Supervisor是一个进程监控程序。
满足的需求是：我现在有一个进程需要每时每刻不断的跑，但是这个进程又有可能由于各种原因有可能中断。当进程中断的时候我希望能自动重新启动它，此时，我就需要使用到了Supervisor.
先弄懂两个命令:
supervisord : supervisor的服务器端部分，启动supervisor就是运行这个命令
supervisorctl：启动supervisor的命令行窗口。
需求：./open_search 这个进程是运行go的一个服务。我们要求这个服务能在意外停止后自动重启。
安装（Centos）：
yum install python-setuptools
easy_install supervisor
测试是否安装成功：
echo_supervisord_conf
会显示以下内容，其实是一个配置模版:
; Sample supervisor config file. ; ; For more information on the config file, please see: ; http://supervisord.org/configuration.html ; ; Note: shell expansion ("~" or "$HOME") is not supported. Environment ; variables can be expanded using this syntax: "%(ENV_HOME)s".
[unix_http_server] file=/tmp/supervisor.sock ; (the path to the socket file) ;chmod=0700 ; socket file mode (default 0700) ;chown=nobody:nogroup ; socket file uid:gid owner ;username=user ; (default is no username (open server)) ;password=123 ; (default is no password (open server))
;[inet_http_server] ; inet (TCP) server disabled by default ;port=127.0.0.1:9001 ; (ip_address:port specifier, *:port for all iface) ;username=user ; (default is no username (open server)) ;password=123 ; (default is no password (open server))
[supervisord] logfile=/tmp/supervisord.log ; (main log file;default $CWD/supervisord.log) logfile_maxbytes=50MB ; (max main logfile bytes b4 rotation;default 50MB) logfile_backups=10 ; (num of main logfile rotation backups;default 10) loglevel=info ; (log level;default info; others: debug,warn,trace) pidfile=/tmp/supervisord.pid ; (supervisord pidfile;default supervisord.pid) ……
; the below section must remain in the config file for RPC ; (supervisorctl/web interface) to work, additional interfaces may be ; added by defining them in separate rpcinterface: sections [rpcinterface:supervisor] supervisor.rpcinterface_factory = supervisor.rpcinterface:make_main_rpcinterface
[supervisorctl] serverurl=unix:///tmp/supervisor.sock ; use a unix:// URL for a unix socket ;serverurl=http://127.0.0.1:9001 ; use an http:// url to specify an inet socket ;username=chris ; should be same as http_username if set ;password=123 ; should be same as http_password if set ;prompt=mysupervisor ; cmd line prompt (default "supervisor") ;history_file=~/.sc_history ; use readline history if available
; The below sample program section shows all possible program subsection values, ; create one or more ‘real’ program: sections to be able to control them under ; supervisor.
;[program:theprogramname] ;command=/bin/cat ; the program (relative uses PATH, can take args) ;process_name=%(program_name)s ; process_name expr (default %(program_name)s) ;numprocs=1 ; number of processes copies to start (def 1) ;directory=/tmp ; directory to cwd to before exec (def no cwd) ;umask=022 ; umask for process (default None) ;priority=999 ; the relative start priority (default 999) ;autostart=true ; start at supervisord start (default: true) ;autorestart=unexpected ; whether/when to restart (default: unexpected) ;startsecs=1 ; number of secs prog must stay running (def. 1) ;startretries=3 ; max # of serial start failures (default 3) ;exitcodes=0,2 ; ‘expected’ exit codes for process (default 0,2) ;stopsignal=QUIT ; signal used to kill process (default TERM) ;stopwaitsecs=10 ; max num secs to wait b4 SIGKILL (default 10) ……
;[include] ;files = relative/directory/*.ini
创建配置文件：
echo_supervisord_conf > /etc/supervisord.conf
修改配置文件：
在supervisord.conf最后增加(分号后边的表示注释，可以不写)：
[program:open_search] command=/home/s/www/fukun/gopath/src/open_search/open_search ;需要执行的命令 directory=/home/s/www/fukun/gopath/src/open_search/ ; directory to cwd to before exec (def no cwd) autostart=true ; start at supervisord start (default: true) autorestart=true ; whether/when to restart (default: unexpected) startsecs=3 ; number of secs prog must stay running (def. 1) redirect_stderr=true ; redirect proc stderr to stdout (default false) 错误输出重定向 stdout_logfile=/tmp/open_search_gorun.log ; stdout log path, NONE for none; default AUTO, log输出
（更多配置说明请参考：http://supervisord.org/configuration.html）
运行命令：
supervisord //启动supervisor
supervisorctl //打开命令行
[root@vm14211 ~]# supervisorctl redis RUNNING pid 24068, uptime 3:41:55
ctl中： help //查看命令
ctl中： status //查看状态
另外有一个坑需要注意： 如果修改了 /etc/supervisord.conf ,,需要执行 supervisorctl reload 来重新加载配置文件，否则会感觉没有生效，折腾到抓狂。。。
部分摘自：叶剑峰的BLOG
