centos搭建keepalived+ipvsadm實現高可用lvs分發

標籤：centos keepalived lvs realserver

這文檔適合非常簡單的不需要任何技術完全照著弄的擁有三台以上機器的情況。

虛ip192.168.200.16

keepalived主192.168.98.11

keepalived備192.168.98.98

realserver一192.168.99.131

realserver二192.168.98.11或192.168.98.98（當11存活時候，就是11當rs，死了就98當rs）

1、keepalived主192.168.98.11進行如下安裝配置。

yum install -y wget ipvsadm vim

wget http://www.keepalived.org/software/keepalived-1.2.24.tar.gz

tar xf keepalived-1.2.24.tar.gz 

cd keepalived-1.2.24

./configure --prefix=/usr/local/keepalived

make && make install

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

cd /usr/local/keepalived/etc/keepalived/

ln -s /usr/local/keepalived/sbin/keepalived /usr/sbin/

chkconfig --add keepalived

chkconfig keepalived on

vim /etc/keepalived/keepalived.conf 粘貼下面的。

vrrp_instance ha44 {

    state MASTER

    interface eth0

    virtual_router_id 51

    priority 100

#advert_int廣播間隔，這值影響master掛多久切換到backup，我實測設定2或者3的話切換間隔較短

    advert_int 2

    authentication {

        auth_type PASS

        auth_pass 1234

    }

    virtual_ipaddress {

        192.168.200.16

#可以自訂掩碼、廣播。

#        192.168.200.16/16 brd 192.168.255.255 dev eth0

    }

#可以自訂網關,不過我沒這麼用過。

#    virtual_routes {

#        192.168.200.0/16 via 192.168.98.1 dev eth0

#    }

}

#如果想用lvs的功能，就添加以下內容，keepalived會自動調用ipvsadm功能。

virtual_server 192.168.200.16 80 {

    delay_loop 3

    lb_algo rr

    lb_kind DR

    persistence_timeout 50

    protocol TCP

    real_server 192.168.98.11 80 {

        weight 20

        TCP_CHECK

        {

            connect_timeout 3

            nb_get_retry 3

            delay_before_retry 3

        }

    }

    real_server 192.168.99.131 80 {

        weight 100

        TCP_CHECK

        {

            connect_timeout 3

            nb_get_retry 3

            delay_before_retry 3

        }

    }

}

儲存退出

/etc/init.d/keepalived start

2、keepalived備192.168.98.98進行如下安裝配置。

yum install -y wget ipvsadm vim

wget http://www.keepalived.org/software/keepalived-1.2.24.tar.gz

tar xf keepalived-1.2.24.tar.gz 

cd keepalived-1.2.24

./configure --prefix=/usr/local/keepalived

make && make install

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

cd /usr/local/keepalived/etc/keepalived/

ln -s /usr/local/keepalived/sbin/keepalived /usr/sbin/

chkconfig --add keepalived

vim /etc/keepalived/keepalived.conf 粘貼下面的。

vrrp_instance ha44 {

    state BACKUP

    interface eth0

    virtual_router_id 51

    priority 20

#advert_int廣播間隔，這值影響master掛多久切換到backup，我實測設定2或者3的話切換間隔較短

    advert_int 2

    authentication {

        auth_type PASS

        auth_pass 1234

    }

     virtual_ipaddress {

        192.168.200.16

#可以自訂掩碼、廣播。

#        192.168.200.16/16 brd 192.168.255.255 dev eth0

    }

#可以自訂網關，不過我沒這麼用過。

#    virtual_routes {

#        192.168.200.0/16 via 192.168.98.1 dev eth0

#    }

}

#如果想用lvs的功能，就添加以下內容，keepalived會自動調用ipvsadm功能。

virtual_server 192.168.200.16 80 {

    delay_loop 3

    lb_algo rr

    lb_kind DR

    persistence_timeout 50

    protocol TCP

    real_server 192.168.98.98 80 {

        weight 20

        TCP_CHECK

        {

            connect_timeout 3

            nb_get_retry 3

            delay_before_retry 3

        }

    }

    real_server 192.168.99.131 80 {

        weight 100

        TCP_CHECK

        {

            connect_timeout 3

            nb_get_retry 3

            delay_before_retry 3

        }

    }

}

儲存退出

service keepalived start

3、realserver一192.168.99.131的配置。

yum install -y vim

vim /etc/init.d/lvsrs 粘貼如下內容。

#!/bin/sh

#chkconfig:345 61 61

#description:LVSRS

VIP=192.168.200.16

Usage ()

{

echo "Usage:`basename $0` (start|stop)"

exit 1

}

if [ $# -ne 1 ];then

Usage

fi

case $1 in

start)

echo "configuring vip for Real Server"

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

echo "1" >/proc/sys/net/ipv4/conf/eth0/arp_ignore

echo "2" >/proc/sys/net/ipv4/conf/eth0/arp_announce

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

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

if [ $? -eq 0 ]

then

sleep 5

echo "Real Server started."

else

echo "error occurred!"

fi

;;

stop)

/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

echo "0" >/proc/sys/net/ipv4/conf/eth0/arp_ignore

echo "0" >/proc/sys/net/ipv4/conf/eth0/arp_announce

if [ $? -eq 0 ]

then

sleep 2

echo "Real Server has stopped."

else

echo ‘error occurred occurred! Maybe "lo:0" has stopped already.‘

fi

;;

*)

Usage

esac

儲存退出

chmod +x /etc/init.d/lvsrs

chkconfig --add lvsrs

service lvsrs start

4、realserver二192.168.98.11或192.168.98.98，這倆由於已經配置了keepalived，由keepalived服務代管ipvsadm，所以它倆不需要再配置啥就已經自然成為了realserver了。

備忘：

1、以上配置用於這仨機器都提供http服務的情況。

2、如果多台keepalived伺服器需要提供更多服務，就複製添加更多virtual_server並修改連接埠即可。如果不配置virtual_server部分，keepalived就不代管lvs了，那麼同一時刻只有一台機器工作而已，這台出了問題，vip才會飄到下一台上。vip在哪台，就是哪台工作，所以通常，lvs和keepalived是配合使用的，是需要配置virtual_server部分的。

3、若配置多個vrrp_instance，每個instance需要擁有獨一無二的virtual_router_id，與其他instance相同是不行的。多台機器啟動keepalived服務後，就是以virtual_router_id的值來進行配對兒的。

4、keepalived設定檔中的priority優先順序的設定大有玄機！設定的不科學就會事與願違！建議查看一下相關資料兒瞭解了以後再設定。 戳這兒就有一篇哦

centos搭建keepalived+ipvsadm實現高可用lvs分發