一、keepalive+LVS（DR）
最少需要4台服务器
两台LVS调度器、两台真实服务器
两台LVS调度器上安装keepalive，形成热备份
（一）配置LVS调度器
1.安装相关依赖包和编译环境
yum -y install gcc gcc-c++
yum -y install kernel-devel openssl-devel popt-devel ipvsadm*
2.安装keepalive
（1）查看内核版本
[[email protected] ~]# uname -a
Linux sutang 2.6.32-431.el6.x86_64 #1 SMP Fri Nov 22 03:15:09 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
（2）解压
[[email protected] ~]# tar zxf keepalived-2.0.15.tar.gz
（3）编译安装
[[email protected] keepalived-2.0.15]# ./configure --prefix=/usr/local/keepalived --with-dir=/usr/src/kernels/2.6.32-431.el6.x86_64/
此处内核目录的名和uname参看的参数。
make && make install
（4）拷贝配置文件
mkdir /etc/keepalived
cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
（5）加入启动项
拷贝安装目录中的相关文件
cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
拷贝执行相关文件
cp /usr/local/keepalived/sbin/* /usr/sbin/
解压目录中复制启动脚本文件
[[email protected] keepalived-2.0.15]# cp keepalived/etc/init.d/keepalived /etc/init.d/
添加执行权限
chmod +x /etc/init.d/keepalived
加入启动项
chkconfig --add keepalived
chkconfig keepalived on
3.修改配置文件
（1）主LVS调度器的配置文件修改
备份：
cd /etc/keepalived/
cp keepalived.conf keepalived.conf.bak
修改配置文件
vim /etc/keepalived/keepalived.conf
修改结果内容如下：
! Configuration File for keepalived
global_defs {
#运行keepalive的机器标识，同一网段唯一
router_id sutang-116
}
vrrp_instance VI_1 {
# 设置为master节点
state MASTER
# 虚拟ip绑定的网卡名称
interface eth0
# 同一个keepalived组，节点的设置必须一样，这样才会被识别
virtual_router_id 116
# 节点的权重，备份节点值要比master节点低
priority 100
advert_int 1
# 认证方式设置
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
# 绑定虚拟ip到网卡
192.168.88.110
}
}
virtual_server 192.168.88.110 80 {
#设置运行情况检查时间，单位是秒
delay_loop 6
#负载算法，这里是rr表示轮询
lb_algo rr
#定义模式，这里是Direct route
lb_kind DR
#会话保存时长(秒)，0表示不使用stickyness会话
persistence_timeout 0
#设置采用tcp服务
protocol TCP
#以下为真实服务器的相关设置
real_server 192.168.88.113 80 {
weight 1
#以下表示采用http模式检查该服务器监控状态
HTTP_GET {
url {
#检测的网页路径
path /index.html
}
#连接超时时间，秒
connect_timeout 3
#重试次数
nb_get_retry 3
#每次重试前等待延迟时间
delay_before_retry 3
}
}
#另一台真实服务器的相关设置
real_server 192.168.88.114 80 {
weight 1
HTTP_GET {
url {
path /index.html
}
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
}
（2）备LVS调度器的配置文件修改
备份：
cd /etc/keepalived/
cp keepalived.conf keepalived.conf.bak
修改配置文件
vim /etc/keepalived/keepalived.conf
修改结果内容如下：
! Configuration File for keepalived
global_defs {
router_id sutang-115
}
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 116
priority 50
advert_int 1
# 认证方式设置
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.88.110
}
}
virtual_server 192.168.88.110 80 {
delay_loop 6
lb_algo rr
lb_kind DR
persistence_timeout 0
protocol TCP
real_server 192.168.88.113 80 {
weight 1
HTTP_GET {
url {
path /index.html
}
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
real_server 192.168.88.114 80 {
weight 1
HTTP_GET {
url {
path /index.html
}
connect_timeout 3
nb_get_retry 3
delay_before_retry 3
}
}
}
（二）配置真实服务器
此处采用httpd当真实服务器
1.安装httpd
yum -y install httpd
2.关闭响应ARP请求
vim /etc/sysctl.conf
在文件末尾添加如下内容：
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.default.arp_ignore = 1
