Keepalived 高可用ipvs和nginx服务
Keepalived 高可用ipvs和nginx服务============================================================================概述：
本章讲主要介绍keepalived高可用ipvs服务和nginx服务，内容如下：
[*]keepalived 配置文件中Virtual_server（虚拟服务器）的配置格式及常用参数；
[*]keepalived高可用ipvs-dr模型实验过程详解；
[*]keepalived调用外部辅助脚本实现资源监控及调其优先级；
[*]keepalived高可用nginx服务；
[*]总结keepalined高可用nginx及ipvs的配置示例以及通知脚本
============================================================================
回顾：
Virtual Server（虚拟服务器）： 1.配置参数：★虚拟服务器的配置格式：
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virtual_server IP port |
virtual_server fwmark int
{
...
real_server {
...
}
...
}
★常用参数keepalived高可用的ipvs-dr集群前面讲到用LVS的DR模式来实现Web应用的负载均衡。为了防止LVS服务器自身的单点故障导致整个Web应用无法提供服务，因此还得利用Keepalived实现lvs的高可用性。
1.实验原理：
[*]即客户端访问VIP（域名解析到VIP），LVS接收情况后根据负载均衡调度算法，转发请求到真实服务器，真实服务器接收到客户端请求后，将处理结果直接返回给客户端。
[*]实验原理图如下：（借用别人的）
2.实验环境准备
[*]准备四台虚拟主机，两台作为real_server,两台作为keepalived+lvs-dr模型的调度器；
[*]在两个RS上修改内核参数，来限制arp响应和通告的级别；
[*]配置两台keepalived+lvs-dr调度器的virtual_server
3.ip地址规划：
[*]keepalived+lvs-dr模型的调度器
node1:10.1.252.161
node2:10.1.249.203
[*]要转移的ip地址：
10.1.252.73,把其80端口定义为集群服务
[*]Real_server
RS 1：10.1.252.37
RS 2：10.1.252.153
其80端口分别向外提供web服务
4.实验环境搭建：
1）首先为两台RS准备httpd服务，并提供测试页面如下：
RS 1
RS 2为一台CentOS 6主机
2）接下来我们要修改两台RS的内核参数arp_ignore和arp_announce，然后配置其本地lo网卡的网卡别名作为VIP（配置可参考先前的文档脚本），如下：
RS 1 vip如下：
RS 2 vip如下：
5.配置调度器node1，和node2,的keepalived服务，手动测试看能否调度到后端RS，过程如下：
1）node1配置如下：
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# cat/etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
vrrp_instance VI_1 {
state MASTER
interface eno16777736
virtual_router_id 17
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
2）node2，配置如下;
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# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
vrrp_instance VI_1 {
state BACKUP
interface eno16777736
virtual_router_id 17
priority 98
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
3）在node1上对转移ip：10.1.252.73的80端口定义集群服务，如下：
4）启动node1节点上的keepalived服务，然后在node2上做测试，如下：
启动node1，之后查看ip，因为此时node1为主节点，所以转移ip在node1上，如下：
在node2上做测试，可以看到是以轮询的方式响应，如下：
5）关闭node1上的keepalived服务，使10.1.252.73的地址转移到node2，以同样的方法在node2上定义转移ip的集群服务，在node1上测试发现，同样可以以轮询的方式正常调度到后端的RS服务器。
6.如上，两个节点手动测试都没有问题，清空两个调度器上的定义的集群服务；接下来我们要通过定义keepalived的配置文件来自动生成ipvsadm定义的规则。
1）首先编辑node1的配置文件，定义virtual server（虚拟主机服务），如下：
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# cat keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
vrrp_instance VI_1 {
state MASTER
interface eno16777736
virtual_router_id 17
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
virtual_server 10.1.252.73 80 { # 定义转移ip端口80的集群服务
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
real_server 10.1.252.37 80 { # 定义集群服务包含的RS 1
weight 1 # 权重为1
HTTP_GET { # 定义RS1的健康状态检测
url {
path /
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.1.252.153 80 { # 定义集群服务包含的RS 1
weight 1 # 权重为1
HTTP_GET { # 定义RS1的健康状态检测
url {
path /
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
}
同理，在node2的节点上也添加定义virtual server，如下：
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# catkeepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
vrrp_instance VI_1 {
state BACKUP
interface eno16777736
virtual_router_id 17
priority 98
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
virtual_server 10.1.252.73 80 {
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
real_server 10.1.252.37 80 {
