saltstack 进行高可用nginx集群搭建

以下文章中涉及nginx 基于saltstack的搭建可参看的我的博客 saltstack 自动化部署 nginx（源码编译）
实验拓扑以及涉及的文件目录如下：

进行keepalived 安装脚本的编写

 [root@server1 ~]# vim /srv/salt/keepalived/install.sls
 include:
   - pkgs.make   #  此种包含着常的安装依赖性


 kp.install:     # keepalived的源码编译
   file.managed:     # 文件加管理，向客户端主机，推送源码包
     - name: /mnt/keepalived-2.0.6.tar.gz
     - source: salt://keepalived/files/keepalived-2.0.6.tar.gz

   cmd.run:     # 执行解压与编译命令
     - name: cd /mnt && tar zxf keepalived-2.0.6.tar.gz && cd keepalived-2.0.6 && ./configure --prefix=/usr/local/keepalived --with-init=SYSV &>/dev/null && make &>/dev/null && make install &>/dev/null
     - create: /usr/local/keepalived
                # 在客户端主机中有此文件后，将不再重复编译过程
 /etc/keepalived:    # 进行keepalived配置文件目录建立
   file.directory:
     - mode: 755

 /etc/sysconfig/keepalived:    # 建立软连接，
   file.symlink:
     - target: /usr/local/keepalived/etc/sysconfig/keepalived

 /sbin/keepalived:
   file.symlink:
     - target: /usr/local/keepalived/sbin/keepalived

进行keepalived 服务脚本的编写

 include:
   - keepalived.install   # 此脚本中包含install的内容

 /etc/keepalived/keepalived.conf:     # minion中要同步的文件
   file.managed:          # 文件管理模块
     - source: salt://keepalived/files/keepalived.conf   # server上的源文件
     - template: jinja    # jinja 模块
     - context:
         STATE: {{ pillar['state'] }}
         VRID: {{ pillar['vrid'] }}
         PRIORITY: {{ pillar['priority'] }}

 kp-service:          
   file.managed:       # 文件管理，管理keepalived启动脚本
     - name: /etc/init.d/keepalived
     - source: salt://keepalived/files/keepalived
     - mode: 755
   service.running:
     - name: keepalived
     - reload: True
     - watch:          # 监控keepalived 配置文件
       - file: /etc/keepalived/keepalived.conf

keepalived 配置文件模版编写

 [root@server1 ~]# vim /srv/salt/keepalived/files/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 LVS_DEVEL
    vrrp_skip_check_adv_addr
 #   vrrp_strict
    vrrp_garp_interval 0
    vrrp_gna_interval 0
 }

 vrrp_instance VI_1 {
     state {{ STATE }}     # 调用 keepalived.service脚本中的变量
     interface eth0
     virtual_router_id {{ VRID }}  # 调用 keepalived.service脚本中的变量
     priority {{ PRIORITY }}   # 调用 keepalived.service脚本中的变量
     advert_int 1
     authentication {
         auth_type PASS
         auth_pass 1111
     }
     virtual_ipaddress {
         172.25.21.100     # 设定vip
     }
 }

服务脚本中pillor的编写

 [root@server1 ~]# vim /srv/pillar/keepalived/install.sls
 {% if grains['fqdn'] == 'server1' %}
 webserver: keepalived
 state: MASTER      # 定义server1的state
 vrid: 21           # 虚拟id
 priority: 100      # 优先级
 {% elif grains['fqdn'] == 'server4' %}
 webserver: keepalived
 state: BACKUP
 vrid: 21
 priority: 50
 {% endif %}

进行pillar top文件的编写

 [root@server1 ~]# vim /srv/pillar/top.sls
 base:
  '*':
    - web.install
    - keepalived.install   # 在全局声明

salt top 文件的编写

 [root@server1 ~]# vim /srv/salt/top.sls
 base:
   'server1':                   # 在top 文件中进行声明
     - haproxy.install
     - keepalived.service       
   'server4':
     - haproxy.install
     - keepalived.service
   'server2':
     - apache.service
   'server3':
     - nginx.service

编辑完成进行向各主机推送

 [root@server1 ~]# salt '*' state.highstate

以上，简单的http 服务器 基于 keepalived + haproxy 的高可用负载均衡集群已自动搭建完成。若想扩展业务，只需要添加minion主机，并修改相应的文件脚本即可

进行haproxy的高可用

我们建立的上述集群是有缺陷的，没有对haproxy进行健康检查的，若是haproxy宕机，keepalived服务正常启动，还是无法做到对后端web服务器负载均衡

为了解决这个缺陷，我们可以为keepalived添加haproxy的监控脚本
脚本内容如下：（一个很粗糙的脚本）

 [root@server1 files]# vim check_haproxy.sh
 #!/bin/bash

 /etc/init.d/haproxy status &> /dev/null || /etc/init.d/haproxy  restart &> /dev/null
 # 宕检查haproxy的状态，如果返回错误，则重启haproy
 if [ $? -ne 0 ];
 then /etc/init.d/keepalived stop &> /dev/null
 fi
 如果返回值重启后返回值不为0，则停止keepalived服务

编辑keepalived 模版文件，并将内容推给各个keepalived主机

 在keealived.conf 开头加上监控脚本
 vrrp_script check_haproxy {
         script "/etc/keepalived/check_haproxy.sh"
         # 脚本绝对路径
         interval 2     
         # 脚本刷新的时间      
         weight 2
 }
 ......省略......
     virtual_ipaddress {
         172.25.21.100
     }
     track_script {
         check_haproxy   # 将脚本加到此处，以调用
     }

将此脚本推送到各个keepalived主机中

[root@server1 keepalived]# salt '*' state.highstate
server2:
----------
......省略......
Summary for server2
------------
Succeeded: 2            # server2推送成功
Failed:    0
------------
Total states run:     2
Total run time: 495.607 ms
server3:
----------
......省略......
Summary for server3
------------
Succeeded: 9            # server3 推送成功
Failed:    0
------------
Total states run:     9
Total run time:   1.373 s
server4:
----------
......省略......
Summary for server4     # server4推送成功
-------------
Succeeded: 13 (changed=4)
Failed:     0
-------------
Total states run:     13
Total run time:   10.100 s
server1:
----------

......省略......
Summary for server1
-------------
Succeeded: 13 (changed=3)   # server1推送成功
Failed:     0
-------------
Total states run:     13
Total run time:   10.529 s