CentOS 7上安裝監控工具monit步驟詳解

伺服器營運時我們通常使用Zabbix作監視，在這裡安裝及配置monit，當檢測到進程的停止時可自動啟動進程。

推薦使用rpmforge源安裝monit,因為rpmforge的monit版本較新。

安裝monit

# cd /tmp
# rpm -ivh http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el7.rf.x86_64.rpm
# yum install --enablerepo=rpmforge monit
# rpm -q monit
monit-5.6-1.el7.x86_64
# rpm -ql monit
/etc/logrotate.d/monit
/etc/monit.d
/etc/monit.d/logging
/etc/monitrc
/usr/bin/monit
/usr/lib/systemd/system/monit.service
/usr/share/doc/monit-5.6
/usr/share/doc/monit-5.6/CHANGES
/usr/share/doc/monit-5.6/COPYING
/usr/share/doc/monit-5.6/PLATFORMS
/usr/share/doc/monit-5.6/README
/usr/share/man/man1/monit.1.gz
/var/log/monit.log
# monit -V
This is Monit version 5.6
Copyright (C) 2001-2013 Tildeslash Ltd. All Rights Reserved.
2015年9月9日的最新版本是5.6。

配置monit

查看預設的設定檔內容

# grep -v '^#' /etc/monitrc
set daemon  60              # check services at 1-minute intervals
set httpd port 2812 and
    use address localhost  # only accept connection from localhost
    allow localhost        # allow localhost to connect to the server and
    allow admin:monit      # require user 'admin' with password 'monit'
    allow @monit           # allow users of group 'monit' to connect (rw)
    allow @users readonly  # allow users of group 'users' to connect readonly

include /etc/monit.d/*
# cat /etc/logrotate.d/monit
/var/log/monit.log {
    missingok
    notifempty
    size 100k
    create 0644 root root
    postrotate
        /bin/systemctl reload monit.service > /dev/null 2>&1 || :
    endscript
}
# cat /etc/monit.d/logging
# log to monit.log
set logfile /var/log/monit.log
監視周期為60秒，日誌輸出及日誌滾動以配置好了。

配置monit

sshd

check process sshd with pidfile /var/run/sshd.pid
    start program "/usr/bin/systemctl start sshd.service"
    stop program "/usr/bin/systemctl stop sshd.service"
    if failed port 22 protocol ssh then restart
    if 5 restart within 5 cycles then timeout
Apache

CentOS6.5上的配置monit的Apache，和CentOS7相比啟動/停止命令不同而已。

check process apache with pidfile /var/run/httpd/httpd.pid
  start program = "/etc/init.d/httpd start" with timeout 60 seconds
  stop program  = "/etc/init.d/httpd stop"
  if failed host www.zabbix.cc port 80 protocol http
     and request "/readme.html"
     then restart
  if 3 restarts within 5 cycles then timeout
  group apache
Nginx

check process nginx with pidfile /var/run/nginx.pid
  start program = "/usr/bin/systemctl start nginx.service"
  stop program  = "/usr/bin/systemctl stop nginx.service"
MySQL

CentOS6.5上的配置monit的MySQL，和CentOS7相比只是啟動/停止的命令不同。

check process mysqld with pidfile "/var/run/mysqld/mysqld.pid"
    start = "/etc/init.d/mysqld start"
    stop = "/etc/init.d/mysqld stop"
    if failed unixsocket /var/lib/mysql/mysql.sock with timeout 60 seconds then restart
    if 5 restarts within 5 cycles then timeout
MariaDB

check process mariadb with pidfile "/var/run/mariadb/mariadb.pid"
    start = "/usr/bin/systemctl start mariadb.service"
    stop = "/usr/bin/systemctl stop mariadb.service"
    if failed host 127.0.0.1 port 3306 protocol mysql then restart
    if 5 restarts within 5 cycles then timeout

查看monit狀態

# monit status
The Monit daemon 5.6 uptime: 8m

Process 'sshd'
  status                            Running
  monitoring status                 Monitored
  pid                               884
  parent pid                        1
  uptime                            19d 11h 57m
  children                          4
  memory kilobytes                  3016
  memory kilobytes total            19420
  memory percent                    0.0%
  memory percent total              0.5%
  cpu percent                       0.0%
  cpu percent total                 0.0%
  port response time                0.008s to localhost:22 [SSH via TCP]
  data collected                    Sun, 05 Apr 2015 21:41:18

Process 'nginx'
  status                            Running
  monitoring status                 Monitored
  pid                               13963
  parent pid                        1
  uptime                            6m
  children                          3
  memory kilobytes                  2428
  memory kilobytes total            67520
  memory percent                    0.0%
  memory percent total              1.8%
  cpu percent                       0.0%
  cpu percent total                 0.0%
  data collected                    Sun, 05 Apr 2015 21:41:18

Process 'mariadb'
  status                            Running
  monitoring status                 Monitored
  pid                               24790
  parent pid                        24354
  uptime                            10d 4h 36m
  children                          0
  memory kilobytes                  216168
  memory kilobytes total            216168
  memory percent                    5.9%
  memory percent total              5.9%
  cpu percent                       0.0%
  cpu percent total                 0.0%
  port response time                0.000s to 127.0.0.1:3306 [MYSQL via TCP]
  data collected                    Sun, 05 Apr 2015 21:41:18

System 'zabbix.cc'
  status                            Running
  monitoring status                 Monitored
  load average                      [0.00] [0.01] [0.05]
  cpu                               0.8%us 0.1%sy 0.1%wa
  memory usage                      1524496 kB [42.1%]
  swap usage                        0 kB [0.0%]
  data collected                    Sun, 05 Apr 2015 21:41:18

確認monit自動啟動進程

停止nginx進程之後，查看monit.log檔案。

# systemctl stop nginx.service
# tailf /var/log/monit.log
[CST Apr  5 21:35:18] error    : 'nginx' process is not running
[CST Apr  5 21:35:18] info     : 'nginx' trying to restart
[CST Apr  5 21:35:18] info     : 'nginx' start: /usr/bin/systemctl

配置OS自動啟動

配置OS啟動時的自動啟動。根據系統及版本自動啟動的命令不同，在這裡介紹CentOS7上配置自動啟動的方法。

# systemctl list-unit-files | grep monit.service
monit.service                          disabled
# systemctl enable monit.service
ln -s '/usr/lib/systemd/system/monit.service' '/etc/systemd/system/multi-user.target.wants/monit.service'
# systemctl list-unit-files | grep monit.service
monit.service                          enabled
Zabbix監視monit

當檢測到進程停止時自動啟動該進程的環境已經能夠搭建好了，但是monit本身停止了就無法檢測到了。在這裡使用Zabbix監視monit。

監視monit進程

監控對象(Item)

監控對象(Item)

項目	配置
Name	Process monit daemon running
Type	Zabbix agent
Key	proc.num[monit]
資料類型	Numeric(整數)

觸發器（Trigger）

項目	配置
Name	Process monit daemon down
邏輯條件式	{Zabbix server:proc.num[monit].last()}=0
嚴重度	Warning(警告)

監控monit記錄檔

監控對象(Item)

項目	配置
Name	Process monit daemon running
Type	Zabbix agent
Key	log[/var/log/monit,error]
資料類型	日誌(Log)

觸發器（Trigger）

項目	配置
Name	Process monit daemon error
邏輯條件式	(({Zabbix server:log[/var/log/monit,error].regexp(error)})#0)&({Zabbix server:log[/var/log/monit,error].nodata(300)}=0)
嚴重度	Warning(警告)