CentOS 7上安装监控工具monit步骤详解

服务器运维时我们通常使用Zabbix作监视，在这里安装及配置monit，当检测到进程的停止时可自动启动进程。

推荐使用rpmforge源安装monit,因为rpmforge的monit版本较新。

安装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

查看默认的配置文件内容

# 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
监视周期为60秒，日志输出及日志滚动以配置好了。

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相比启动/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相比只是启动/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状态

# 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

确认monit自动启动进程

停止nginx进程之后，查看monit.log文件。

# 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自动启动

配置OS启动时的自动启动。根据系统及版本自动启动的命令不同，在这里介绍CentOS7上配置自动启动的方法。

# 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监视monit

当检测到进程停止时自动启动该进程的环境已经能够搭建好了，但是monit本身停止了就无法检测到了。在这里使用Zabbix监视monit。

监视monit进程

监控对象(Item)

监控对象(Item)