LVS+keepalived（DR）

時間 2019-11-17

標籤 lvs+keepalived lvs keepalived 欄目負載均衡简体版

原文原文鏈接

1、LVS+Keepalived 介紹

l LVS是Linux Virtual Server的簡寫，意即Linux虛擬服務器，是一個虛擬的服務器集羣系統。本項目在1998年5月由章文嵩博士成立，是中國國內最先出現的自由軟件項目之一。 html

l 目前有三種IP負載均衡技術（VS/NAT、VS/TUN和VS/DR）； linux

十種調度算法（rrr|wrr|lc|wlc|lblc|lblcr|dh|sh|sed|nq）。 web

l Keepalived在這裏主要用做RealServer的健康狀態檢查以及LoadBalance主機和BackUP主機之間failover的實現算法

l 在DR 模式的集羣中,LVS 負載調度器做爲羣集的訪問入口，但不做爲網關使用，服務池中全部節點都各自接入Internet，發送給客戶機的web響應數據包不須要通過lvs負載調度器。 vim

2、實驗環境與目標

網站負載均衡集羣拓撲圖

系統環境（配置好yum源）： bash

[root@host1 ~]# cat /etc/redhat-release 服務器

CentOS release 6.2 (Final) 網絡

[root@host1 ~]# uname -a 負載均衡

Linux localhost.localdomain 2.6.32-220.el6.x86_64 #1 SMP Tue Dec 6 19:48:22 GMT 2011 x86_64 x86_64 x86_64 GNU/Linux dom

經過部署Apache應用構建Web服務器測試效果，經過部屬iSCSI作爲存儲服務器。

實驗目標：

實現Web服務器的備份和冗餘，其中任意借點出現故障都會自動切

換，保證應用正常運行。

3、LVS調度器的配置

[root@host1 ~]# modprobe ip_vs

[root@host1 ~]# cat /proc/net/ip_vs

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

-> RemoteAddress:Port Forward Weight ActiveConn InActConn

[root@host1 ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth0:0

DEVICE=eth0:0

ONBOOT=yes

BOOTPROTO=static

IPADDR=192.168.10.100

NETMASK=255.255.255.0

[root@host1 ~]# /etc/init.d/network restart

[root@host1 ~]# ifconfig eth0:0

eth0:0 Link encap:Ethernet HWaddr 00:0C:29:46:D9:DE

inet addr:192.168.10.100 Bcast:192.168.10.255 Mask:255.255.255.0

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

[root@host1 ~]# vim /etc/sysctl.conf #避免網絡內的ARP解析出現異常，應該關閉Linux內核的重定向參數響應

#在最後添加

net.ipv4.conf.all.send_redirects = 0

net.ipv4.conf.default.send_redirects = 0

net.ipv4.conf.eth0.send_redirects = 0

[root@host1 ~]# sysctl -p

[root@host1 ~]# yum -y install ipvsadm #ipvsadm是負載調度器上使用LVS羣集管理工具，經過調用ip_vs模塊來添加、刪除服務器節點，以及查看羣集的運行狀態

[root@host1 ~]# ipvsadm -v

ipvsadm v1.25 2008/5/15 (compiled with popt and IPVS v1.2.1)

[root@host1 ~]# mkdir /etc/sysconfig/ipvsadm

[root@host1 ~]# /etc/init.d/ipvsadm restart

[root@host1 ~]# chkconfig ipvsadm on

[root@host1 ~]# yum -y install gcc kernel-devel openssl-devel popt-devel #安裝支持庫

[root@host1 ~]# tar -zxf keepalived-1.2.2.tar.gz

[root@host1 ~]# cd keepalived-1.2.2

[root@host1 ~]# vi keepalived/libipvs-2.6/ip_vs.h

將#include <sys/types.h>放到#include <linux/types.h>的上面

[root@host1 keepalived-1.2.2]# ./configure --prefix=/ --with-kernel-dir=/usr/src/kernels/2.6.18-194.el5-i686/

