Keepalived + LVS/DR 安装配置

Keepalived + LVS/DR

说明

• Keepalived：可以踢出掉故障服务
• Keepalived：可以实现主从切换，解决单点故障

实验环境

• 四台主机：Linux Centos 6.4 32位
• 两台Director：LVS+Keepalived
• 两台Web：Apache

环境搭建操作

web server 端

1、添加虚拟IP脚本

vim /usr/local/sbin/lvs_dr.sh

#/bin/bash
vip=192.168.1.100
# 把vip绑定在lo上，是为了实现rs直接把结果返回给客户端
ifconfig lo:0 $vip broadcast $vip netmask 255.255.255.255 up
route add -host $vip lo:0
# 以下操作为更改arp内核参数，目的是为了让rs顺利发送mac地址给客户端
echo "">/proc/sys/net/ipv4/conf/lo/arp_ignore
echo "">/proc/sys/net/ipv4/conf/lo/arp_announce
echo "">/proc/sys/net/ipv4/conf/all/arp_ignore
echo "">/proc/sys/net/ipv4/conf/all/arp_announce
# 更改内核配置文件之后生效命令，可以不加 sysctl -a 查看所有内核参数
# sysctl -p

脚本文件

2、执行脚本

sh /usr/local/sbin/lvs_dr.sh

主 Director

1、安装服务

yum -y install keepalived.i686 0:1.2.7-3.el6
yum -y install ipvsadm.i686

2、开启路由转发功能

echo 1 > /proc/sys/net/ipv4/ip_forward

3、配置Keepalived配置文件

vim /etc/keepalived/keepalived.conf

! Configuration File for keepalived

vrrp_instance VI_1 {
    # 备用服务器上为 BACKUP
    state MASTER
    # 公网的网卡
    interface eth0
    # 自定义id数值
    virtual_router_id 51
    # 权重值、主要高于slave
    priority 100
    # 检测服务器状态间隔时间
    advert_int 1
    authentication {
        # 密码类型
        auth_type PASS
        # 密码
        auth_pass 1111
    }
    virtual_ipaddress {
        # 虚拟IP地址，可以为多个
        192.168.1.100
    }
}

# 配置VIP
virtual_server 192.168.1.100 80 {
    # 每隔6秒查询realserver状态
    delay_loop 6
    # LVS算法
    lb_algo wlc
    # Direct Route
    lb_kind DR
    # 同一个IP的链接0秒内被分配到同一台realserver
    persistence_timeout 0
    # 用TCP协议检查realserver状态
    protocol TCP

    # 配置realserver
    real_server 192.168.1.111 80 {
        # 权重
        weight 100
        TCP_CHECK {
        # 10秒无响应超时
        connect_timeout 10
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }

    # 配置realserver
    real_server 192.168.1.115 80 {
        # 权重
        weight 100
        # 检测
        TCP_CHECK {
        # 10秒无响应超时
        connect_timeout 10
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }
}

主配置文件

4、启动服务：先启动主后启动从

/etc/init.d/keepalived start

从 Director

1、安装服务

yum -y install keepalived.i686 0:1.2.7-3.el6
yum -y install ipvsadm.i686

2、开启路由转发功能

echo 1 > /proc/sys/net/ipv4/ip_forward

3、配置Keepalived配置文件

vim /etc/keepalived/keepalived.conf

! Configuration File for keepalived

vrrp_instance VI_1 {
    # 主用服务器上为 MASTER
    state BACKUP
    # 公网的网卡
    interface eth0
    # 自定义id数值
    virtual_router_id 51
    # 权重值、主要高于slave
    priority 90
    # 检测服务器状态间隔时间
    advert_int 1
    authentication {
        # 密码类型
        auth_type PASS
        # 密码
        auth_pass 1111
    }
    virtual_ipaddress {
        # 虚拟IP地址，可以为多个
        192.168.1.100
    }
}