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.1.252.153 80 {
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
}
7.如上，两个节点node1和node2都已经定义好虚拟主机的集群服务，现在我们开始测试。
1）启动node1和node2上的keepalived服务，因为node1为主节点，所以首先连接转移ip的集群服务，如下：
使用curl测试访问发现，以轮询的方式响应，如下：
现在我停止后端主机RS1，再次在node1上使用ipvsadm查看，RS1已经不存在了，使用curl请求，这是只有RS2响应，如下：
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# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP10.1.252.73:80 rr
-> 10.1.252.153:80 Route 1 0 0
You have new mail in /var/spool/mail/root
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# for i in {0..9};do curl http://10.1.252.73 ;done
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 2 CentOS 6.8</h1>
把RS1启动，3s之后ipvsadm规则就又检测到了，使用curl请求，后端主机又是以轮询的方式响应：
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# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP10.1.252.73:80 rr
-> 10.1.252.37:80 Route 1 0 0
-> 10.1.252.153:80 Route 1 0 0
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# for i in {0..9};do curl http://10.1.252.73 ;done
<h1>RS 1</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS 2 CentOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS 2 CentOS 6.8</h1>
如果我们把后端的两台RS都停止服务，发现再使用ipvsadm就检测不到了，使用curl访问，提示拒绝访问，如下：
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# for i in {0..9};do curl http://10.1.252.73 ;done
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
curl: (7) Failed connect to 10.1.252.73:80; Connection refused
8.现在我们就需要定义一个sorry_server，可以用来提醒用户，集群服务出现故障。这里要使用调度器本身的httpd服务来做更合适；并且，要保证两台调度器的web服务都启动起来。
注意：调度器的web服务在这是没有用的，因为80端口直接在INPUT链上已经被劫走，当做集群服务了，所以调度器上的web服务只能当做sorry_server。
1）在node1和node2上定义sorry_server如下：（以node1为例）
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# catkeepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
vrrp_instance VI_1 {
state MASTER
interface eno16777736
virtual_router_id 17
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
virtual_server 10.1.252.73 80 {
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
sorry_server 127.0.0.1 80 # 定义的 sorry_server为本机的80端口
real_server 10.1.252.37 80 {
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.1.252.153 80 {
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
}
2）然后我们编辑本机httpd服务的映射根目录，添加提醒用户的测试页面，如下：
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# echo "<h1>LB Cluster Fault,this is Sorry Server 1</h1>" > /var/www/html/index.html
# cat /var/www/html/index.html
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
3）在后端两台RS停止服务的情况下，使用ipvsadm查看，可以看到有本机的定义的sorry_server，使用curl访问如下：
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# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP10.1.252.73:80 rr
-> 127.0.0.1:80 Route 1 0 0
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# for i in {0..9};do curl http://10.1.252.73 ;done
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
<h1>LB Cluster Fault,this is Sorry Server 1</h1>
4）后端主机只要有一个RS启动，3s之后sorry_server就会下线了，由后端主机提供服务。
如上，整个过程就是利用keepalived高可用lvs-dr负载均衡的web集群。。。
=============================================================================
keepalived实现优先级动态调整；keepalived调用外部的辅助脚本进行资源监控，并根据监控的结果状态能实现优先动态调整；
示例：
我们在前面的试验中，每次如果由主动节点跳转到被动节点，都是手动把keepalived服务停掉才能实现。但是在实际生产环境中，如果我们不想让他停止服务，只是暂时的进行维护，那该怎么办呢？
keeoalived有一个功能，可以调用外部脚本来完成资源监控，然后根据资源监控的结果，来完成优先级的动态调整。
这里我定义一个外部脚本，如果在/etc/keepalived/下存在down文件，则节点优先级减5，编辑配置文件，如下：
