LVS使用整理(1)

開始安裝LVS

1）下載相關軟件包

mkdir -p /home/tools/ cd /home/tools/ wget http://www.linuxvirtualserver.org/software/kernel-26/ipadm-1.26.tar.gz

2）安裝LVS命令

lsmod |grep ip_vs cat /etc/redhat-release uname -r ln -s /usr/src/kernels/2.6.18- /usr/src/linux 特別注意： 1）此ln命令的路徑要和uname -r 輸出結果內核版本對應。 2）若是沒有/usr/src/kernels/2.6,是由於缺乏kernel-devel-2.6.18軟件包。可經過yum install kernel-devel -y 安裝。 3）ln這個命令也能夠不執行，直接指定內核參數編譯。 tar zxvf ipvsadm-1.26.tar.gz make make install lsmod |grep ip_vs 提示： 1.此時ipvs模塊沒有被加載，能夠執行ipvsadm命令就會吧ip_vs加載到系統內核或執行命令modprobe ip_vs也能夠把ip_vs模塊加載到內核。而後再執行lsmod -l |grep ip_vs 應該看見ip_vs模塊被列出。 須要安裝依賴包 yum install libnl* popt* -y.

 

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負載均衡器配置

 

配置別名網卡

ifconfig eth0:1 192.168.1.181 netmask 255.255.255.0 up #<=別名的方式

④ 手工執行配置添加LVS服務器並增長兩臺RS

ipvsadm -C ipvsadm --set 30  5 60 ipvsadm -A -t 192.168.1.181:80 -s wrr -p 20 ipvsadm -a -t 192.168.1.181:80 -r 192.168.1.178:80 -g -w 1 ipvsadm -a -t 192.168.1.181:80 -r 192.168.1.179:80 -g -w 1

[刪除方法]

ipvsadm -D -t 192.168.1.181:80 -s wrr ipvsadm -d -t 192.168.1.181:80 -r 192.168.1.178:80

[相關參數說明]

ipvsadm -help --clear  -C  clear the whole table --add-service -A add virtual service with options --tcp-service -t service-address service-address is host[:port] --scheduler -s   scheduler  one of rr|wrr|lc|wlc|lblc|lblcr|dh|sh|sed|nq --add-server -a add real server with options --real-server -r server-address server-addres s is host(and port) --masquerading -m masquerading (NAT) --gatewaying -g gatewaying(direct routing)(default) --delete-server -d delete real server --persistent -p [timeout]   persistent server(會話保持功能） --set tcp tcpfin udp       set connection timeout values --weight  -w weight  capacity of real server 提示：更多參數請ipvsadm -help自行查看

⑤命令執行過程及檢查配置的執行結果

ipvsadm -C ipvsadm --set 30  5 60 ipvsadm -A -t 192.168.1.181:80 -s wrr -p 20 ipvsadm -a -t 192.168.1.181:80 -r 192.168.1.178:80 -g -w 1 ipvsadm -a -t 192.168.1.181:80 -r 192.168.1.179:80 -g -w 1 ipvsadm -L -n --sort ipvsadm -d -t 192.168.1.181:80 -r 192.168.1.178:80 ipvsadm -L -n --sort ipvsadm -a -t 192.168.1.181:80 -r 192.168.1.178:80 ipvsadm -L -n --sort

 

手工在RS端綁定VIP

ifconfig lo:181.168.1.181 netmask 255.255.255.255 up route add -host 192.168.1.181 dev lo

 每一個集羣節點的迴環接口（lo）設備上被綁定VIP地址（其廣播地址是其自己，子網掩碼255.255.255.255，採起可變掩碼方式把網段劃分紅只含一個主機地址的目的是避免ip地址衝突）容許LVS-DR集羣中的集羣節點接收發向該VIP地址的數據包，這會有一個很是嚴重的問題發生，集羣內部的真實服務器將嘗試回覆來自正在請求VIP客戶端的ARP廣播，這樣全部的真實服務器都將聲稱本身擁有該VIP地址，這時客戶端將直接發送請求數據包到真實服務器上，從而破壞DR集羣的方法。所以，必需要抑制真實服務器的ARP廣播。

手工在RS端抑制ARP響應

⑦抑制ARP響應方法以下：

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

以RS179爲例演示執行過程以下：

ifconfig lo:181 192.168.1.181 netmask 255.255.255.255 up route add -host 192.168.1.181 dev lo cat /proc/sys/net/ipv4/conf/lo/arp_ignore cat /proc/sys/net/ipv4/conf/all/arp_ignore cat /proc/sys/net/ipv4/conf/all/arp_ignore cat /proc/sys/net/ipv4/conf/lo/arp_announce 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

 

arp音質技術參數說明

arp_ignore- INTEGER

0 默認值：

 

檢查手工配置成果

使用http://192.168.1.178{179}(181)