# 配置VIP
virtual_server 192.168.1.100 80 {
    # 每隔6秒查询realserver状态
    delay_loop 6
    # LVS算法
    lb_algo wlc
    # Direct Route
    lb_kind DR
    # 同一个IP的链接0秒内被分配到同一台realserver
    persistence_timeout 0
    # 用TCP协议检查realserver状态
    protocol TCP

    # 配置realserver
    real_server 192.168.1.111 80 {
        # 权重
        weight 100
        TCP_CHECK {
        # 10秒无响应超时
        connect_timeout 10
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }

    # 配置realserver
    real_server 192.168.1.115 80 {
        # 权重
        weight 100
        # 检测
        TCP_CHECK {
        # 10秒无响应超时
        connect_timeout 10
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }
}

主配置文件

4、启动服务：先启动主后启动从

/etc/init.d/keepalived start

查询状态

命令：ipvsadm -l

IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.1.100:http wlc
  -> 192.168.1.111:http           Route   100    0          0
  -> 192.168.1.115:http           Route   100    0          0         

主：查看LVS状态

命令：ip addr

2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:67:0e:20 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.160/24 brd 192.168.1.255 scope global eth0
    inet 192.168.1.100/32 scope global eth0
    inet6 fe80::20c:29ff:fe67:e20/64 scope link
       valid_lft forever preferred_lft forever

主：查看VIP

命令：ipvsadm -l

IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.1.100:http wlc
  -> 192.168.1.111:http           Route   100    0          0
  -> 192.168.1.115:http           Route   100    0          0         

从：查看LVS状态

命令：ip addr

2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:9e:70:1e brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.161/24 brd 192.168.1.255 scope global eth0
    inet6 fe80::20c:29ff:fe9e:701e/64 scope link
       valid_lft forever preferred_lft forever

从：查看VIP

命令：ifconfig

lo:0      Link encap:Local Loopback
          inet addr:192.168.1.100  Mask:255.255.255.255
          UP LOOPBACK RUNNING  MTU:16436  Metric:1

web端：查看VIP

测试

http://192.168.1.100/
LVS 1
http://192.168.1.100/
LVS 2
http://192.168.1.100/
LVS 1
http://192.168.1.100/
LVS 2

测试负载均衡

#---------------------------单点故障-------------------------------#

Dir 主 端：ifdown eth0 关闭网卡

# 查看IP飘逸192.168.1.100
Dir 从端：ip addr
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:9e:70:1e brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.161/24 brd 192.168.1.255 scope global eth0
    inet 192.168.1.100/32 scope global eth0
    inet6 fe80::20c:29ff:fe9e:701e/64 scope link
       valid_lft forever preferred_lft forever

# 查看日志
主端：tail -f /var/log/messages
Dec 24 02:36:18 localhost Keepalived_healthcheckers[1916]: Netlink reflector reports IP 192.168.1.100 added

#------------------------------------------------------------------#

#---------------------------恢复单点故障-----------------------------#

Dir 主 端：ifup eth0 启动网卡

# 查看IP飘逸192.168.1.100
Dir 主 端： ip addr
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:67:0e:20 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.160/24 brd 192.168.1.255 scope global eth0
    inet 192.168.1.100/32 scope global eth0
    inet6 fe80::20c:29ff:fe67:e20/64 scope link
       valid_lft forever preferred_lft forever

# 查看日志
Dir 从 端： tail -f /var/log/messages
Dec 24 02:36:23 localhost Keepalived_vrrp[1917]: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.1.100
Dec 24 02:48:02 localhost Keepalived_vrrp[1917]: VRRP_Instance(VI_1) Received higher prio advert
Dec 24 02:48:02 localhost Keepalived_vrrp[1917]: VRRP_Instance(VI_1) Entering BACKUP STATE
Dec 24 02:48:02 localhost Keepalived_vrrp[1917]: VRRP_Instance(VI_1) removing protocol VIPs.
Dec 24 02:48:02 localhost Keepalived_healthcheckers[1916]: Netlink reflector reports IP 192.168.1.100 removed

#------------------------------------------------------------------#

测试 单点故障 IP飘逸