keepalived原理、配置解析及其应用案例（keepalived双机热备实现）
一、keepalived原理及配置解析
keepalived：vrrp协议的实现
vrrp协议：virtual router redundancy protocol 即虚拟路由器冗余协议
vrrp基本实现及工作流程：
VRRP通过在一组路由器(一个VRRP组)之间共享一个虚拟IP(VIP)解决静态配置的问题，此时仅需要客户端以VIP作为其默认网关即可。
如图为一个基本的VLAN拓扑，其中，Device A、B、C共同组成一个VRRP组，其VIP为10.1.1.1，配置在路由器A的物理接口上，因此A为master路由器，B和C为backup路由器。
VRRP组中，master(路由器A)负责转发发往VIP地址的报文，客户端A、B、C都以此VIP作为其默认网关。一旦master故障，backup路由器B和C中具有最高优先级的路由器将成为master并接管VIP地址，而当原来的master路由器A重新上线时，如果工作在抢占模式下，其将重新成为master路由器。如果工作在非抢占模式下，其将作为backup路由器备用。
VRRP是一个“选举”协议，它能够动态地将一个虚拟路由器的责任指定至同一个VRRP组中的其它路由器上，从而消除了静态路由配置的单点故障。
VRRP术语：
VRRP虚拟路由(VRRP router)：由一个master路由器和多个backup路由器组成，主机将虚拟路由器作为默认网关。
VRID(虚拟路由器标志)：同一个虚拟路由器VRID必须唯一。
master路由器：虚拟路由器中承担报文转发任务的路由器。
backup路由器：master路由器故障时，能够接替master路由器工作的路由器。
优先级：vrrp根据优先级高低确定虚拟路由器组中每台路由器地位。
IP地址拥有者（IP Address Owner）：如果一个VRRP设备将虚拟路由器IP地址作为真实的接口地址，则该设备被称为IP地址拥有者。如果IP地址拥有者是可用的，通常它将成为Master。
抢占模式：backup路由器工作于该模式下时，当它收到vrrp报文后，会将自身优先级与报文中的优先级作比较，如果自身优先级高，则会主动抢占成为master路由器，否则维持原状。
非抢占模式：backup路由器工作于该模式下时，只要master路由器不出现故障，则维持原状。
VRRP的优势：
冗余：可以使用多个路由器设备作为LAN客户端的默认网关，大大降低了默认网关成为单点故障的可能性；
负载共享：允许来自LAN客户端的流量由多个路由器设备所共享；
多VRRP组：在一个路由器物理接口上可配置多达255个VRRP组；
多IP地址：基于接口别名在同一个物理接口上配置多个IP地址，从而支持在同一个物理接口上接入多个子网；
抢占：在master故障时允许优先级更高的backup成为master；
通告协议：使用IANA所指定的组播地址224.0.0.18进行VRRP通告；
VRRP追踪：基于接口状态来改变其VRRP优先级来确定最佳的VRRP路由器成为master；
keepalived的体系结构
如图：
Keepalived大致分为两层空间：user space和kernel space。
watchdog：负责监控Checkers和VRRP Stack进程的状况。
Checkers：负责真实服务器的健康检查（health checking），是keepalived最主要的功能。换句话说，可以没有VRRP Stack，但是不能没有Checkers。
VRRP Stack：负责负载均衡器之间的失败切换FailOver，如果只有一个负载均衡器，则VRRP Stack不是必须的。
IPVS Wrappers：用来发送设定的规则（通过ipvsadm设置的规则）到内核ipvs的代码。
NetlinkReflector：用来设定VRRP的VIP等。
keepalived.conf配置组成：
global_defs{......}
vrrp_script XXX{......}
vrrp_instance VI_X{......}
virtual_server IPPORT { ...... }
orvirtual_server fwmark int { ...... }
orvirtual_server group string { ...... }
keepalived.conf常用参数解析：
以下为双主模式下keepalived+nginx配置。
[root@testkeepalived]# cat keepalived.conf
! ConfigurationFile for keepalived
global_defs {
notification_email {
#notification_email：指定当keepalived出现问题时，发送邮件给哪些用户。
root@localhost
}
notification_email_from field@localhost
#notification_emai_from：发送邮件时，邮件的源地址。
smtp_server 127.0.0.1
#smtp_server
smtp_connect_timeout 30
#指定smtp服务器连接的超时时间，单位s。
router_id test.field.com
#router_id：指定标识该机器的route_id. 如：route_id LVS_DEVEL
vrrp_mcast_group4 224.18.0.200
#vrrp_mcast_group4224.0.0.18：指定发送VRRP组播消息使用的IPV4组播地址。默认是224.0.0.18
#vrrp_mcast_group6ff02::12 指定发送VRRP组播消息所使用的IPV6组播地址。默认是ff02::12
}
#vrrp_script添加一个周期性执行的脚本。脚本的退出状态码会调用它的所有的VRRP Instance记录。
#至少应该有一个VRRP实例调用它并且优先级不能为0.优先级范围是1-254.
