.179.110/24
    }
}

vrrp_instance VI_2 {
    state BACKUP
    interface eth0
    virtual_router_id 52
    priority 50
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.179.111/24
    }
}



备keepalived配置文件
! Configuration File for keepalived

global_defs {
   notification_email {
   493939840@qq.com
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.179.2
   smtp_connect_timeout 30
   router_id LVS_1
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.179.110/24
    }
}

vrrp_instance VI_2 {
    state MASTER
    interface eth0
    virtual_router_id 52
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.179.111/24
    }
}

#主备重启服务
[root@oldboy keepalived]# /etc/init.d/keepalived restart
Stopping keepalived:                                       [  OK  ]
Starting keepalived:                                       [  OK  ]
#主节点
[root@oldboy keepalived]# ip add|egrep "179.110|179.111"
    inet 192.168.179.110/24 scope global secondary eth0   #主VIP110，备111

#备节点
[root@oldboy keepalived]# ip add|egrep "179.110|179.111"
    inet 192.168.179.111/24 scope global secondary eth0  #主VIP111，备110
[root@oldboy keepalived]# /etc/init.d/keepalived stop    #停止服务
Stopping keepalived:                                       [  OK  ]

#主节点查看，发现都已经接管了
[root@oldboy keepalived]# ip add|egrep "179.110|179.111"
    inet 192.168.179.110/24 scope global secondary eth0
    inet 192.168.179.111/24 scope global secondary eth0
#备启动服务
[root@oldboy keepalived]# /etc/init.d/keepalived start
Starting keepalived:                                       [  OK  ]
#主节点再次查看，发现已经，但恢复的时间要比接管的时间久，大概5到10秒
[root@oldboy keepalived]# ip add|egrep "179.110|179.111"
    inet 192.168.179.110/24 scope global secondary eth0

#如果只有两台服务器，需要做高可用，那在两台webserver上安装keeplived，再把域名解析到VIP上，需要配置实时同步推送到备节点（比如用户上传的图片，帖子）
#默认情况下keeplived只会监控主机级别的，仅在对方机器down机的情况下接管，不会监控webserver服务down掉，可以自己写守护进程来处理当业务有问题就接管。
#例如在主keeplived中：守护进程，用nmap来检查，如果行数不等于1就stop
#!/bin/sh
while true
do
if[`nmap 127.0.0.1 -p 80|grep open|wc -l` -ne 1]；then
    /etc/init.d/keepalived stop
fi
    sleep 100
done

#执行sh check_web.sh ，ctrl+z退出，bg查看
fg到前台，ctrl+c停掉脚本
#第二个小脚本
#!/bin/bash
while true
do
       httpdpid=`ps -C httpd  --no-heading  |wc -l`
       if [ $httpdpid -eq 0 ];then
               /etc/init.d/httpd  start
               sleep 5
              httpdpid=`ps -C httpd  --no-heading  |wc -l`
               if [ $httpdpid -eq 0 ];then
                       /etc/init.d/keepalive stop
              fi
       fi
       sleep 5
done

[root@oldboy keepalived]# cat /etc/sysconfig/keepalived 
# Options for keepalived. See `keepalived --help‘ output and keepalived(8) and
# keepalived.conf(5) man pages for a list of all options. Here are the most
# common ones :
#
# --vrrp               -P    Only run with VRRP subsystem.
# --check              -C    Only run with Health-checker subsystem.
# --dont-release-vrrp  -V    Dont remove VRRP VIPs & VROUTEs on daemon stop.
# --dont-release-ipvs  -I    Dont remove IPVS topology on daemon stop.
# --dump-conf          -d    Dump the configuration data.
# --log-detail         -D    Detailed log messages.
# --log-facility       -S    0-7 Set local syslog facility (default=LOG_DAEMON)
#

KEEPALIVED_OPTIONS="-D"
KEEPALIVED_OPTIONS="-D -d -S 0"  # -S 指定syslog设备，0就是syslog第一个设备

