LVS+keeplived

posir

　　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 {
  
•      ginosun@xxx.com
  
•      gino@126.com
  
•    }
  
•    notification_email_from keepalived@xxx.com
  
•    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