vrrp_scriptchk_maintanance {
script "[[ -f /etc/keepalived/down]] && exit 1 || exit 0"
#手工编写测试keepalived脚本，如果down文件存在则优先级-2
interval 1
#interval多长时间检查一次
#如果失败返回1权重-2
weight -2
}
vrrp_scriptchk_nginx {
script "killall -0 nginx &>/dev/null"
#nginx检测脚本，nginx服务是否在线。
interval 1
#interval多长时间检查一次
#如果失败返回1权重-2
weight -5
}
vrrp_instanceVI_1 {
state MASTER
#stateMASTER|BACKUP：指定该keepalived节点的初始状态。
interface eth0
#interface eth0：vrrp实例绑定的接口，用于发送VRRP包，注意要与本机借口一致。
virtual_router_id 51
#virtual_router_id51：指定VRRP实例ID，范围是0-255，注意每个vip实例id必须严格一致。
priority 100
#priority 100：指定优先级，优先级高的将成为MASTER。
advert_int 1
#advert_int 1：指定发送VRRP通告的间隔。单位是秒。
authentication {
auth_type PASS
#auth_typePASS|AH：指定认证方式。PASS简单密码认证(推荐),AH:IPSEC认证(不推荐)。
auth_pass 4e78bb3a
#auth_pass 1234：指定认证所使用的密码，可用“openssl rand -hex 4”生成8位随机码
}
virtual_ipaddress {
192.168.88.80/16 dev eth0 label eth0:0
#指定VIP地址/掩码，接口名，别名，可只是用IP/掩码。
}
track_script {
#track_script 添加一个track脚本，即vrrp_script配置的脚本。每个周期通过调用脚本，会监控服务状态。
chk_nginx
}
#通知脚本
notify_master"/etc/keepalived/notify.sh master"
notify_backup"/etc/keepalived/notify.sh backup"
notify_fault"/etc/keepalived/notify.sh fault"
}
vrrp_instanceVI_2 {
state BACKUP
interface eth0
virtual_router_id 61
priority 99
advert_int 1
#nopreempt
#设置为非抢占模式。默认是抢占模式，设置非抢占模式时，即使高优先级的机器已经上线，也允许低优先级的机器继续成为MASTER。注意使用非抢占模式时，初始化状态必须为BACKUP。
#preempt_delay：
#设置抢占延迟。单位是秒，范围是0---1000，默认是0.发现低优先级的MASTER后多少秒开始抢占。
authentication {
auth_type PASS
auth_pass Te7UYb3a
}
virtual_ipaddress {
192.168.88.90/16 dev eth0 label eth0:1
}
track_script {
#track_script 调用脚本
chk_nginx
}
notify_master"/etc/keepalived/notify.sh master"
notify_backup"/etc/keepalived/notify.sh backup"
notify_fault"/etc/keepalived/notify.sh fault"
