在 LVS高可用(六)LVS+keepalived主从 篇中提到了LVS的高可用及后端的LB,不过一台LVS提供服务,另一台只做为backup,显然是种浪费,实际现网应用中比较多的用法是,两台LVS都作为MASTER节点,互相做为另一台的backup 。具体架构如下:
注:与master-backup 架构相比, master-master架构需要多加一个VIP地址。
一、IP及规划
realserver | 192.168.122.10 |
192.168.122.20 | |
director | 192.168.122.30 |
192.168.122.40 | |
VIP | 192.168.122.100 |
192.168.122.110 |
同上一篇,两台realserver还是安装httpd ,两台director安装ipvsadm、keepalived 。realserver的回环地址上会配置两个VIP的地址。
另外操作前,需要先将几台主机的时间同步掉。
二、director主机配置
MASTER HostA主机的配置如下:
[root@lvs-dr ~]# cat /etc/keepalived/keepalived.conf vrrp_instance bl_one { state MASTER #指定Keepalived的角色,MASTER为主服务器,BACKUP为备用服务器 interface eth0 #指定HA监测的接口 lvs_sync_daemon_interface eth0 virtual_router_id 38 #虚拟路由标识(1-255),在一个VRRP实例中主备服务器ID必须一样 priority 150 #优先级,数字越大越优先,主服务器优先级必须高于备服务器 advert_int 3 #设置主备之间同步检查时间间隔,单位秒 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { #定义虚拟IP地址 192.168.122.100 } } vrrp_instance bl_two { state BACKUP interface eth0 lvs_sync_daemon_interface eth0 virtual_router_id 48 priority 120 advert_int 3 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.122.110 } } virtual_server 192.168.122.100 80 { delay_loop 3 #设置健康状态检查时间 lb_algo rr #设置负载调度算法 lb_kind DR #设置LVS实现负载均衡的机制 persistence_timeout 50 #会话保持时间 protocol TCP real_server 192.168.122.10 80 { weight 1 TCP_CHECK { connect_timeout 10 #设置响应超时时间 nb_get_retry 3 #设置超时重试次数 delay_before_retry 3 #设置超时重试间隔 connect_port 80 } } real_server 192.168.122.20 80 { weight 1 TCP_CHECK { connect_timeout 10 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } } virtual_server 192.168.122.110 80 { delay_loop 3 lb_algo rr lb_kind DR persistence_timeout 50 protocol TCP real_server 192.168.122.10 80 { weight 1 HTTP_GET { url { path /index.html status_code 200 } connect_timeout 10 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } real_server 192.168.122.20 80 { weight 1 HTTP_GET { url { path /index.html status_code 200 } connect_timeout 10 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } }
MASTER HostB主机的配置如下:
[root@lvs-dr2 ~]# cat /etc/keepalived/keepalived.conf vrrp_instance bl_one { state BACKUP interface eth0 lvs_sync_daemon_interface eth0 virtual_router_id 38 priority 120 advert_int 3 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.122.100 } } vrrp_instance bl_two { state MASTER interface eth0 lvs_sync_daemon_interface eth0 virtual_router_id 48 priority 150 advert_int 3 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.122.110 } } virtual_server 192.168.122.100 80 { delay_loop 3 lb_algo rr lb_kind DR persistence_timeout 50 protocol TCP real_server 192.168.122.10 80 { weight 1 TCP_CHECK { connect_timeout 10 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } real_server 192.168.122.20 80 { weight 1 TCP_CHECK { connect_timeout 10 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } } virtual_server 192.168.122.110 80 { delay_loop 3 lb_algo rr lb_kind DR persistence_timeout 50 protocol TCP real_server 192.168.122.10 80 { weight 1 HTTP_GET { url { path /index.html status_code 200 } connect_timeout 10 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } real_server 192.168.122.20 80 { weight 1 HTTP_GET { url { path /index.html status_code 200 } connect_timeout 10 nb_get_retry 3 delay_before_retry 3 connect_port 80 } } }
以上创建了两个实例lb_one、lb_two ,其中A主机做为VIP1地址的master,B主机做为VIP2地址的master,A、B主机互为backup 。另外还有一个技巧点,在master-backup架构中也可以配置多个VIP地址,只需要在实例的VIP配置中增加地址、并在后面指定对应的虚地址后面的realserver即可。在主备脚架中配置多个VIP的方法如下:
virtual_ipaddress { 192.168.122.100 192.168.122.110 ……………… }
三、realserver主机配置
两台realserver主机的配置启停脚本如下:
[root@lvs01 ~]# cat dr_client.sh #!/bin/bash VIP1=192.168.122.100 VIP2=192.168.122.110 #vip's broadcast BROADCAST=192.168.122.255 . /etc/rc.d/init.d/functions case "1" in start) echo "reparing 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 ifconfig lo:0VIP1 netmask 255.255.255.255 broadcast BROADCAST up ifconfig lo:1VIP2 netmask 255.255.255.255 broadcast BROADCAST up /sbin/route add -hostVIP1 dev lo:0 /sbin/route add -host $VIP2 dev lo:0 ;; stop) ifconfig lo:0 down ifconfig lo:1 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 "Usage: lvs {start|stop}" exit 1 esac
四、验证
启动服务后,查看两台director和realserver主机的地址信息如下:
master hostA主机的IP信息如下:
[root@lvs-dr ~]# ip add show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 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: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 52:54:00:39:42:be brd ff:ff:ff:ff:ff:ff inet 192.168.122.30/24 brd 192.168.122.255 scope global eth0 inet 192.168.122.100/32 scope global eth0 inet6 fe80::5054:ff:fe39:42be/64 scope link valid_lft forever preferred_lft forever
master hostB主机的IP信息如下:
[root@lvs-dr2 ~]# ip add show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 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: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 52:54:00:7b:f2:1a brd ff:ff:ff:ff:ff:ff inet 192.168.122.40/24 brd 192.168.122.255 scope global eth0 inet 192.168.122.110/32 scope global eth0 inet6 fe80::5054:ff:fe7b:f21a/64 scope link valid_lft forever preferred_lft forever
realserver主机的IP信息如下:
[root@lvs01 ~]# ip add show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 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 inet 192.168.122.100/32 brd 192.168.122.255 scope global lo:0 inet 192.168.122.110/32 brd 192.168.122.255 scope global lo:1 inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 52:54:00:a9:3b:6a brd ff:ff:ff:ff:ff:ff inet 192.168.122.10/24 brd 192.168.122.255 scope global eth0 inet6 fe80::5054:ff:fea9:3b6a/64 scope link valid_lft forever preferred_lft forever
以上可以看到,VIP在master节点上可以看到,另一个VIP同样只在该实例的master上可以看到,在两台realserver上的回环地址上有两个VIP地址。
分别到各VIP的主节点上通过ipvadm查看,可以获取到对的连接信息,如下:
[root@lvs-dr ~]# ipvsadm -Ln IP Virtual Server version 1.2.1 (size=4096) Prot LocalAddress:Port Scheduler Flags -> RemoteAddress:Port Forward Weight ActiveConn InActConn TCP 192.168.122.100:80 rr persistent 1 -> 192.168.122.10:80 Route 1 0 12 -> 192.168.122.20:80 Route 1 0 11 TCP 192.168.122.110:80 rr persistent 1 -> 192.168.122.10:80 Route 1 0 0 -> 192.168.122.20:80 Route 1 0 0
更详细的测试步骤略过 。