搭建lvs + keepalived 伺服器
環境： linux redhat 7.2
四臺主機劃分
LVS 1:10.6.248.196
LVS 2:10.6.248.197
MYSQL MASTER:10.6.248.198
MYSQL MASTER:10.6.248.199
VIP:10.6.248.192

其中問題：
1，兩臺LVS爭奪VIP
原因：Keepalived 配置檔案中的 ID 號在同一個IP地址段中，被其他Keepalived的使用。
2，無法繫結VIP
VIP 地址被佔用，更換VIP 地址

一，安裝及配置mysql 主主

二，安裝keepalived + lvs

 1，先安裝所需軟體包

執行命令：
#yum install -y kernel-devel openssl openssl-devel gcc* popt-devel ncurses* bison* ipvsadm httpd perl* libart* rrdtool* c* gc* libnl*

 2，確認核心支援 ipvs

執行命令：
#modprobe -l | grep ipvs
#lsmod | grep ip_vs
作業系統中7.2版本下，我只能用#lsmod | grep ip_vs 具體原因沒有細究

 3，可以通過YUM 安裝ipvsadm(lvs)
 

執行命令：
#yum -y install ipvsadm
或者
#wget http://www.linuxvirtualserver.org/software/kernel-2.6/ipvsadm-1.26.tar.gz

 4，通過執行ipvsadm 命令來檢驗是否安裝成功

執行命令：
#ipvsadm
引數一般使用 -Ln 或者-ln

 5，安裝keepalived

執行命令：
#wget http://www.keepalived.org/software/keepalived-1.2.13.tar.gz
#tar -zxvf keepalived-1.2.13.tar.gz
#cd keepalived-1.2.13
#make && make install
#./configure --prefix=/usr/local/keepalived --with-kernel-dir=/usr/src/kernels/2.6.32-431.5.1.el6.x86_64/
建立目錄並進行配置：
# mkdir /etc/keepalived

     #cp /usr/local/keepalived/etc/rc.d/init.d/keepalived  /etc/rc.d/init.d/​

     #cp /usr/local/keepalived/etc/sysconfig/keepalived  /etc/sysconfig/​

     #cp /usr/local/keepalived/etc/keepalived/keepalived.conf  /etc/keepalived/

​ #cp /usr/local/keepalived/sbin/keepalived /usr/sbin/

​ #chkconfig keepalived on
修改keepalived配置檔案

執行命令：
#vim /etc/keepalived/keepalived.conf
內如如下

! Configuration File for keepalived

global_defs {
notification_email {
[email protected]
[email protected]
[email protected]
}
notification_email_from [email protected]
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}

vrrp_instance VI_1 {
state MASTER 備庫修改為BACKUP
interface eno16777984
virtual_router_id 123 備庫ID 一樣
priority 130 備庫優先順序要設定降低 130一下
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
10.6.248.192 虛擬IP
}
}

virtual_server 10.6.248.192 3306 { 虛擬IP
delay_loop 6
lb_algo rr 策略
lb_kind DR 策略
nat_mask 255.255.255.0
persistence_timeout 50
protocol TCP

real_server 10.6.248.199 3306 {                  受虛擬IP 監控的地址
    weight 1                                     權重
    SSL_GET {
        connect_timeout 3
        nb_get_retry 3
        delay_before_retry 3
    }
}


real_server 10.6.248.198 3306 {
    weight 1
    SSL_GET {
        connect_timeout 3
        nb_get_retry 3
        delay_before_retry 3
    }
}

}

keepalived 的配置檔案預設為搶奪模式，
在vrrp_instance VI_1下面增加一個nopreempt 引數，設定為非搶奪模式。
但是HA的非搶奪模式時將master 和 backup的state都設定backup ，讓其通過priority來競爭。

Keepalived LVS2上面也需要如此配置

配置LVS （此指令碼需要新增到LVS1,MYSQL-MASTER-1,MYSQL-MASTER-2）上。
mysql-master1 及mysql-master2上如果沒有此指令碼，那麼在應用端通過mysql客戶端連線的時候，是無法進入mysql資料庫的。