}
#virtual_server192.168.200.100 443 {
# delay_loop 6
# delay_loop
# lb_algo rr
# lb_argo rr|wrr|lc|wlc|lblc|sh|dh：LVS调度算法。默认为轮询。
# lb_kind NAT
# lb_kind NAT|DR|TUN：LVS模式。
# nat_mask 255.255.255.0
# persistence_timeout 50
#persistence_timeout360：持久化超时时间，单位是秒。默认是6分钟。
# protocol TCP
# protocol TCP|UDP|SCTP：使用的4层协议。默认TCP.
# sorry_server 192.168.200.200 1358
#sorry_server
# real_server 192.168.201.100 443 {
# weight 1
#weight
# SSL_GET {
# url {
# path /
#path
# digestff20ad2481f97b1754ef3e12ecd3a9cc
#digest
# }
# url {
# path /mrtg/
# digest 9b3a0c85a887a256d6939da88aabd8cd
# }
# connect_timeout 3
# nb_get_retry 3
#nb_get_retry
# delay_before_retry 3
#delay_before_retry
# }
# }
#}
二、keepalived应用：
使用keepalived实现双机热备：
master：CentOS release 6.3 (Final) 192.168.88.130 test.field.com
backup：CentOS release 6.3 (Final) 192.168.88.131 www.field.com
以下演示keepalived安装到实现双击热备全流程。为便于观测，为keepalived添加日志记录功能，该功能为非必须功能。
[root@test ~]#yum install keepalived -y
keepalived相关文件：
[root@test ~]#rpm -ql keepalived
/etc/keepalived
/etc/keepalived/keepalived.conf
/etc/rc.d/init.d/keepalived
/etc/sysconfig/keepalived
/usr/bin/genhash
/usr/libexec/keepalived
/usr/sbin/keepalived
/usr/share/doc/keepalived-1.2.13
/usr/share/doc/keepalived-1.2.13/AUTHOR
/usr/share/doc/keepalived-1.2.13/CONTRIBUTORS
/usr/share/doc/keepalived-1.2.13/COPYING
/usr/share/doc/keepalived-1.2.13/ChangeLog
/usr/share/doc/keepalived-1.2.13/NOTE_vrrp_vmac.txt
/usr/share/doc/keepalived-1.2.13/README
/usr/share/doc/keepalived-1.2.13/TODO
/usr/share/doc/keepalived-1.2.13/VERSION
/usr/share/doc/keepalived-1.2.13/keepalived.conf.SYNOPSIS
/usr/share/doc/keepalived-1.2.13/samples
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.HTTP_GET.port
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.IPv6
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.SMTP_CHECK
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.SSL_GET
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.fwmark
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.inhibit
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.misc_check
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.misc_check_arg
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.quorum
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.sample
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.status_code
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.track_interface
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.virtual_server_group
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.virtualhost
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.vrrp
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.vrrp.localcheck
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.vrrp.lvs_syncd
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.vrrp.routes
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.vrrp.scripts
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.vrrp.static_ipaddress
/usr/share/doc/keepalived-1.2.13/samples/keepalived.conf.vrrp.sync
/usr/share/doc/keepalived-1.2.13/samples/sample.misccheck.smbcheck.sh
/usr/share/man/man1/genhash.1.gz
/usr/share/man/man5/keepalived.conf.5.gz
/usr/share/man/man8/keepalived.8.gz
/usr/share/snmp/mibs/KEEPALIVED-MIB.txt
HAcluster配置前提
1、本机的主机名，要与hostname（uname -n）获得的名称保持一致
centos6：/etc/sysconfig/network
master:
[root@test ~]#cat /etc/issue
CentOS release6.3 (Final)
Kernel \r on an\m
能互相解析域名，建议直接写进/etc/hosts解析
[root@test ~]#hostname
test.field.com
[root@test ~]#vi /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4localhost4.localdomain4
::1 localhost localhost.localdomainlocalhost6 localhost6.localdomain6
192.168.88.130 test.field.com test
192.168.88.131 www.field.com www
backup:
[root@www ~]#cat /etc/issue
CentOS release6.3 (Final)
Kernel \r on an\m
[root@www ~]#hostname
www.field.com
[root@www ~]# vi /etc/hosts
# 127.0.0.1 localhost localhost.localdomain localhost4localhost4.localdomain4
# ::1 localhost localhost.localdomainlocalhost6 localhost6.localdomain6
192.168.88.130 test.field.com test
192.168.88.131 www.field.com www
192.168.88.131 web1.field.com web1
192.168.88.131 img1.field.com img1
2、相互之间能互相通信，建议配置免密ssh。
[root@test ~]# ssh-keygen -t rsa-P ''
Generatingpublic/private rsa key pair.