使用腳本配置LVS負載均衡服務器端

#!/bin/bash . /etc/init.d/functions VIP=192.168.1.181 SUBNET=eth0:`echo $VIP|cut -d. -f4` PORT=80 GW=192.168.1.1 #w=3 RIP1=(         192.168.1.178      ) #w=1 RIP2=(         192.168.1.179      ) IFCONFIG=/sbin/ifconfig ROUTE=/sbin/route IPVSADM=/sbin/ipvsadm ARPING=/sbin/arping #functions function usage (){         local script_name         script_name=$1         echo "Usgae : $script_name [ start | stop | restart ]"         echo ""         return 1 } function checkCmd (){         if [ ! -f $1 ]; then                 echo "Can't find "$1                 return 1         fi } function checkSubnet (){         $IFCONFIG |grep "$1"|wc -l } function ipvsStart (){         #judge if $SUBNET is exist.         if [ $(checkSubnet $SUBNET) -ne 0 ]; then                 $IFCONFIG $SUBNET down         fi         local rs         #$IFCONFIG $SUBNET $VIP broadcast $VIP netmask 255.255.255.255 up         $IFCONFIG $SUBNET $VIP broadcast $VIP netmask 255.255.255.0 up         #$ROUTE add -host $VIP dev $SUBNET         $IPVSADM -C         $IPVSADM -A -t $VIP:$PORT -s wrr -p 60         for ((i=0; i<`echo ${#RIP1[*]}`; i++))         do                 $IPVSADM -a -t $VIP:$PORT -r ${RIP1[$i]}:$PORT -g -w 1         done         for ((i=0; i<`echo ${#RIP2[*]}`; i++))         do                 $IPVSADM -a -t $VIP:$PORT -r ${RIP2[$i]}:$PORT -g -w 1         done         rs=$?         $IPVSADM >/tmp/oldboy.log         # update MAC      NetIf=$(echo ${SUBNET}|awk -F ":" '{print $1}')         $ARPING -c 1 -I ${NetIf} -s $VIP $GW >>/tmp/oldboy.log         [ $rs -eq 0 ] && action "Ipvsadm start." /bin/true         return $rs } function ipvsStop (){         local rs      rs=1         #clean ipvs      $IFCONFIG $SUBNET down         $IPVSADM -C         $IPVSADM -Z                 rs=$?         #$ROUTE del $VIP      $ARPING -c 1 -I ${NetIf} -s $VIP $GW  >/dev/null 2>&1         [ $rs -eq 0 ] && action "Ipvsadm stoped." /bin/true         return $rs } main () {      #judge argv num by oldboy         if [ $# -ne 1 ]; then                 usage $0         fi         case "$1" in                 start)                         ipvsStart                         ;;                 stop)                         ipvsStop                         ;;                 restart)                         ipvsStop                         ipvsStart                         ;;                 *)                         usage $0                         ;;         esac } #start operating main $*

開發腳本配置LVS RS真實服務器處理腳本

#!/bin/bash # description: Config realserver lo and apply noarp VIP=(         192.168.1.181      ) . /etc/rc.d/init.d/functions case "$1" in start)         for ((i=0; i<`echo ${#VIP[*]}`; i++))         do            interface="lo:`echo ${VIP[$i]}|awk -F . '{print $4}'`"            /sbin/ifconfig $interface ${VIP[$i]} broadcast ${VIP[$i]} netmask 255.255.255.255 up         done         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          action "Start LVS of RearServer.by old1boy"         ;; stop)         for ((i=0; i<`echo ${#VIP[*]}`; i++))         do             interface="lo:`echo ${VIP[$i]}|awk -F . '{print $4}'`"             /sbin/ifconfig $interface ${VIP[$i]} broadcast ${VIP[$i]} netmask 255.255.255.255 down         done         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          action "Close LVS of RearServer.by old2boy"         ;; *)         echo "Usage: $0 {start|stop}"         exit 1 esac

一個腳本同時實現自動剔除和加入RS

CURL方法很不錯 #!/bin/bash PORT="80"VIP=192.168.1.181RIP=(    192.168.1.178    192.168.1.179)function check_url(){for ((i=0; i<`echo ${#RIP[*]}`; i++))dojudge=($(curl -I -s http://${RIP[$i]}|head -1|tr "\r" "\n"))if [[ "${judge[1]}" == '200' && "${judge[2]}"=='OK' ]]   then     if [ `ipvsadm -L -n|grep "${RIP[$i]}"|wc -l` -ne 1 ]      then      ipvsadm -a -t $VIP:$PORT -r ${RIP[$i]}:$PORT     fielse      if [ `ipvsadm -L -n|grep "${RIP[$i]}"|wc -l` -eq 1 ]      then      ipvsadm -d -t $VIP:$PORT -r ${RIP[$i]}:$PORT     fifidone}while truedocheck_urlsleep 5done