RHEL6.5 + Keepalived 实现双机热备
目录：
3.2 Master/slaver分别配置防火墙........................................................................ 3
3.3 配置RHEL6.5本地镜像yum源........................................................................... 4
3.3.1 为本地镜像创建挂载目录......................................................................... 4
3.3.2 挂载DVD至本地新建目录......................................................................... 4
3.3.3 备份yum源配置文件................................................................................ 4
3.3.4 修改yum源配置文件................................................................................ 4
3.3.5 清除旧的缓存数据................................................................................... 5
3.3.6 配置本地yum源完成................................................................................ 5
6.1 在本机上查看虚拟ip状态................................................................................ 8
6.2 在同一网段的其他机器上查询arp缓存............................................................. 9
6.3 停掉master的master网络/keepalived........................................................... 9
6.4 重启master网络/keepalived服务................................................................. 10
7.1 （master/slave）分别安装http服务：......................................................... 11
7.3 Master正常情况访问测试............................................................................... 11
7.4 Master宕机或者keepalived服务异常............................................................ 12
Keepalived实现双机热备
首先有一个虚拟ip暴露给客户端，虚拟ip对应的mac地址为一台真实服务器，即用户向虚拟ip发送一个请求，该请求会被分发到真实服务器上。
现在有2台真实服务器，一台master，一台backup，master和backup上都运行着keepalived，当master挂了的时候，backup检测之后，自己成为master,且arp缓存虚拟ip对应的mac地址将变为backup的mac地址，这样请求虚拟ip的报文会被发送到backup。
架构图如下：
主机：192.168.1.171
备机：192.168.1.172
虚拟ip：192.168.1.173
操作系统：RedHat Enterprise Linux 6.5 x86_64
操作系统安装过程网上安装文档较多，此过程省略。
分别在master和slaver主机写入
#vim /etc/hosts
192.168.1.171 rhelha01.site
192.168.1.172 rhelha02.site
关闭防火墙
#serviceiptables stop
#vim/etc/selinux/config
SELINUX=disabled
利用RHEL6.5操作系统光盘制作一个本地yum源，具体配置步骤如下：
#mkdir /media/mnt
#mount /dev/cdrom /media/mnt
#cp /etc/yum.repos.d/rhel-source.repo/etc/yum.repos.d/rhel-source.repo.backup
#vim /etc/yum.repos.d/rhel-source.repo
删除原有内容，添加如下：
[RHEL-Source]
name=local ios
baseurl=file:///media/mnt/
enabled=1
gpgcheck=0
gpgkey=file:///media/mnt/RPM-GPG-KEY-redhat-release
yum clean all
yum makecache
yum list
下载：keepalived-1.2.16.tar.gz
http://www.keepalived.org/download.html
# tar zxf keepalived-1.2.16.tar.gz
cd keepalived-1.2.16
#./configure --disable-fwmark--prefix=/usr/local/keepalived
#make && make install
mkdir/etc/keepalived/
cp/usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
cp/usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
cp /usr/local/keepalived/etc/sysconfig/keepalived/etc/sysconfig/
ln -s/usr/local/keepalived/sbin/keepalived /sbin/
vi /etc/keepalived/keepalived.conf
###############################################
Maste! Configuration File forkeepalived
global_defs {
notification_email {
acassen@firewall.loc
failover@firewall.loc
sysadmin@firewall.loc
}
notification_email_from Alexandre.Cassen@firewall.loc
smtp_server 192.168.200.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_typePASS
auth_pass1111
}
virtual_ipaddress {
192.168.1.173
}
}
######################################################
vi /etc/keepalived/keepalived.conf
Backup 和master一样，只要修改如下地方：
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 51
priority 99 # 这里改为99，master优先级是100
advert_int 1
authentication {
auth_typePASS
auth_pass1111
}
virtual_ipaddress {
192.168.1.173
}
}
停止
service keepalived stop
启动
service keepalived start
重启
service keepalived restart
查看状态
service keepalived status
ip add
#arp -a
这里的1.73对应的mac地址6a:c7（即master的MAC地址）。
6.3 停掉master的master网络/keepalived
#servicekeepalived stop
在同一网段的其他机器上查询arp缓存
#arp –a
发现1.173的mac地址已经变为5a:7c（即slave的mac地址）。
在同一网段的其他机器上，测试连接1.173，发现成功切换到ha02(1.172)主机。
# arp -a
这里的1.73重新对应的mac地址6a:c7（即master的MAC地址）。
在同一网段的其他机器上，测试连接1.173，发现成功切换到ha01(1.171)主机。
那么主备双机热备就完成了！
#cd/media/mnt/Packages/
#yum install -yhttpd*
#service httpdstart
#chkconfighttpd on
Master：
#echo"redhat-ha-master-server01">>/var/www/html/index.html
Slaver：
#echo"redhat-ha-master-server02">>/var/www/html/index.html
可以看到服务已经由redhat-ha-master-server01自动转换至redhat-ha-master-server02.
1.master主机挂了，或者master 上keepalived挂了之后，可以切换到slave
2.在主机宕机或断网后可能需要重启keepalived服务。