Enter file inwhich to save the key (/root/.ssh/id_rsa):
Youridentification has been saved in /root/.ssh/id_rsa.
Your public keyhas been saved in /root/.ssh/id_rsa.pub.
The keyfingerprint is:
43:41:0c:f7:2a:3f:5b:77:a3:8c:8b:3a:ca:04:28:[email protected]
The key'srandomart image is:
+--[ RSA2048]----+
| .++ |
| ..o |
| . .. |
| o . . . |
|o E . S |
|. . o. |
| . o. . o |
| o . = + o . |
| o..oo o.o |
+-----------------+
本机免密登录：
[root@test ~]# cat .ssh/id_rsa.pub>> .ssh/authorized_keys
[root@test ~]#ssh test
Last login: SunApr 22 13:56:44 2018 from test.field.com
[root@test ~]#ll .ssh/authorized_keys
-rw-r--r-- 1root root 401 4月 22 15:47 .ssh/authorized_keys
authorized_keys权限建议设置为600
[root@test ~]# chmod go=.ssh/authorized_keys
[root@test ~]#ll .ssh/authorized_keys
-rw------- 1root root 401 4月 22 15:47 .ssh/authorized_keys
scp到备机，实现免密ssh
[root@test ~]# scp -p .ssh/id_rsa.ssh/authorized_keys www:/root/.ssh
The authenticityof host 'www (192.168.88.131)' can't be established.
RSA keyfingerprint is da:52:ca:c5:e6:c5:3a:de:5d:bc:07:ed:86:e6:ac:44.
Are you sure youwant to continue connecting (yes/no)? yes
Warning:Permanently added 'www' (RSA) to the list of known hosts.
root@www'spassword:
id_rsa 100% 1675 1.6KB/s 00:00
authorized_keys 100% 401 0.4KB/s 00:00
3、各节点时间必须同步
[root@test ~]# date; ssh www'date'
2018年 04月 22日 星期日 16:16:24 CST
2018年 04月 22日 星期日 16:16:24 CST
4、确保iptables及selinux不会成为服务阻碍
service iptables stop
service selinux stop
案例1、keepalived配置单个vip实例实现双机热备
openssl生成随机码做密码
[root@test ~]#openssl rand -hex 4
4e78bb3a
[root@testkeepalived]# vim keepalived.conf
! ConfigurationFile for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from kaadimin@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id test.field.com
vrrp_mcast_group4 224.18.0.200
}
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 4e78bb3a
}
virtual_ipaddress {
192.168.88.80/16 dev eth0 label eth0:0
}
}
#virtual_server192.168.200.100 443 {
# delay_loop 6
# lb_algo rr
# lb_kind NAT
:.,$s/^/#/g 从当前行到最后一行搜索行首添加#号
backup安装keepalived，scp主机配置备机，并修改配置。
[root@test keepalived]# scpkeepalived.conf www:/etc/keepalived/
keepalived.conf 100% 3631 3.6KB/s 00:00
www节点
[root@www ssh]#cd /etc/keepalived/
[root@wwwkeepalived]# ll
总用量 4
-rw-r--r--. 1root root 3631 4月 22 16:42 keepalived.conf
[root@wwwkeepalived]# vi keepalived.conf
! ConfigurationFile for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from kaadimin@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id www.field.com
vrrp_mcast_group4 224.18.0.200
}
vrrp_instanceVI_1 {
state BACKUP
interface eth1
virtual_router_id 51
priority 98
advert_int 1
authentication {
auth_type PASS
auth_pass 4e78bb3a
}
virtual_ipaddress {
192.168.88.80/16 dev eth1 label eth1:0
}
}
启动主备机keepalived
[root@test keepalived]# servicekeepalived start;ssh www 'service keepalived start'
正在启动 keepalived：[确定]
正在启动 keepalived：[确定]
[root@testkeepalived]# ps aux |grep keepalived
root 21200 0.0 0.2 109764 1136 ? Ss 16:45 0:00 /usr/sbin/keepalived -D