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# cat keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
# 定义外部脚本，如果/etc/keepalived/down存在，则返回值为1，否则为0
vrrp_script chk_down {
script "[[ -f /etc/keepalived/down ]] && exit 1 || exit 0"
interval 1 # 每个1s钟检测一次
weight -5 # 优先级减去5
}
vrrp_instance VI_1 {
state MASTER
interface eno16777736
virtual_router_id 17
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736
}
track_script { # 调用定义的外部脚本
chk_down
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
同样的定义在节点node2也编辑过去，然后保存，现在我们来测试，启动node1和node2的keepalived服务，此时node1因为优先级高，所以资源ip在主节点node1，如下：
然后我们在主节点node1的/etc/keepalived下创建一个down文件，可以发现node1的资源ip已经转移到备用节点node2上了，如下：
备用节点查看如下：
现在，我们把主节点node1上的down文件删除，发现1秒钟之后，资源ip又被node1抢了会来，如下：
keepalived高可用nginx服务1.实验拓扑图2.实验环境准备
[*]准备四台虚拟主机，两台作为real_server,两台配置nginx服务作为调度器；
[*]在两台nginx调度器上配置upstream模块，然后proxy反代到两台后端主机
[*]配置两台nginx调度器的virtual_serve
3.ip地址规划和高可用lpvs-dr相同
4.实验环境搭建如下：
1）首先，在作为两台nginx调度器上配置配置upstream模块，然后proxy反代到两台后端主机，如下：
在/etc/nginx/nginx.conf中的http配置段定义后端web服务器组；
在/etc/nginx/conf.d/default.conf的server中定义proxy反向代理
node2上的nginx配置和node1是相同的，这里不在列出。
2）配置node1和node2上的keepalived服务，使用nginx不需要定义virtual_server,如下：
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# cat keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
vrrp_script chk_down {
script "[[ -f /etc/keepalived/down ]] && exit 1 || exit 0"
interval 1
weight -5
}
vrrp_instance VI_1 {
state MASTER
interface eno16777736
virtual_router_id 17
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736
}
track_script {
chk_down
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
5.如上，整个环境及配置就已经完成了，现在，启动主备节点node1上的nginx服务，和keepalived服务，查看主节点node1的ip，发现资源ip在node1上，如下：
1）测试，在客户端请求nginx调度器上的资源ip，可以发现后端web服务器以轮询的方式响应客户端请求，如下：
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# for i in {0..9};do curl http://10.1.252.73;done
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
2）在主节点node1的/etc/keepalived/下创建一个down文件，因为前面定义了一个调用外部脚本，改变其优先级，所以，这时node1节点的优先级降低，资源ip转移到备用节点node2上，再在客户端请求，发现后端web服务不收影响
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# for i in {0..9};do curl http://10.1.252.73;done
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
6.假如资源ip所在nginx调度器服务宕机或者出现故障了，这时，因为不是keepalived服务故障，所以资源ip时不会转移的。这时，我们就要保证在出现故障前把资源ip转移到备用nginx调度器上，所以，这里我们也可以再定义一个外部脚本来监控nginx服务，一旦出现故障就会调用脚本，降低其优先级然后转移资源ip到备用nginx调度器，如下：
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# cat keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
vrrp_script chk_down {
script "[[ -f /etc/keepalived/down ]] && exit 1 || exit 0"
interval 1
weight -5
}
vrrp_script chk_nginx { # 定义检测nginx的外部脚本
script "killall -0 nginx && exit 0 || exit 1"# 如果检测到nginx服务在就返回0（为真），如果不在就返回值1（假）
interval 1 # 每隔1s检测一次
weight -5 # 优先级减5
}
vrrp_instance VI_1 {
state MASTER
interface eno16777736
virtual_router_id 17
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736
}
track_script {
chk_down
chk_nginx # 调用此脚本
}
notify_master "/etc/keepalived/notify.sh master"
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
实验如下：
1）现在资源ip在主节点node1上，此时访问资源ip可以正常响应；现在我们把node1上的nginx服务进程杀掉，再去访问，发现请求不到资源，资源ip也没有转移到备用节点node2，如下：
2）在配置文件中，定义调用检查nginx服务的脚本后，我们再去做上面的实验，发现资源ip在停止服务前减低优先级，把资源ip转移到备用nginx调度器上，如下：
杀掉node1的nginx服务，发现资源ip已经不在了
请求服务，发现仍然可以访问
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# for i in {0..9};do curl http://10.1.252.73;done