[root@oldboy keepalived]# tail -1  /etc/rsyslog.conf 
local0.*        /var/log/keepalivend.log  #0.*是指所有的状态信息
#重启rsyslog，重启keepalived （centos 5.X系统中是syslog）
[root@oldboy keepalived]# /etc/init.d/rsyslog restart
Shutting down system logger:                               [  OK  ]
Starting system logger:                                    [  OK  ]
[root@oldboy keepalived]# /etc/init.d/keepalived restart
Stopping keepalived:                                       [  OK  ]
Starting keepalived:                                       [  OK  ]
[root@oldboy keepalived]# tail -5  /var/log/keepalivend.log 
May 22 14:03:52 oldboy Keepalived_vrrp: VRRP_Instance(VI_1) Entering MASTER STATE
May 22 14:03:52 oldboy Keepalived_vrrp: VRRP_Instance(VI_1) setting protocol VIPs.
May 22 14:03:52 oldboy Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.179.110
May 22 14:03:52 oldboy Keepalived_healthcheckers: Netlink reflector reports IP 192.168.179.110 added
May 22 14:03:57 oldboy Keepalived_vrrp: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.179.110


#Keepalived配合Lvs
#############Keepalived配合Lvs##############
1. 如下为备节点：主节点不相同配置标注如下
! Configuration File for keepalived

global_defs {
   notification_email {
   493939840@qq.com
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.179.2
   smtp_connect_timeout 30
   router_id LVS_2                #主为     router_id LVS_1
}

vrrp_instance VI_1 {
    state BACKUP                   #主为MASTER
    interface eth0
    virtual_router_id 51 
    priority 100                   #主为150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.179.110/24            #提供服务的VIP
    }
}

virtual_server 192.168.179.110 80 {    #设置虚拟服务器
    delay_loop 6                     #设置健康状态检查时间
    lb_algo rr                       #设置负载调度算法
    lb_kind DR                       #设置LVS实现负载均衡的机制
    nat_mask 255.255.255.0           #设置掩码
    persistence_timeout 50           #会话保持时间，50秒
    protocol TCP                     #指定转发协议类型
#上面这几行相当于ipvsadm命令，ipvsadm -A -t 192.168.179.110:80 -s rr -p 20     
    sorry_server 127.0.0.1 80        #设置应急服务器  
    real_server 192.168.179.134 80 {   #后端服务器节点
        weight 1                     #设置服务节点的权重
      TCP_CHECK {                   #设置检测方式
            connect_timeout 8        #设置响应超时时间
            nb_get_retry 3           #设置超时重试次数
            delay_before_retry 3     #设置超时重试间隔
            connect_port 80          #TCP端口80
        }
    }
   real_server 192.168.179.135 80 {   #后端服务器节点
        weight 1                     #设置服务节点的权重
      TCP_CHECK {                   #设置检测方式
            connect_timeout 8        #设置响应超时时间
            nb_get_retry 3           #设置超时重试次数
            delay_before_retry 3     #设置超时重试间隔
            connect_port 80          #TCP端口80
        }
    }
}


对于单实例配置文件来讲主备的差别只有三个router_id 、state、 priority、
对于多实例再增加一个主备的stste和priority

#上面这几行相当于ipvsadm命令;
#ipvsadm -a -t 192.168.179.110:80 -r 192.168.179.134 -g -w 1
#ipvsadm -a -t 192.168.179.110:80 -r 192.168.179.135 -g -w 1
#LVS的DR模式不需要内核转发，virtual_server就是VIP地址，LVS本身可以管理，keepalievd也可以管理，但是keepalievd 并不是调用ipvsadm，它有自己的API接口，两台web都需要配置ARP抑制跟VIP绑定
#检测方式有TCP检测80端口，如果80端口不存在，就剔除，也可以http检测，通过url，返回状态码的方式
#两个RS节点全部故障，可以设置应急服务器

2. 两台web服务器配置ARP抑制和绑定VIP脚本
[root@data-1-1 tools]# cat ipvs   
ipvs_rs              ipvsadm-1.26/        ipvsadm-1.26.tar.gz  
[root@data-1-1 tools]# cat ipvs_rs 
#!/bin/sh