root 21201 0.0 0.7 111868 2860 ? S 16:45 0:00 /usr/sbin/keepalived -D
root 21202 0.0 0.4 111868 1956 ? S 16:45 0:00 /usr/sbin/keepalived -D
root 21244 0.0 0.2 103268 864 pts/2 S+ 16:47 0:00 grep keepalived
ifconfig可以发现master主节点已启用vip
[root@test log]#ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:4C:04:CC
inet addr:192.168.88.130 Bcast:192.168.88.255 Mask:255.255.255.0
inet6 addr:fe80::20c:29ff:fe4c:4cc/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:341231 errors:0 dropped:0overruns:0 frame:0
TX packets:120981 errors:0 dropped:0overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:493162689 (470.3 MiB) TX bytes:12197825 (11.6 MiB)
eth0:0 Linkencap:Ethernet HWaddr00:0C:29:4C:04:CC
inetaddr:192.168.88.80 Bcast:0.0.0.0 Mask:255.255.0.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:521786 errors:0 dropped:0overruns:0 frame:0
TX packets:521786 errors:0 dropped:0overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3963721429 (3.6 GiB) TX bytes:3963721429 (3.6 GiB)
也可以使用“ip addr list”命令查看IP
[root@test log]#ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0:
link/ether 00:0c:29:4c:04:cc brdff:ff:ff:ff:ff:ff
inet 192.168.88.130/24 brd 192.168.88.255scope global eth0
inet192.168.88.80/16 scope global eth0:0
inet6 fe80::20c:29ff:fe4c:4cc/64 scope link
valid_lft forever preferred_lft forever
backup节点：备用节点未启用vip
[root@wwwkeepalived]# ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth1:
link/ether 00:0c:29:e3:90:19 brdff:ff:ff:ff:ff:ff
inet 192.168.88.131/24 brd 192.168.88.255scope global eth1
inet6 fe80::20c:29ff:fee3:9019/64 scopelink
valid_lft forever preferred_lft forever
[root@test ~]#man keepalived
案例2、配置keepalived记录日志
[root@testsysconfig]# vim /etc/sysconfig/keepalived
# Options forkeepalived. See `keepalived --help' output and keepalived(8) and
#keepalived.conf(5) man pages for a list of all options. Here are the most
# common ones :
#
# --vrrp -P Only run with VRRP subsystem.
# --check -C Only run with Health-checker subsystem.
#--dont-release-vrrp -V Dont remove VRRP VIPs & VROUTEs ondaemon stop.
#--dont-release-ipvs -I Dont remove IPVS topology on daemon stop.
#--dump-conf -d Dump the configuration data.
#--log-detail -D Detailed log messages.
#--log-facility -S 0-7 Set local syslog facility(default=LOG_DAEMON)
#
KEEPALIVED_OPTIONS="-D -S3"
[root@test log]#vi /etc/rsyslog.conf
#添加如下内容
local3.* /var/log/keepalived.log
[root@test log]#service rsyslog restart
关闭系统日志记录器：[确定]
启动系统日志记录器：[确定]
backup节点同样配置：
[root@wwwkeepalived]# vim/etc/sysconfig/keepalived
# Options for keepalived.See `keepalived --help' output and keepalived(8) and
#keepalived.conf(5) man pages for a list of all options. Here are the most
# common ones :
#
# --vrrp -P Only run with VRRP subsystem.
# --check -C Only run with Health-checker subsystem.
#--dont-release-vrrp -V Dont remove VRRP VIPs & VROUTEs ondaemon stop.
#--dont-release-ipvs -I Dont remove IPVS topology on daemon stop.
