saltstack 進行高可用nginx集羣搭建

以下文章中涉及nginx 基於saltstack的搭建可參看的我的博客 saltstack 自動化部署 nginx（源碼編譯）
實驗拓撲以及涉及的文件目錄如下：

進行keepalived 安裝腳本的編寫

 [root@server1 ~]# vim /srv/salt/keepalived/install.sls
 include:
   - pkgs.make   #  此種包含着常的安裝依賴性


 kp.install:     # keepalived的源碼編譯
   file.managed:     # 文件加管理，向客戶端主機，推送源碼包
     - name: /mnt/keepalived-2.0.6.tar.gz
     - source: salt://keepalived/files/keepalived-2.0.6.tar.gz

   cmd.run:     # 執行解壓與編譯命令
     - 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
                # 在客戶端主機中有此文件後，將不再重複編譯過程
 /etc/keepalived:    # 進行keepalived配置文件目錄建立
   file.directory:
     - mode: 755

 /etc/sysconfig/keepalived:    # 建立軟連接，
   file.symlink:
     - target: /usr/local/keepalived/etc/sysconfig/keepalived

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

進行keepalived 服務腳本的編寫

 include:
   - keepalived.install   # 此腳本中包含install的內容

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

 kp-service:          
   file.managed:       # 文件管理，管理keepalived啓動腳本
     - name: /etc/init.d/keepalived
     - source: salt://keepalived/files/keepalived
     - mode: 755
   service.running:
     - name: keepalived
     - reload: True
     - watch:          # 監控keepalived 配置文件
       - file: /etc/keepalived/keepalived.conf

keepalived 配置文件模版編寫

 [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 }}     # 調用 keepalived.service腳本中的變量
     interface eth0
     virtual_router_id {{ VRID }}  # 調用 keepalived.service腳本中的變量
     priority {{ PRIORITY }}   # 調用 keepalived.service腳本中的變量
     advert_int 1
     authentication {
         auth_type PASS
         auth_pass 1111
     }
     virtual_ipaddress {
         172.25.21.100     # 設定vip
     }
 }

服務腳本中pillor的編寫

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

進行pillar top文件的編寫

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

salt top 文件的編寫

 [root@server1 ~]# vim /srv/salt/top.sls
 base:
   'server1':                   # 在top 文件中進行聲明
     - haproxy.install
     - keepalived.service       
   'server4':
     - haproxy.install
     - keepalived.service
   'server2':
     - apache.service
   'server3':
     - nginx.service

編輯完成進行向各主機推送

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

以上，簡單的http 服務器 基於 keepalived + haproxy 的高可用負載均衡集羣已自動搭建完成。若想擴展業務，只需要添加minion主機，並修改相應的文件腳本即可

進行haproxy的高可用

我們建立的上述集羣是有缺陷的，沒有對haproxy進行健康檢查的，若是haproxy宕機，keepalived服務正常啓動，還是無法做到對後端web服務器負載均衡

爲了解決這個缺陷，我們可以爲keepalived添加haproxy的監控腳本
腳本內容如下：（一個很粗糙的腳本）

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

 /etc/init.d/haproxy status &> /dev/null || /etc/init.d/haproxy  restart &> /dev/null
 # 宕檢查haproxy的狀態，如果返回錯誤，則重啓haproy
 if [ $? -ne 0 ];
 then /etc/init.d/keepalived stop &> /dev/null
 fi
 如果返回值重啓後返回值不爲0，則停止keepalived服務

編輯keepalived 模版文件，並將內容推給各個keepalived主機

 在keealived.conf 開頭加上監控腳本
 vrrp_script check_haproxy {
         script "/etc/keepalived/check_haproxy.sh"
         # 腳本絕對路徑
         interval 2     
         # 腳本刷新的時間      
         weight 2
 }
 ......省略......
     virtual_ipaddress {
         172.25.21.100
     }
     track_script {
         check_haproxy   # 將腳本加到此處，以調用
     }

將此腳本推送到各個keepalived主機中

[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