通過keepalived搭建LVS高可用集羣
實驗環境:
主Director Server 192.168.163.3
備Director Server 192.168.163.4
real server1 192.168.163.5
real server2 192.168.163.6
VIP 192.168.163.100
四個節點上都安裝上webserver:
#yum -y install httpd
在Director上安裝好LVS軟件和keepalived軟件
LVS下載地址:http://www.linuxvirtualserver.org/software/ipvs.html
keepalived官網:http://www.keepalived.org
1.源碼安裝:
安裝LVS
#tar -zxvf ipvsadm-1.24.tar.gz #cd ipvsadm-1.24 #make #make install
安裝keepalived
#tar -zxvf keepalived-1.1.19.tar.gz #cd keepalived-1.1.19 #./configure --sysconf=/etc --with-kerner-dir=/usr/src/kernels/2.6.18-8.el5-i686 #make #make install
2.yum源安裝:
#yum -y install ipvsadm #yum -y install keepalived
編輯keepalived的配置文件(/etc/keepalived/keepalived.conf)主要由3部分組成,分別爲全局定義,vrrp實例定義,虛擬服務器定義
#全局定義 global_defs { #設置報警郵件地址,可以多個,每行一個 notification_email { root@localhost } #設置郵件發送地址 notification_email_from keepalived@localhost #設置smtp server地址 smtp_server 127.0.0.1 #設置smtp server連接超時時間 smtp_connect_timeout 30 #表示運行keepalived服務器的一個標識 router_id LVS_DEVEL } #完成keepalived的手動切換 vrrp_script chk_schedown { script "[[ -f /etc/keepalived/down ]] && exit 1 || exit 0" interval 2 weight -2 } #vrrp實例定義 vrrp_instance VI_1 { state MASTER #定義keepalived角色,備節點爲BACKUP interface eth0 #指定HA監測的網絡接口 virtual_router_id 51 #虛擬路由標識,主備要一致 priority 100 #優先級,數字越大優先級越高,備節點小於主節點 advert_int 1 #主備節點同步檢查時間間隔,單位爲秒 authentication { auth_type PASS #設置認證類型,主要由PASS和AH auth_pass keepalivedpass #設置認證密碼,同一個實例下,主備節點要一致 } virtual_ipaddress { #虛擬IP,可以多個,每行一個 192.168.163.100/24 dev eth0 label eth0:0 } track_script { #要執行的腳本 chk_schedown } } #虛擬服務器定義 virtual_server 192.168.163.100 80 { #定義虛擬服務器IP和PROT delay_loop 6 #設置運行狀況檢查時間,單位爲秒 lb_algo rr #設置負載均衡調度算法 lb_kind DR #設置LVS實現負載均衡的機制,有NAT,DR,TU # persistence_timeout 50 #會話保持時間,單位爲秒 protocol TCP #指定轉發協議類型 sorry_server 127.0.0.1 80 #定義所有realserver均出現故障時所用的服務器 real_server 192.168.163.5 80 { #定義real server的IP和端口 weight 1 #定義權重 HTTP_GET { #real server的狀態檢測,還有TCP_CHECK等 url { #檢查的URL地址和應返回的狀態碼 path / status_code 200 } connect_timeout 3 #設置連接超時時間 nb_get_retry 3 #設置重試次數 delay_before_retry 3 #設置重試間隔 } } real_server 192.168.163.6 80 { weight 1 HTTP_GET { url { path / status_code 200 } connect_timeout 3 nb_get_retry 3 delay_before_retry 3 } } }
在real server上編寫腳本完成VIP設置和節點的配置(/etc/init.d/lvsrs)
#!/bin/bash # # Script to start LVS DR real server. # chkconfig: - 90 10 # description: LVS DR real server # . /etc/rc.d/init.d/functions VIP=192.168.163.100 host=`/bin/hostname` case "$1" in start) # Start LVS-DR real server on this machine. /sbin/ifconfig lo down /sbin/ifconfig lo 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 /sbin/ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up /sbin/route add -host $VIP dev lo:0 ;; stop) # Stop LVS-DR real server loopback device(s). /sbin/ifconfig lo:0 down 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 ;; status) # Status of LVS-DR real server. islothere=`/sbin/ifconfig lo:0 | grep $VIP` isrothere=`netstat -rn | grep "lo:0" | grep $VIP` if [ ! "$islothere" -o ! "isrothere" ];then # Either the route or the lo:0 device # not found. echo "LVS-DR real server Stopped." else echo "LVS-DR real server Running." fi ;; *) # Invalid entry. echo "$0: Usage: $0 {start|status|stop}" exit 1 ;; esac
啓動keepalived+LVS集羣系統
在主備Director server上啓動keepalived服務
#service keepalived start
在兩個real server上啓動real server的配置腳本
#service lvsrs start
在四個節點啓動httpd服務
#service httpd start