实验环境---ubuntu16.04
四台机器：10.211.55.13—55.16
-
具体实验环境配置如下：
10.211.55.102 LVS_VIP
10.211.55.13 LVS_MASTER
10.211.55.14 LVS_SALVE
10.211.55.15 WEB1
10.211.55.16 WEB2
安装LVS与Keepalived
sudo apt install ipvsadm
打开ip forward功能：文件/etc/sysctl.conf
打开后修改里面“net.ipv4.ip_forward = 1”
执行如下命令使设置生效：
sudo sysctl -p
sudo apt install ipvsadm
打开ip forward功能：文件/etc/sysctl.conf
打开后修改里面“net.ipv4.ip_forward = 1”
执行如下命令使设置生效：
sysctl -p
接下来开启keepalived服务：LVS MASTER. LVS SLAVE都要操作如下：55.13 55.14
sudo systemctl start keepalived.service
查看keepalived进程：
[root@lvs keepalived-1.2.7]# sudo ps aux|grep keepalived
root 18485 0.0 0.0 42164 972 ? Ss 11:43 0:00 keepalived -D
root 18486 0.0 0.2 46464 2376 ? S 11:43 0:00 keepalived -D
root 18487 0.0 0.1 46340 1740 ? S 11:43 0:00 keepalived -D
去master查看虚拟ip是否加上：注意如果虚拟ip没有自动加上，请重启下keepalived服务。虚拟ip :55.102(自定义)
parallels@parallels-vm:~$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: enp0s5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:1c:42:41:65:f6 brd ff:ff:ff:ff:ff:ff
inet 10.211.55.13/24 brd 10.211.55.255 scope global dynamic enp0s5
valid_lft 1117sec preferred_lft 1117sec
inet 10.211.55.102/32 scope global enp0s5
valid_lft forever preferred_lft forever
inet6 fdb2:2c26:f4e4:0:2d91:9984:fe45:63ca/64 scope global temporary dynamic
valid_lft 602038sec preferred_lft 83527sec
inet6 fdb2:2c26:f4e4:0:e00e:d6:1c91:3bea/64 scope global mngtmpaddr noprefixroute dynamic
valid_lft 2591853sec preferred_lft 604653sec
inet6 fe80::5806:a54:e63b:90c0/64 scope link
valid_lft forever preferred_lft forever
上述显示55.102虚拟ip加上了！
接下里配置部署两台web服务器:
配置部署10.211.55.15 web1:
配置虚拟IP启动脚本:
parallels@parallels-vm:~$ pwd
/home/parallels
parallels@parallels-vm:~$ cat realserver.sh
#Written by :NetSeek http://www.linuxtone.org
VIP=10.211.55.102
. /lib/init/vars.sh
. /lib/lsb/init-functions
case "$1" in
start)
ifconfig lo:0 $VIP netmask 255.255.255.255 broadcast $VIP
/sbin/route add -host $VIP dev lo:0
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
sysctl -p >/dev/null 2>&1
echo "RealServer Start OK"
;;
stop)
ifconfig lo:0 down
route del $VIP >/dev/null 2>&1
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 "RealServer Stoped"
;;
*)
echo "Usage: $0 {start|stop}"
exit 1
esac
exit 0
配置部署tomcat：
sudo apt-get install tomcat7 -y
启动tomcat服务：
sudo systemctl start tomcat7.service
为了测试负载均衡，我们将这个页面改下，以更好的标识这个网页是本服务器的
Tomcat7安装目录位于/usr/share/tomcat7，所以我们要编辑tomcat下的webapps/ROOT/index.html这个文件。
parallels@parallels-vm:/usr/share/tomcat7-root/default_root$ pwd
/usr/share/tomcat7-root/default_root
删掉此目录的index.html文件：sudo rm -f index.html
重新创建此目录的index.html文件，内容如下：
Sudo touch /usr/share/tomcat7-root/default_root/index.html
parallels@parallels-vm:/usr/share/tomcat7-root/default_root$ cat index.html
web1 10.211.55.15
启动虚拟IP的脚本：
sudo sh realserver.sh start
去LVS_MASTER服务器的终端查看下ipvsadm，查看WEB1(55.15)服务器加到集群里:
sudo ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 10.211.55.102:8080 rr persistent 50
-> 10.211.55.15:8080 Route 1 0 0
上述可见：55.15已经加进来了！
此时我们访问网页http://10.211.55.15:8080，出现界面显示web1 10.211.55.15；或者使用命令行测试转发情况都可以查看。
配置部署10.211.55.16 web2:
配置虚拟IP启动脚本:
parallels@parallels-vm:~$ pwd
/home/parallels
parallels@parallels-vm:~$ cat realserver.sh
#Written by :NetSeek http://www.linuxtone.org
VIP=10.211.55.102
. /lib/init/vars.sh
. /lib/lsb/init-functions
case "$1" in
start)
ifconfig lo:0 $VIP netmask 255.255.255.255 broadcast $VIP
/sbin/route add -host $VIP dev lo:0
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
sysctl -p >/dev/null 2>&1
echo "RealServer Start OK"
;;
stop)
ifconfig lo:0 down
route del $VIP >/dev/null 2>&1
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 "RealServer Stoped"
;;
*)
echo "Usage: $0 {start|stop}"
exit 1
esac
exit 0
配置部署tomcat：
sudo apt-get install tomcat7 -y
启动tomcat服务：
sudo systemctl start tomcat7.service
为了测试负载均衡，我们将这个页面改下，以更好的标识这个网页是本服务器的
Tomcat7安装目录位于/usr/share/tomcat7，所以我们要编辑tomcat下的webapps/ROOT/index.html这个文件。
parallels@parallels-vm:/usr/share/tomcat7-root/default_root$ pwd
/usr/share/tomcat7-root/default_root
删掉此目录的index.html文件：sudo rm -f index.html
重新创建此目录的index.html文件，内容如下：
Sudo touch /usr/share/tomcat7-root/default_root/index.html
parallels@parallels-vm:/usr/share/tomcat7-root/default_root$ cat index.html
Web2 10.211.55.16
启动虚拟IP的脚本：
sudo sh realserver.sh start
去LVS_MASTER服务器的终端查看下ipvsadm，查看WEB2服务器加到集群里:
sudo ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 10.211.55.102:8080 rr persistent 50
-> 10.211.55.15:8080 Route 1 0 0
-> 10.211.55.16:8080 Route 1 0 0
上述55.15 55.16两台web都已经加进来了
最后客户端测试：
浏览器输入：vip地址即10.211.55.102:8080
停掉其中一台keepalived，服务正常访问!