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
<h1>RS 1</h1>
<h1>RS2 CentCOS 6.8</h1>
查看备用nginx调度器node2，发现资源ip成功转移过来，如下：
3）当一个节点nginx服务出现故障，我们就要立即去修复，或者重启服务，如果不想手动去修改，可以编辑通知脚本，在主节点变为MASTER和BACKUP都重启nginx服务，如下：
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# cat notify.sh
#!/bin/bash
#
contact='root@localhost'
notify() {
mailsubject="$(hostname) to be $1,vip floating"
mailbody="$(date +'%F %T'): vrrp transition, $(hostname) changed to be $1"
echo "$mailbody" |mail -s "$mailsubject" $contact
}
case $1 in
master)
notify master
systemctl restart nginx.service
;;
backup)
notify backup
systemctl restart nginx.service
;;
fault)
notify fault
;;
*)
echo "Usage: $(basename $0) {master|backup|fault}"
exit 1
;;
esac
现在我再把主节点的nginx服务kill掉，发现主节点资源ip转移到备用nginx节点node2，但是马上nginx服务就又启动起来了，资源ip又转移到主节点node1，如下：
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# killall nginx # 杀掉node1的nginx服务
# ip a l
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:21:c9:43 brd ff:ff:ff:ff:ff:ff
inet 10.1.252.161/16 brd 10.1.255.255 scope global eno16777736
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe21:c943/64 scope link # 资源ip转移
valid_lft forever preferred_lft forever
# =====================================================================================
# ip a l
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:21:c9:43 brd ff:ff:ff:ff:ff:ff
inet 10.1.252.161/16 brd 10.1.255.255 scope global eno16777736
valid_lft forever preferred_lft forever
inet 10.1.252.73/16 scope global secondary eno16777736# 资源ip又被抢占回来了
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe21:c943/64 scope link
valid_lft forever preferred_lft forever
查看node2的日志，也可以发现资源在短时间内转移了2次
如上就是整个keepalived高可用nginx服务的整个过程。。。
=====================================================================
总结：
1.keepalived高可用nginx主节点配置示例：
2.高可用nginx通知脚本
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#!/bin/bash
#
contact='root@localhost'
notify() {
mailsubject="$(hostname) to be $1,vip floating"
mailbody="$(date +'%F %T'): vrrp transition, $(hostname) changed to be $1"
echo "$mailbody" |mail -s "$mailsubject" $contact
}
case $1 in
master)
notify master
systemctl restart nginx.service
;;
backup)
notify backup
systemctl restart nginx.service
;;
fault)
notify fault
;;
*)
echo "Usage: $(basename $0) {master|backup|fault}"
exit 1
;;
esac
3.高可用ipvs+dr主机点配置示例
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# catkeepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id node1
vrrp_mcast_group4 224.0.100.19
}
vrrp_instance VI_1 {
state MASTER
interface eno16777736
virtual_router_id 17
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass f7111b2e
}
virtual_ipaddress {
10.1.252.73/16 dev eno16777736# 要转移的资源ip
}
notify_master "/etc/keepalived/notify.sh master"# 调用通知脚本
notify_backup "/etc/keepalived/notify.sh backup"
notify_fault "/etc/keepalived/notify.sh fault"
}
virtual_server 10.1.252.73 80 { # 定义转移资源ip上的集群服务
delay_loop 3
lb_algo rr
lb_kind DR
protocol TCP
sorry_server 127.0.0.1 80 # 定义的 sorry_server为本机的80端口
real_server 10.1.252.37 80 { # 定义后端Real_server所提供的80服务
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
real_server 10.1.252.153 80 {
weight 1
HTTP_GET {
url {
path /
status_code 200
}
connect_timeout 1
nb_get_retry 3
delay_before_retry 1
}
}
}
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