#--dump-conf -d Dump the configuration data.
#--log-detail -D Detailed log messages.
#--log-facility -S 0-7 Set local syslog facility(default=LOG_DAEMON)
#
KEEPALIVED_OPTIONS="-D -S3"
[root@www log]#vi /etc/rsyslog.conf
#添加如下内容
local3.* /var/log/keepalived.log
[root@wwwkeepalived]# service rsyslog restart
关闭系统日志记录器：[确定]
启动系统日志记录器：[确定]
重启keepalived，可以发现启动日志被记录。
[root@test sysconfig]# tail -n 30/var/log/keepalived.log
Apr 22 17:03:25test Keepalived[21603]: Starting Keepalived v1.2.13 (03/19,2015)
Apr 22 17:03:25test Keepalived[21604]: Starting Healthcheck child process, pid=21605
Apr 22 17:03:25test Keepalived_healthcheckers[21605]: Initializing ipvs 2.6
Apr 22 17:03:25test Keepalived[21604]: Starting VRRP child process, pid=21606
Apr 22 17:03:25test Keepalived_vrrp[21606]: Netlink reflector reports IP 192.168.88.130 added
Apr 22 17:03:25test Keepalived_vrrp[21606]: Netlink reflector reports IPfe80::20c:29ff:fe4c:4cc added
Apr 22 17:03:25test Keepalived_healthcheckers[21605]: Netlink reflector reports IP192.168.88.130 added
Apr 22 17:03:25test Keepalived_vrrp[21606]: Registering Kernel netlink reflector
Apr 22 17:03:25test Keepalived_vrrp[21606]: Registering Kernel netlink command channel
Apr 22 17:03:25test Keepalived_vrrp[21606]: Registering gratuitous ARP shared channel
Apr 22 17:03:25test Keepalived_healthcheckers[21605]: Netlink reflector reports IPfe80::20c:29ff:fe4c:4cc added
Apr 22 17:03:25test Keepalived_healthcheckers[21605]: Registering Kernel netlink reflector
Apr 22 17:03:25test Keepalived_healthcheckers[21605]: Registering Kernel netlink commandchannel
Apr 22 17:03:25test Keepalived_vrrp[21606]: Opening file '/etc/keepalived/keepalived.conf'.
Apr 22 17:03:25test Keepalived_healthcheckers[21605]: Opening file '/etc/keepalived/keepalived.conf'.
Apr 22 17:03:25test Keepalived_vrrp[21606]: Configuration is using : 62934 Bytes
Apr 22 17:03:25test Keepalived_vrrp[21606]: Using LinkWatch kernel netlink reflector...
Apr 22 17:03:25test Keepalived_healthcheckers[21605]: Configuration is using : 7461 Bytes
Apr 22 17:03:25test Keepalived_vrrp[21606]: VRRP sockpool: [ifindex(2), proto(112),unicast(0), fd(10,11)]
Apr 22 17:03:25test Keepalived_healthcheckers[21605]: Using LinkWatch kernel netlinkreflector...
Apr 22 17:03:26test Keepalived_vrrp[21606]: VRRP_Instance(VI_1) Transition to MASTER STATE
Apr 22 17:03:27test Keepalived_vrrp[21606]: VRRP_Instance(VI_1) Entering MASTER STATE
Apr 22 17:03:27test Keepalived_vrrp[21606]: VRRP_Instance(VI_1) setting protocol VIPs.
