Lvs + keepalived for load balancing and troubleshooting (DR Mode)

Http://antsw.blog.51cto.com/936097/214975 this article from the "mountain twist" blog

Node1: 192.168.1.253
Node2: 192.168.1.254
VIP: 192.168.1.250
 
Environment centos5.2 (I used two machines here)
1. Install ipvsadm
Yum-y install ipvsadm
 
2. Install keepalived
[Root @ node1 ~] # Wget http://www.keepalived.org/software/keepalived-1.1.15.tar.gz
[Root @ node1 ~] # Tar zxvf keepalived-1.1.15.tar.gz
[Root @ node1 ~] # Cd keepalived-1.1.15
[Root @ node1 keepalived-1.1.15] #. /configure -- prefix =/-- mandir =/usr/local/share/man/-- with-kernel-dir =/usr/src/kernels/2.6.18-92. el5-i686/
The result is entered correctly after configure.
Keepalived configuration
------------------------
Keepalived version: 1.1.15
Compiler: gcc
Compiler flags:-g-O2
Extra Lib:-lpopt-lssl-lcrypto
Use IPVS Framework: Yes # support for lvs
S sync daemon support: Yes
Use VRRP Framework: Yes
Use LinkWatch: No
Use Debug flags: No
 
[Root @ node1 keepalived-1.1.15] # make & make install
At this point, the installation of lvs + keepalived is complete. However, you cannot use the lvs function. Next, configure lvs + keepalived in dr mode.
 
3. [root @ node1 ~] # Cd/etc/keepalived/
[Root @ node1 keepalived] # vim keepalived. conf
! Configuration File for keepalived
Global_defs {
Notification_email {
Shanswei@gmail.com
}
Notification_email_from shanswei@gmail.com
Smtp_server 127.0.0.1
Smtp_connect_timeout 30
Router_id LVS_DEVEL
}
 
Vrrp_instance VI_1 {
State MASTER # Set master lvs to MASTER
Interface eth0
Virtual_router_id 51
Priority 102 # Set From lvs to 99
Advert_int 1
Authentication {
Auth_type PASS
Auth_pass 1111
}
Virtual_ipaddress {
192.168.1.250 # if multiple VIPs exist, enter the new line.
}
}
Virtual_server 192.168.1.250 80 {
Delay_loop 6
Lb_algo wlc
Lb_kind DR
Persistence_timeout 50
Protocol TCP
 
Real_server 192.168.1.253 80 {
Weight 3
TCP_CHECK {
Connect_port 80
Connect_timeout 30
}
}
Real_server 192.168.1.254 80 {
Weight 1
TCP_CHECK {
Connect_port 80
Connect_timeout 30
}
}
 
Now, the keepalived configuration is complete.
Start keepalived
[Root @ node1 ~] #/Etc/init. d/keepalived start
If you want to start with the system, run chkconfig -- add keepalived
Chkconfig keepalived on
 
4. Configure the Real Server. Use the script here (this script is only executed on the WEB machine. I use two machines now. Servers act as both lvs and web servers)
[Root @ node1 keepalived] # vim realserver
#! /Bin/bash
# Description: start realserver
VIP = 192.168.1.250
/Etc/rc. d/init. d/functions
Case "$1" in
Start)
Echo "start LVS of REALServer"
/Sbin/ifconfig lo: 0 $ VIP broadcast $ VIP netmask 255.255.255.255 up
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
;;
Stop)
/Sbin/ifconfig lo: 0 down
Echo "close LVS Directorserver"
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 "Usage: $0 {start | stop }"
Exit 1
Esac
[Root @ node1 keepalived] # chmod + x realserver
[Root @ node1 keepalived] #./realserver start
 
5. Start keepalived (with startup log)
[Root @ node1 ~] #/Etc/init. d/keepalived start (Master LVS)
Oct 15 13:59:36 vmtest Keepalived: Starting Keepalived v1.1.15 (10/15, 2009)
Oct 15 13:59:36 vmtest Keepalived_healthcheckers: Using MII-BMSR NIC polling thread...
Oct 15 13:59:36 vmtest Keepalived_healthcheckers: Netlink reflector reports IP 192.168.1.253 added
Oct 15 13:59:36 vmtest Keepalived_healthcheckers: Netlink reflector reports IP 10.0.0.253 added
Oct 13:59:36 vmtest Keepalived_healthcheckers: Registering Kernel netlink reflector
Oct 13:59:36 vmtest Keepalived_healthcheckers: Registering Kernel netlink command channel
Oct 13:59:36 vmtest Keepalived_healthcheckers: Opening file/etc/keepalived. conf.
Oct 13:59:36 vmtest Keepalived_healthcheckers: Configuration is using: 11891 Bytes
Oct 13:59:36 vmtest Keepalived_healthcheckers: Activating healtchecker for service [192.168.1.253: 80]
Oct 13:59:36 vmtest Keepalived_healthcheckers: Activating healtchecker for service [192.168.1.254: 80]
Oct 15 13:59:36 vmtest Keepalived: Starting Healthcheck child process, pid = 28419
Oct 15 13:59:36 vmtest Keepalived_vrrp: Using MII-BMSR NIC polling thread...
Oct 15 13:59:36 vmtest Keepalived_vrrp: Netlink reflector reports IP 192.168.1.253 added
Oct 15 13:59:36 vmtest Keepalived: Starting VRRP child process, pid = 28420
Oct 13:59:36 vmtest Keepalived_vrrp: Netlink reflector reports IP 10.0.0.253 added
Oct 13:59:36 vmtest Keepalived_vrrp: Registering Kernel netlink reflector
Oct 13:59:36 vmtest Keepalived_vrrp: Registering Kernel netlink command channel
Oct 13:59:36 vmtest Keepalived_vrrp: Registering gratutious ARP shared channel
Oct 13:59:36 vmtest Keepalived_vrrp: Opening file/etc/keepalived. conf.
Oct 13:59:36 vmtest Keepalived_vrrp: Configuration is using: 36278 Bytes
Oct 15 13:59:36 vmtest Keepalived_vrrp: VRRP sockpool: [ifindex (2), proto (112), fd ()]
Oct 15 13:59:37 vmtest Keepalived_vrrp: VRRP_Instance (VI_1) Transition to MASTER STATE
Oct 13:59:38 vmtest Keepalived_vrrp: VRRP_Instance (VI_1) Entering MASTER STATE
Oct 13:59:38 vmtest Keepalived_vrrp: VRRP_Instance (VI_1) setting protocol VIPs.
Oct 13:59:38 vmtest Keepalived_vrrp: VRRP_Instance (VI_1) Sending gratuitous ARPs on eth0 for 192.168.1.250
Oct 13:59:38 vmtest Keepalived_healthcheckers: Netl