LVS+keeplived

关于安装，选择的系统是CentOS5.4，Keepalived的版本是1.2.1。也试用centos5.5+keepalived1.2.2，但是没成功，由于刚刚接触，还有经验深入troubleshooting。

1.先安装LVS

系统光盘中有rpm包（ipvsadm-1.24-10.i386.rpm ），也可以使用yum安装。

2. 安装keepalived，

     a. 下载源码，wget http://www.keepalived.org/software/keepalived-1.2.1.tar.gz

     b. 解压缩，

      c, 编译时，需要使用内核代码，先执行如下命令

              ln -s /usr/src/kernels/2.6.18-164.el5-i686/ /usr/src/linux

           否则，编译后，Use IPVS Framework 和IPVS sync daemon support 是No。

           或者使用参数

./configure –prefix=/usr/local/keepalived –with-kernel-dir=/usr/src/kernels/2.6.18-164.el5-x86_64/

 

Keepalived configuration
------------------------
Keepalived version       : 1.2.1
Compiler                 : gcc
Compiler flags           : -g -O2 -DETHERTYPE_IPV6=0x86dd
Extra Lib                : -lpopt -lssl -lcrypto
Use IPVS Framework       : No
IPVS sync daemon support : No
Use VRRP Framework       : Yes
Use Debug flags          : No

3. 安装

   #  ./configure --prefix=/usr/local/keepalived
   #  make
   #  make install

4. 复制文件到相应系统对应目录

   #  cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/
   #  cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
   #  mkdir /etc/keepalived
   #  cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
   #  cp /usr/local/keepalived/sbin/keepalived /usr/sbin/

5. 配置keepalived，使用NAT模式

编辑/usr/local/keepalived/etc/keepalived/keepalived.conf，此配置使用NAT模式，完成后copy到/etc/keepalived/, 因为默认使用这个目录的配置文件。

 

! Configuration File for keepalived


global_defs {
   notification_email {
     [email protected]
     [email protected]
   }
   notification_email_from [email protected]
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_MASTER
}

vrrp_sync_group VG1 {
   group {
      VI_1
      VI_GATEWAY
   }
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
     lvs_sync_daemon_inteface eth0
    virtual_router_id 51
    priority 100
    advert_int 1
     smtp_alert
    authentication {
        auth_type PASS
        auth_pass example
    }
    virtual_ipaddress {
        10.130.193.251
    }
}

vrrp_instance VI_GATEWAY {
        state BACKUP
        interface eth1
        lvs_sync_daemon_inteface eth1
        virtual_router_id 52
        priority 100
        advert_int 1
        smtp_alert
        authentication {
                auth_type PASS
                auth_pass example
        }
        virtual_ipaddress {
                172.20.8.254
        }
}

virtual_server 10.130.193.251 80 {
    delay_loop 6
    lb_algo rr
    lb_kind NAT
    nat_mask 255.255.255.0
    persistence_timeout 1800
    protocol TCP

    real_server 172.20.8.237 80 {
        weight 1
        TCP_CHECK {
        connect_timeout 10
         nb_get_retry 3
         delay_before_retry 3
         connect_port 80
     }
    }
}

 

6. 启动keepalived

由于使用NAT模式，需要IP转发，执行如下命令。

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

#/etc/rc.d/init.d/keepalived start

6.1设置开机启动

# vi /etc/rc.d/rc.local

#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.

touch /var/lock/subsys/local
echo 1 > /proc/sys/net/ipv4/ip_forward

#chkconfig keepalived on

 6.2设置默认启动参数

默认启动参数是-D，修改/etc/sysconfig/keepalived来设置默认启动参数。

# --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 -d -S 0"

 

7. 查看log

使用参数启动keepalived，然后再查看/var/log/messages

#/usr/local/keepalived/sbin/keepalived -d -D

Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: VRRP_Instance(VI_1) Received higher prio advert
Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: VRRP_Instance(VI_1) Entering BACKUP STATE
Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: VRRP_Instance(VI_1) removing protocol VIPs.
Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: VRRP_Group(VG1) Syncing instances to BACKUP state
Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: VRRP_Instance(VI_GATEWAY) Entering BACKUP STATE
Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: VRRP_Instance(VI_GATEWAY) removing protocol VIPs.
Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: Remote SMTP server [10.130.170.57:25] connected.
Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: Netlink reflector reports IP 10.130.171.252 removed
Mar  3 15:35:56 VSHcentos5 Keepalived_vrrp: Netlink reflector reports IP 192.168.158.132 removed
 

8. 查看转发和连接

  #  ipvsadm 
  #  ipvsadm -lcn

9. 在LVS的主机上启用NAT，可使real server主动访问非子网的资源

# iptables -t nat -A POSTROUTING -s 172.20.8.0/24 -o eth0 -j SNAT --to 10.130.193.231
# /etc/rc.d/init.d/iptables save