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
修改并生效
sysctl -p
3. 配置群集端口
ifconfig lo:0 192.168.88.110 broadcast 192.168.88.110 netmask 255.255.255.255 up
此为临时配置，重启network失效。
其中的IP为虚拟服务器的IP。
4. 添加群集路由
route add -host 192.168.88.110 lo:0
5.分别在两台真实服务器添加测试页
echo "114" > /var/www/html/index.html
echo "113" > /var/www/html/index.html
6.启动httpd服务
service httpd start
（三）测试
1.测试准备
两台LVS调度器：
开启keepalive（service keepalived start）
两台真实服务器：
开启httpd（service httpd start）
所有主机：
关闭防火墙（service iptables stop）、关闭selinux（setenforce 0）
2.浏览器访问
刷新一下：
3.查看LVS上的记录
（1）主LVS调度器：
漂移IP记录
[[email protected] ~]# ip a
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:c1:10:77 brd ff:ff:ff:ff:ff:ff
inet 192.168.88.116/24 brd 192.168.88.255 scope global eth0
inet 192.168.88.110/32 scope global eth0
inet6 fe80::20c:29ff:fec1:1077/64 scope link
valid_lft forever preferred_lft forever
[[email protected] ~]#
查看虚拟服务器列表
[[email protected] ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.88.110:80 rr
-> 192.168.88.113:80 Route 1 0 0
-> 192.168.88.114:80 Route 1 0 0
[[email protected] ~]#
查看连接情况：
[[email protected] ~]# ipvsadm -Lnc
IPVS connection entries
pro expire state source virtual destination
TCP 01:57 FIN_WAIT 192.168.88.8:58120 192.168.88.110:80 192.168.88.113:80
TCP 01:56 FIN_WAIT 192.168.88.8:58119 192.168.88.110:80 192.168.88.114:80
TCP 01:56 FIN_WAIT 192.168.88.8:58118 192.168.88.110:80 192.168.88.113:80
TCP 01:55 FIN_WAIT 192.168.88.8:58117 192.168.88.110:80 192.168.88.114:80
[[email protected] ~]#
（2）备LVS调度器
查看漂移IP记录
[[email protected] ~]# ip a
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:dc:ab:70 brd ff:ff:ff:ff:ff:ff
inet 192.168.88.115/24 brd 192.168.88.255 scope global eth0
inet6 fe80::20c:29ff:fedc:ab70/64 scope link
valid_lft forever preferred_lft forever
[[email protected] ~]#
由于是备份所以没有抢到漂移IP。
查看虚拟服务器列表
[[email protected] ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.88.110:80 rr
-> 192.168.88.113:80 Route 1 0 0
-> 192.168.88.114:80 Route 1 0 0
[[email protected] ~]#
查看连接情况
[[email protected] ~]# ipvsadm -Lnc
IPVS connection entries
pro expire state source virtual destination
[[email protected] ~]#
由于该主机是备份所以没有记录。
（3）关闭主LVS
关闭主LVS调度器后查看备份LVS调度器的情况：
查看漂移IP：
[[email protected] ~]# ip a
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:dc:ab:70 brd ff:ff:ff:ff:ff:ff
inet 192.168.88.115/24 brd 192.168.88.255 scope global eth0
inet 192.168.88.110/32 scope global eth0
inet6 fe80::20c:29ff:fedc:ab70/64 scope link
valid_lft forever preferred_lft forever
[[email protected] ~]#
刷新几下浏览器页面，然后查看连接记录
[[email protected] ~]# ipvsadm -Lnc
IPVS connection entries
pro expire state source virtual destination
TCP 01:49 FIN_WAIT 192.168.88.8:58148 192.168.88.110:80 192.168.88.114:80
TCP 01:50 FIN_WAIT 192.168.88.8:58150 192.168.88.110:80 192.168.88.114:80
TCP 01:49 FIN_WAIT 192.168.88.8:58149 192.168.88.110:80 192.168.88.113:80
TCP 01:50 FIN_WAIT 192.168.88.8:58151 192.168.88.110:80 192.168.88.113:80
[[email protected] ~]#