Apr 22 17:03:27test Keepalived_healthcheckers[21605]: Netlink reflector reports IP192.168.88.80 added
Apr 22 17:03:27test Keepalived_vrrp[21606]: VRRP_Instance(VI_1) Sending gratuitous ARPs oneth0 for 192.168.88.80
Apr 22 17:03:32test Keepalived_vrrp[21606]: VRRP_Instance(VI_1) Sending gratuitous ARPs oneth0 for 192.168.88.80
测试1、关闭master节点keepalived
[root@test log]#ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0:
link/ether 00:0c:29:4c:04:cc brdff:ff:ff:ff:ff:ff
inet 192.168.88.130/24 brd 192.168.88.255scope global eth0
inet 192.168.88.80/16 scope global eth0:0
inet6 fe80::20c:29ff:fe4c:4cc/64 scope link
valid_lft forever preferred_lft forever
[root@test log]#service keepalived stop
停止 keepalived：[确定]
[root@test log]#ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0:
link/ether 00:0c:29:4c:04:cc brdff:ff:ff:ff:ff:ff
inet 192.168.88.130/24 brd 192.168.88.255scope global eth0
inet6 fe80::20c:29ff:fe4c:4cc/64 scope link
valid_lft forever preferred_lftforever
可以发现备用节点vip已启动
[root@wwwkeepalived]# ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth1:
link/ether 00:0c:29:e3:90:19 brdff:ff:ff:ff:ff:ff
inet 192.168.88.131/24 brd 192.168.88.255scope global eth1
inet192.168.88.80/16 scope global eth1:0
inet6 fe80::20c:29ff:fee3:9019/64 scopelink
valid_lft forever preferred_lft forever
测试2、重新启动，因为工作在抢占模式下，主节点会抢回vip
[root@test log]#service keepalived start
正在启动 keepalived：[确定]
[root@test log]#ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0:
link/ether 00:0c:29:4c:04:cc brdff:ff:ff:ff:ff:ff
inet 192.168.88.130/24 brd 192.168.88.255scope global eth0
inet192.168.88.80/16 scope global eth0:0
inet6 fe80::20c:29ff:fe4c:4cc/64 scope link
valid_lft forever preferred_lft forever
案例3、定义手动监控keepalived
[root@testkeepalived]# vi keepalived.conf
! ConfigurationFile for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from kaadimin@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id test.field.com
vrrp_mcast_group4 224.18.0.200
}
vrrp_script chk_maintanance {
script "[[ -f /etc/keepalived/down]] && exit1 || exit 0 "
interval 1
#interval多长时间检查一次
#如果失败返回1权重-2
weight -2
}
vrrp_instanceVI_1 {
state MASTER
interface eth0
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 4e78bb3a
}
virtual_ipaddress {
192.168.88.80/16 dev eth0 label eth0:0
}
track_script {
#track_script 调用脚本
chk_maintanance
}
}
[root@wwwkeepalived]# vim keepalived.conf
192.168.88.80/16 dev eth0 label eth0:0
virtual_ipaddress {
}
interval 1
! ConfigurationFile for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from kaadimin@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id www.field.com
vrrp_mcast_group4 224.18.0.200
}
vrrp_script chk_maintanance {
script "[[ -f /etc/keepalived/down]] && exit 1 || exit 0 "
interval 1
#interval多长时间检查一次
#如果失败返回1权重-2
weight -2
}
vrrp_instanceVI_1 {
state BACKUP
interface eth1
virtual_router_id 51
priority 99
advert_int 1
authentication {
auth_type PASS
auth_pass 4e78bb3a
}
virtual_ipaddress {
192.168.88.80/16 dev eth1 label eth1:0
}
track_script {
#track_script 调用脚本
chk_maintanance
}
}
[root@testkeepalived]# !1049
servicekeepalived restart;ssh www 'service keepalived restart'
停止 keepalived：[确定]
正在启动 keepalived：[确定]
停止 keepalived：[确定]
正在启动 keepalived：[确定]
[root@testkeepalived]# ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0:
link/ether 00:0c:29:4c:04:cc brdff:ff:ff:ff:ff:ff
inet 192.168.88.130/24 brd 192.168.88.255scope global eth0
inet 192.168.88.80/16 scope global eth0:0
inet6 fe80::20c:29ff:fe4c:4cc/64 scope link
valid_lft forever preferred_lft forever
测试1、新建down文件，测试keepalived切换功能
[root@test keepalived]# touch down
此时可以发现，master移除vip
[root@testkeepalived]# ip addr list
1: lo:
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:
link/ether 00:0c:29:4c:04:cc brd ff:ff:ff:ff:ff:ff
inet 192.168.88.130/24 brd 192.168.88.255scope global eth0
inet6 fe80::20c:29ff:fe4c:4cc/64 scope link
valid_lft forever preferred_lft forever
[root@testsysconfig]# tail -f /var/log/keepalived.log
Apr 22 18:14:31 test Keepalived_vrrp[24108]:VRRP_Script(chk_maintanance) failed
Apr 22 18:14:33 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) Received higher prio advert
Apr 22 18:14:33 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) Entering BACKUP STATE
Apr 22 18:14:33 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) removing protocol VIPs.
