Linux运维之DR模式下的高可用LVS

高可用的作用

高可用是资源池中的某些物理主机出现故障后，故障物理主机上的虚拟机会在资源池内其他正常的物理主机上启动，从而保障资源池安全可靠的持续运行，是服务器虚拟化软件的常见功能

搭建步骤

本次实验用四个虚拟机,分别为server1,server2,server3,server4,server1作为主调度器,server4作为辅助调度器,当主调度器故障后辅助调度会代替工作

1.server1:配置yum源

vim /etc/yum.repos.d/rhel-source.repo 
  1 [rhel-source]
  2 name=Red Hat Enterprise Linux $releasever - $basearch - Source
  3 baseurl=http://172.25.61.250/rhel6.5
  4 enabled=1
  5 gpgcheck=1
  6 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release
  7 
  8 [LoadBalancer]
  9 name=LoadBalancer
 10 baseurl=http://172.25.61.250/rhel6.5/LoadBalancer
 11 gpgcheck=0
 12 
 13 [HighAvailability]
 14 name=HighAvailability
 15 baseurl=http://172.25.61.250/rhel6.5/HighAvailability
 16 gpgcheck=0

2.在主调度器上安装源码包keepalived-2.0.6

解压 :tar zxf keepalived-2.0.6.tar.gz

3.安装编译所需软件

 yum install -y gcc libnl libnl-devel
 yum install -y openssl-devel

 yum install -y libnfnetlink-devel-1.0.0-1.el6.x86_64.rpm 

4.进入解压好的目录下,编译,安装

cd keepalived-2.0.6
./configure --prefix=/usr/local/keepalive --with-init=SYSV
make && make install

看到 Use IPVS Framework 为yes就算编译安装完成

5.将主调度器上编译完成的keeplived发给辅助rs一份

scp /usr/local/keepalived/ server4:/usr/local

6.给予可执行权限,制作软链接

chmod +x  /usr/local/keepalived/etc/rc.d/init.d/keepalived 
    5  ln -s /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
    6  ln -s /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
    7   ln -s /usr/local/keepalived/etc/keepalived/ /etc/
    8   ln -s /usr/local/keepalived/sbin/keepalived /sbin/

辅助rs相同的步骤

7.安装调度器

yum install ipvsadm -y

编写主rs的keepalived主配置文件

vim /etc/keepalived/keepalived.conf 

  3 global_defs {
  4    notification_email {
  5      root@localhost
  6    }
  7    notification_email_from [email protected]
  8    smtp_server 127.0.0.1
  9    smtp_connect_timeout 30
 10    router_id LVS_DEVEL
 11    vrrp_skip_check_adv_addr
 12    #vrrp_strict
 13    vrrp_garp_interval 0
 14    vrrp_gna_interval 0
 15 }
 16 
 17 vrrp_instance VI_1 {
 18     state MASTER
 19     interface eth0
 20     virtual_router_id 51
 21     priority 100
 22     advert_int 1
 23     authentication {
 24         auth_type PASS
 25         auth_pass 1111
 26     }
 27     virtual_ipaddress {
 28         172.25.61.100
 29     }
 30 }
 31 
 32 virtual_server 172.25.61.100 80 {
 33     delay_loop 3
 34     lb_algo rr
 35     lb_kind DR
 36    #persistence_timeout 50
 37     protocol TCP
 38 
 39     real_server 172.25.61.2 80 {
 40         TCP_CHECK{
 41         weight 1
 42             connect_timeout 3
 43             retry 3
 44             delay_before_retry 3
 45         }
 46     }
 47 
 48     real_server 172.25.61.3 80 {
 49         TCP_CHECK{
 50         weight 1
 51             connect_timeout 3
 52             retry 3
 53             delay_before_retry 3
 54         }
 55     }
 56 }

备用调度器上配置文件要将MASTER改为BACKUP,priority权重系数改为50

8.server2和server3的apache服务开启

9.server1和server4(即主调度器和辅助调度器)的服务打开

/etc/init.d/keepalived start

10.测试

在真机上测试

发现server2和server3轮循调度

[root@foundation61 ~]# curl 172.25.61.100
LVS server3
[root@foundation61 ~]# curl 172.25.61.100
LVS server2
[root@foundation61 ~]# curl 172.25.61.100
LVS server3
[root@foundation61 ~]# curl 172.25.61.100
LVS server2

将主调度器上把keepalived服务停掉,在测试发现server2和server3仍然轮循,但ip已经漂移到副调度器上

[root@foundation61 ~]# curl 172.25.61.100
LVS server3
[root@foundation61 ~]# curl 172.25.61.100
LVS server2
[root@foundation61 ~]# curl 172.25.61.100
LVS server3
[root@foundation61 ~]# curl 172.25.61.100
LVS server2

[root@server4 ~]# ip a
1: lo:  mtu 16436 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0:  mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:3f:af:58 brd ff:ff:ff:ff:ff:ff
    inet 172.25.61.4/24 brd 172.25.61.255 scope global eth0
    inet 172.25.61.100/32 scope global eth0
    inet6 fe80::5054:ff:fe3f:af58/64 scope link 
       valid_lft forever preferred_lft forever