執行命令：
#vim /etc/init.d/realserver.sh

內容如下：
指令碼一：

#!/bin/bash
#description: Config realserver

VIP=10.6.248.192

/etc/rc.d/init.d/functions

case “$1” in
start)
/sbin/ifconfig lo:0 $VIP netmask 255.255.255.255 broadcast $VIP
/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
sysctl -p >/dev/null 2>&1
echo “RealServer Start OK”
;;
stop)
/sbin/ifconfig lo:0 down
/sbin/route del $VIP >/dev/null 2>&1
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 “RealServer Stoped”
;;
*)
echo “Usage: $0 {start|stop}”
exit 1
esac

exit 0

指令碼二： （僅用與參考，網上有）

#!/bin/bash
#description: Config realserver
VIP=10.6.248.170
/etc/rc.d/init.d/functions
case “$1” in
start)
/sbin/ifconfig lo down
/sbin/ifconfig lo up
ifconfig lo:0 $VIP netmask 255.255.255.255 broadcast $VIP
/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
sysctl -p >/dev/null 2>&1
echo “RealServer Start OK”
;;
stop)
ifconfig lo:0 down
route del KaTeX parse error: Expected 'EOF', got '&' at position 18: …P >/dev/null 2>&̲1 echo "…VIP"isRoOn=/bin/netstat -rn | grep “ $VIP"` if [ "$isLoON” == “” -a “$isRoOn” == “” ]; then
echo “LVS-DR real server has run yet.”
else
echo “LVS-DR real server is running.”
fi
exit 3
;;
*)
echo “Usage: $0 {start|status|stop}”
exit 1
esac
exit 0

將LVS 指令碼加入開機自啟動
執行如下命令：
#chmod +x /etc/init.d/realserver
#echo “/etc/init.d/realserver” >> /etc/rc.d/rc.local
分別啟動lVS 和 keepalived
執行如下命令：
# service realserver start / sh /etc/init.d/realserver.sh start
# service keepalived start

在mysql 主主的伺服器上 執行

          # service realserver start   /  sh /etc/init.d/realserver.sh start

LVS + keepalived 配置到此結束

linux 環境配置
執行命令：
#vim /etc/hosts
127.0.0.1 Kmaster localhost.localdomain localhost4 localhost4.localdomain4
::1 Kmaster localhost.localdomain localhost6 localhost6.localdomain6
10.6.248.199 Mymaster
10.6.248.198 Myslave
10.6.248.197 Monitor
10.6.248.196 Kmaster
#10.6.248.170 VIP

          #vim  /etc/sysctl.conf

net.ipv4.ip_local_port_range = 10000 65000
net.ipv4.ip_forward = 1
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.ip_nonlocal_bind = 1
#sysctl -p

測試如下：
1，#ipvsadm
顯示結果如下
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 10.6.248.192:mysql rr persistent 50
-> Myslave:mysql Route 1 0 0
-> Mymaster:mysql Route 1 0 0

2，ipvsadm -ln --stats 當有連線的時候，ActiveConn 以及 InActConn 會有變化

3，檢視keepalived 檢測狀態以及檢視 /var/log/messages的日誌
#service keepalived status

4，關閉Master 1 上的mysql 服務
檢視LVS1 上的日誌 vim /var/log/messages 可以發現已經Master 1 踢出
重啟Master 1 上的mysql 服務
可以發現Master 1已經加入
5，關閉LVS 1 上的 keepalived 的服務，會發現，VIP 已經轉移到 LVS 2上，且日誌中會有顯示，可以檢視LVS 2上的keepalived的狀態。

select host,user,authentication_string from mysql.user;

show grants for ‘repl’@‘10.6.248.%’
grant replication slave on . to ‘repl’@‘10.6.248.%’;

insert into mysql.user(host,user,authentication_string,ssl_cipher,x509_issuer,x509_subject) values (‘10.6.249.%’,‘rep1’,password(‘[email protected]’),’’,’’,’’);

update mysql.user set select_priv=‘y’, insert_priv=‘y’,update_priv=‘y’, Alter_priv=‘y’,delete_priv=‘y’,create_priv=‘y’,drop_priv=‘y’,reload_priv=‘y’,shutdown_priv=‘y’,Process_priv=‘y’,file_priv=‘y’,grant_priv=‘y’,References_priv=‘y’,index_priv=‘y’,create_user_priv=‘y’,show_db_priv=‘y’,super_priv=‘y’,create_tmp_table_priv=‘y’,Lock_tables_priv=‘y’,execute_priv=‘y’,repl_slave_priv=‘y’,repl_client_priv=‘y’,create_view_priv=‘y’,show_view_priv=‘y’,create_routine_priv=‘y’,alter_routine_priv=‘y’,create_user_priv=‘y’ where host=‘10.6.249.%’ and user=‘rep1’;