[root@host1 keepalived-1.2.2]# make

[root@host1 keepalived-1.2.2]# make install

[root@host1 keepalived-1.2.2]# chkconfig --add keepalived

[root@host1 keepalived-1.2.2]# chkconfig keepalived on

[root@host1 keepalived-1.2.2]# cd /etc/keepalived/

[root@host1 keepalived]# cp keepalived.conf keepalived.conf.bak

[root@host1 keepalived]# vim keepalived.conf #文件裏面全部內容

! Configuration File for keepalived

global_defs {

router_id LVS_MASTER #從調度器上改成router_id LVS_SLAVE

}

vrrp_instance VI_1 {

state MASTER #從調度器上改成state SLAVE

interface eth0

virtual_router_id 51

priority 100 #從調度器上改成priority 80

advert_int 1

authentication {

auth_type PASS

auth_pass 1111

}

virtual_ipaddress {

192.168.10.100

}

virtual_server 192.168.10.100 80 {

delay_loop 6

lb_algo rr

lb_kind DR

nat_make 255.255.255.0

persistence_timeout 50

protocol TCP

real_server 192.168.10.3 80 {

weight 1

TCP_CHECK {

connect_port 80

connect_timeout 3

nb_get_retry 3

}

real_server 192.168.10.4 80 {

weight 1

TCP_CHECK {

connect_port 80

connect_timeout 3

nb_get_retry 3

}

配置負載分配策略

# /etc/init.d/ipvsadm stop

# ipvsadm –A –t 192.168.10.100:80 –s rr

# ipvsadm –a –t 192.168.10.100:80 –r 192.168.10.3 –g –w 1

# ipvsadm –a –t 192.168.10.100:80 –r 192.168.10.4 –g –w 1

# /etc/init.d/ipvsadm save

# chkconfig ipvsadm on

ipvsadm

從調度器上同上全部配置，先安裝相關軟件包，在安裝keepalived，最後配置/etc/keepalived.conf,只需將註釋的地方修改便可

4、節點配置

（1）分別在2臺RealServer(節點)上面編寫腳本

[root@host3 ~]# vim /etc/init.d/realserver.sh

#!/bin/bash

VIP=192.168.10.100

startrs()

{

echo "start LVS of REALServer"

/sbin/ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up

/sbin/route add -host $VIP dev lo:0

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

}

stoprs()

{

/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

}

# ============ Main ===========

case $1 in

"start")

startrs;;

"stop")

stoprs;;

"*")

echo "Usage $0 {start|stop}"

exit 1

esac

[root@host3 ~]# chmod +x /etc/init.d/realserver.sh

[root@host3 ~]#/etc/init.d/realserver.sh start

(2)在2臺RealServer(節點)中分別配置HTTP並啓動realserver.sh

[root@host3 ~]# yum -y install httpd

[root@host3 ~]# cd /var/www/html/

[root@host3 html]# echo "192.168.10.3" > index.html

[root@host3 html]# cat index.html

192.168.10.3

[root@host4 html]# cat index.html #兩臺節點的配置除了網頁不同（爲了更明顯的看到測試效果），其餘都同樣

192.168.10.4

[root@host3 ~]# /etc/init.d/realserver.sh start

[root@host3 ~]# echo "/etc/init.d/realserver.sh start" >> /etc/rc.local

[root@host3 html]# /etc/init.d/httpd start

[root@host3 html]# chkconfig httpd on

(3)給2臺節點添加一條路由記錄，將訪問VIP的數據限制在本地以免通訊紊亂

[root@host4 ~]# route add -host 192.168.10.100 dev lo:0

[root@host4 ~]# echo "/sbin/route add -host 192.168.10.100 dev lo:0" >> /etc/rc.local

另外一臺的配置過程同樣，過程略

5、測試

在兩臺調度器上分別啓動Keepalived

[root@host1 ~]# /etc/init.d/keepalived restart

[root@host1 ~]# ipvsadm -Ln

IP Virtual Server version 1.2.1 (size=4096)

Prot LocalAddress:Port Scheduler Flags

-> RemoteAddress:Port Forward Weight ActiveConn InActConn

TCP 192.168.10.100:80 rr persistent 50

-> 192.168.10.3:80 Route 1 0 0

-> 192.168.10.4:80 Route 1 0 0

使用客戶機訪問<http://192.168.10.100>,使主調度器掛掉看是否可以訪問

使用客戶機訪問<http://192.168.10.100>,使一個節點掛掉看是否可以訪問

相關標籤/搜索

keepalived+dr

lvs+dr

dr+keepalived

heartbeat+ldirectord+dr

yanlz+steamvr+5g+ai+vr+ar+mr+hr+br+cr+dr+er+fr+gr

負載均衡

每日一句

每一个你不满意的现在，都有一个你没有努力的曾经。