Apr 22 18:14:33 test Keepalived_healthcheckers[24107]:Netlink reflector reports IP 192.168.88.80 removed
观测backup节点，可以发现意启用vip
[root@wwwkeepalived]# ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth1:
link/ether 00:0c:29:e3:90:19 brdff:ff:ff:ff:ff:ff
inet 192.168.88.131/24 brd 192.168.88.255scope global eth1
inet192.168.88.80/16 scope global eth1:0
inet6fe80::20c:29ff:fee3:9019/64 scope link
valid_lft forever preferred_lft forever
[root@www ~]#tail -f /var/log/keepalived.log
Apr 22 18:14:33 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) forcing a new MASTER election
Apr 22 18:14:33 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) forcing a new MASTER election
Apr 22 18:14:34 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) Transition to MASTER STATE
Apr 22 18:14:35 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) Entering MASTER STATE
Apr 22 18:14:35 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) setting protocol VIPs.
Apr 22 18:14:35 www Keepalived_healthcheckers[10523]: Netlinkreflector reports IP 192.168.88.80 added
Apr 22 18:14:35 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) Sending gratuitous ARPs on eth1 for 192.168.88.80
Apr 22 18:14:40 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) Sending gratuitous ARPs on eth1 for 192.168.88.80
测试2、master节点删除down文件
[root@testkeepalived]# rm -rf down
因工作于抢占模式，可以发现，master抢回vip
[root@test keepalived]#ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0:
link/ether 00:0c:29:4c:04:cc brdff:ff:ff:ff:ff:ff
inet 192.168.88.130/24 brd 192.168.88.255scope global eth0
inet192.168.88.80/16 scope global eth0:0
inet6 fe80::20c:29ff:fe4c:4cc/64 scope link
valid_lft forever preferred_lft forever
[root@test sysconfig]# tail -f/var/log/keepalived.log
Apr 22 18:20:52 test Keepalived_vrrp[24108]:VRRP_Script(chk_maintanance) succeeded
Apr 22 18:20:53 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) forcing a new MASTER election
Apr 22 18:20:53 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) forcing a new MASTER election
Apr 22 18:20:54 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) Transition to MASTER STATE
Apr 22 18:20:55 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) Entering MASTER STATE
Apr 22 18:20:55 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) setting protocol VIPs.
Apr 22 18:20:55 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.88.80
Apr 22 18:20:55 test Keepalived_healthcheckers[24107]:Netlink reflector reports IP 192.168.88.80 added
Apr 22 18:21:00 test Keepalived_vrrp[24108]:VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.88.80
backup节点：vip被主节点抢占回去
[root@wwwkeepalived]# ip addr list
1: lo:
link/loopback 00:00:00:00:00:00 brd00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth1:
link/ether 00:0c:29:e3:90:19 brdff:ff:ff:ff:ff:ff
inet 192.168.88.131/24 brd 192.168.88.255scope global eth1
inet6fe80::20c:29ff:fee3:9019/64 scope link
valid_lft forever preferred_lft forever
[root@wwwkeepalived]#
[root@www ~]#tail -f /var/log/keepalived.log
Apr 22 18:20:53 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) Received higher prio advert
Apr 22 18:20:53 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) Entering BACKUP STATE
Apr 22 18:20:53 www Keepalived_vrrp[10524]:VRRP_Instance(VI_1) removing protocol VIPs.
Apr 22 18:20:53 www Keepalived_healthcheckers[10523]: Netlinkreflector reports IP 192.168.88.80 removed