VIP=(
192.168.179.110                 #多VIP，添加IP即可
)
. /etc/init.d/functions

case "$1" in
start)
    echo "start LVS of REALServer IP"
    for ((i=0; i<`echo ${#VIP[*]}`; i++))
    do
    interface="lo:`echo ${VIP[$i]}|awk -F . ‘{print $4}‘`"
    /sbin/ifconfig $interface ${VIP[$i]} broadcast ${VIP[$i]} netmask 255.255.255.255 up
    route add -host ${VIP[$i]} dev $interface
    done
     echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore
     echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce
     echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
     echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce 
    ;;
stop)
    for ((i=0; i<`echo ${#VIP[*]}`; i++))
    do
    interface="lo:`echo ${VIP[$i]}|awk -F . ‘{print $4}‘`"
         /sbin/ifconfig $interface ${VIP[$i]} broadcast ${VIP[$i]} netmask 255.255.255.255 down
    route del -host ${VIP[$i]} dev $interface
done
    echo "STOP LVS of REALServer IP"                           #如果是多VIP情况下，不要停止
     echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore
         echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce
         echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore
         echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce
    ;;
*)
  echo "Usage: $0 {start|stop}"
  exit 1
esac

2.1 增加权限，开机自启动
[root@data-1-1 tools]# chmod 700 ipvs_rs 
[root@data-1-1 tools]#  ./ipvs_rs start
[root@data-1-1 tools]# tail -3 /etc/rc.local 
tail: inotify cannot be used, reverting to polling
/application/apache/bin/apachectl start
/home/oldboy/tools/ipvs_rs start
/etc/init.d/keepalived start

3. #两台keepalived重启服务
[root@oldboy keepalived]# /etc/init.d/keepalived restart
Stopping keepalived:                                       [  OK  ]
Starting keepalived:                                       [  OK  ]

#主节点状态
[root@oldboy keepalived-1]# ip add
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: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:a5:a3:23 brd ff:ff:ff:ff:ff:ff
    inet 192.168.179.103/24 brd 192.168.179.255 scope global eth0
    inet 192.168.179.110/24 scope global secondary eth0
    inet6 fe80::20c:29ff:fea5:a323/64 scope link 
       valid_lft forever preferred_lft forever

#备节点状态
[root@oldboy keepalived]# ip add
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: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:a3:b8:e2 brd ff:ff:ff:ff:ff:ff
    inet 192.168.179.102/24 brd 192.168.179.255 scope global eth0
    inet6 fe80::20c:29ff:fea3:b8e2/64 scope link 
       valid_lft forever preferred_lft forever

4. 测试主节点模拟故障
[root@oldboy keepalived]# /etc/init.d/keepalived stop
Stopping keepalived:                                       [  OK  ]
[root@oldboy keepalived]# ipvsadm -L -n
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
 [root@oldboy keepalived]# ip add
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: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:a5:a3:23 brd ff:ff:ff:ff:ff:ff
    inet 192.168.179.103/24 brd 192.168.179.255 scope global eth0
    inet6 fe80::20c:29ff:fea5:a323/64 scope link 
       valid_lft forever preferred_lft forever

#备节点状态，发现已经接管了VIP
[root@oldboy keepalived]# ip add
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: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:a3:b8:e2 brd ff:ff:ff:ff:ff:ff
    inet 192.168.179.102/24 brd 192.168.179.255 scope global eth0
    inet 192.168.179.110/24 scope global secondary eth0
    inet6 fe80::20c:29ff:fea3:b8e2/64 scope link 
       valid_lft forever preferred_lft forever

5. 在主节点测试，然后开启另一个shell窗口 ，web节点停止web服务，查看状态将自动剔除，启动web服务，将自动添加
[root@data-1-1 blog]# watch ipvsadm -L -n
       
    Every 2.0s: ipvsadm -L -n                                    Sat Sep  3 12:22:33 2016

IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.179.110:80 rr persistent 50
  -> 192.168.179.136:80           Local   1     0          0

[root@data-1-2 log]# /application/nginx/sbin/nginx -s reload    #开启服务

[root@data-1-1 blog]# watch ipvsadm -L -n      #再次查看
       
    Every 2.0s: ipvsadm -L -n                                    Sat Sep  3 12:22:33 2016

IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.179.110:80 rr persistent 50
  -> 192.168.179.136:80           Local   1     0          0
  -> 192.168.179.107:80           Route   1     0          0

注：在测试上述步骤的时候遇到如下问题，刚开始用如下命令也报错，后面检查df -h 磁盘写满，清空一些日志释放空间再用如下命令就ok
nginx: [error] invalid PID number "" in "/app/logs/nginx.pid"
[root@data-1-2 log]# 
[root@data-1-2 log]# /application/nginx/sbin/nginx -c /application/nginx/conf/nginx.conf
[root@data-1-2 log]# /application/nginx/sbin/nginx -s reload

#ipvsadmin生产常用命令组合
ipvasdm -Ln --stats
ipvasdm -Lnc
ipvasdm -Ln --thresholds
ipvasdm -Ln --timeout

#nginx+keepalive 高可用web集群
keepalive+nginx 192.168.179.103 主VIP110
keepalive+nginx 192.168.179.136  备VIP110
web 192.168.179.134
web 192.168.179.135

首先配置基础环境
主VIP上配置keepalive安装步骤如上，nginx安装步骤（略）
#keepalive主配置文件（如上单实例）
! Configuration File for keepalived

global_defs {
   notification_email {
   493939840@qq.com
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.179.2
   smtp_connect_timeout 30
   router_id LVS_7
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 55
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.179.110/24
    }

#nginx配置文件
[root@oldboy conf]# cat nginx.conf
worker_processes  1;
events {
    worker_connections  1024;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
    
upstream backend {
         server 192.168.179.134:80  weight=5;
         server 192.168.179.135:80   weight=5;
}
    server {
        listen       80;
        server_name  www.etiantian.org;
        index  index.html index.htm;
        location / {
        proxy_pass http://backend;
          }
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }
}

#备IP节点keeplivend配置文件

! Configuration File for keepalived
global_defs {
   notification_email {
   49000448@qq.com
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.179.2
   smtp_connect_timeout 30
   router_id LVS_2
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 55
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.179.110
    }
}

#备节点nginx配置文件
[root@oldboy conf]# vim /application/nginx/conf/nginx.conf

worker_processes  1;
events {
    worker_connections  1024;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
upstream backend {
         server 192.168.179.134:80  weight=5;
         server 192.168.179.135:80   weight=5;
}
    server {
        listen       80;
        server_name  www.etiantian.org;
        index  index.html index.htm;
        location / {
        proxy_pass http://backend;
          }
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }
}

#各自重启服务
/etc/init.d/keepalived restart
/application/nginx/sbin/nginx -s reload 
#在局域网的一台机器上测试
[root@oldboy conf]# curl 192.168.179.110
www.etiantian.org
[root@oldboy conf]# curl 192.168.179.110
http://www.etiantian.org
[root@oldboy conf]# curl 192.168.179.110
www.etiantian.org
[root@oldboy conf]# curl 192.168.179.110
http://www.etiantian.org

#主VIP110
[root@oldboy conf]# /etc/init.d/keepalived start
Starting keepalived:                                       [  OK  ]
[root@oldboy conf]# 
#备节点
[root@oldboy conf]# curl 192.168.179.110
www.etiantian.org
[root@oldboy conf]# curl 192.168.179.110
http://www.etiantian.org
[root@oldboy conf]# curl 192.168.179.110
www.etiantian.org
[root@oldboy conf]# curl 192.168.179.110
http://www.etiantian.org
[root@oldboy conf]# curl 192.168.179.110
www.etiantian.org
[root@oldboy conf]# curl 192.168.179.110
http://www.etiantian.org
#测试过程中发现，当主keepalived停止服务，nginx代理停止服务，它会自动切换到nginx备上 。如果是nginx代理先停止服务，它不会主动切换到备上 。
#如果nginx需要高可用前边还需要LVS IP负载均衡
#生产场景：
大并发 简单4层转发用lvs+keepalive，大并发，功能要求URL转发 LVS+nginx ，并发不大直接nginx或者haproxy，大公司，三个场景基本都会用