進程管理保護的工具—Supervisor

1、supervisor簡介&功能

簡介：
supervisor 是python開發的一套進程管理的程序 ，能將一個普通的命令行進程變爲後臺daemon（保護進程），並監控進程狀態，異常退出時能自動重啓。

基本功能：

• 一、它是經過fork/exec的方式把這些被管理的進程看成supervisor的子進程來啓動，這樣只要在supervisor的配置文件中，把要管理的進程的可執行文件的路徑寫進去便可。
• 二、實現當子進程掛掉的時候，父進程能夠準確獲取子進程掛掉的信息的，能夠選擇是否本身啓動和報警。
• 三、supervisor還提供了一個功能，能夠爲supervisor或者每一個子進程，設置一個非root的user，這個user就能夠管理它對應的進程。

注：本文以centos8爲例。

2、supervisor安裝

方法1、配置好yum源後，能夠直接安裝

yum install supervisor

方法2、Debian/Ubuntu可經過apt安裝

apt-get install supervisor

方法3、pip安裝

pip install supervisor

方法4、easy_install安裝

easy_install supervisor

3、配置文件說明

3.一、supervisor.conf配置文件說明

(位置：/etc/supervisord.conf)

; Sample supervisor config file.

[unix_http_server]
file=/run/supervisor/supervisor.sock   ; (the path to the socket file) # socket對應的文件
;chmod=0700                 ; socket file mode (default 0700) # socket文件的mod，默認是0700
;chown=nobody:nogroup       ; socket file uid:gid owner # socket文件的owner，格式：uid:gid
;username=user              ; (default is no username (open server)) # 默認無用戶名
;password=123               ; (default is no password (open server)) # 默認無密碼

;[inet_http_server]         ; inet (TCP) server disabled by default # 默認關閉的tcp服務器，提供管理頁面
;port=127.0.0.1:9001        ; (ip_address:port specifier, *:port for all iface) # Web管理後臺運行的IP和端口，若是開放到公網，須要注意安全性
;username=user              ; (default is no username (open server)) # 登陸管理後臺的用戶名
;password=123               ; (default is no password (open server)) # 登陸管理後臺的密碼

[supervisord]
logfile=/var/log/supervisor/supervisord.log  ; (main log file;default $CWD/supervisord.log) # 日誌文件，默認是 $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=/run/supervisord.pid ; (supervisord pidfile;default supervisord.pid)
nodaemon=false              ; (start in foreground if true;default false)
minfds=1024                 ; (min. avail startup file descriptors;default 1024)
minprocs=200                ; (min. avail process descriptors;default 200)
;umask=022                  ; (process file creation umask;default 022)
;user=chrism                 ; (default is current user, required if root)
;identifier=supervisor       ; (supervisord identifier, default is 'supervisor')
;directory=/tmp              ; (default is not to cd during start)
;nocleanup=true              ; (don't clean up tempfiles at start;default false)
;childlogdir=/tmp            ; ('AUTO' child log dir, default $TEMP)
;environment=KEY=value       ; (key value pairs to add to environment)
;strip_ansi=false            ; (strip ansi escape codes in logs; def. false)

; 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:///run/supervisor/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=true              ; retstart at unexpected quit (default: true)
;startsecs=10                  ; 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)
;user=chrism                   ; setuid to this UNIX account to run the program
;redirect_stderr=true          ; redirect proc stderr to stdout (default false)
;stdout_logfile=/a/path        ; stdout log path, NONE for none; default AUTO
;stdout_logfile_maxbytes=1MB   ; max # logfile bytes b4 rotation (default 50MB)
;stdout_logfile_backups=10     ; # of stdout logfile backups (default 10)
;stdout_capture_maxbytes=1MB   ; number of bytes in 'capturemode' (default 0)
;stdout_events_enabled=false   ; emit events on stdout writes (default false)
;stderr_logfile=/a/path        ; stderr log path, NONE for none; default AUTO
;stderr_logfile_maxbytes=1MB   ; max # logfile bytes b4 rotation (default 50MB)
;stderr_logfile_backups=10     ; # of stderr logfile backups (default 10)
;stderr_capture_maxbytes=1MB   ; number of bytes in 'capturemode' (default 0)
;stderr_events_enabled=false   ; emit events on stderr writes (default false)
;environment=A=1,B=2           ; process environment additions (def no adds)
;serverurl=AUTO                ; override serverurl computation (childutils)

; The below sample eventlistener section shows all possible
; eventlistener subsection values, create one or more 'real'
; eventlistener: sections to be able to handle event notifications
; sent by supervisor.

;[eventlistener:theeventlistenername]
;command=/bin/eventlistener    ; 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)
;events=EVENT                  ; event notif. types to subscribe to (req'd)
;buffer_size=10                ; event buffer queue size (default 10)
;directory=/tmp                ; directory to cwd to before exec (def no cwd)
;umask=022                     ; umask for process (default None)
;priority=-1                   ; the relative start priority (default -1)
;autostart=true                ; start at supervisord start (default: true)
;autorestart=unexpected        ; restart at unexpected quit (default: unexpected)
;startsecs=10                  ; 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)
;user=chrism                   ; setuid to this UNIX account to run the program
;redirect_stderr=true          ; redirect proc stderr to stdout (default false)
;stdout_logfile=/a/path        ; stdout log path, NONE for none; default AUTO
;stdout_logfile_maxbytes=1MB   ; max # logfile bytes b4 rotation (default 50MB)
;stdout_logfile_backups=10     ; # of stdout logfile backups (default 10)
;stdout_events_enabled=false   ; emit events on stdout writes (default false)
;stderr_logfile=/a/path        ; stderr log path, NONE for none; default AUTO
;stderr_logfile_maxbytes=1MB   ; max # logfile bytes b4 rotation (default 50MB)
;stderr_logfile_backups        ; # of stderr logfile backups (default 10)
;stderr_events_enabled=false   ; emit events on stderr writes (default false)
;environment=A=1,B=2           ; process environment additions
;serverurl=AUTO                ; override serverurl computation (childutils)

; The below sample group section shows all possible group values,
; create one or more 'real' group: sections to create "heterogeneous"
; process groups.

;[group:thegroupname]
;programs=progname1,progname2  ; each refers to 'x' in [program:x] definitions
;priority=999                  ; the relative start priority (default 999)

; The [include] section can just contain the "files" setting.  This
; setting can list multiple files (separated by whitespace or
; newlines).  It can also contain wildcards.  The filenames are
; interpreted as relative to this file.  Included files *cannot*
; include files themselves.

[include]
files = supervisord.d/*.ini

3.2 、子配置文件說明

（子配置文件是咱們最須要關注的，以及常常配置的文件）

子進程配置文件,能夠添加在主配置文件的conf中，也能夠編寫一個配置文件，放在/etc/supervisor.d/目錄下，以.ini做爲擴展名（每一個進程的配置文件均可以單獨分拆也能夠把相關的腳本放一塊兒）。

如任意定義一個和腳本相關的項目名稱的選項組（/etc/supervisord.d/test.ini）：

例子:

#項目名
[program:test]
#腳本目錄
directory=/opt/bin
#腳本執行命令
command=/usr/bin/python /opt/bin/test.py

#supervisor啓動的時候是否隨着同時啓動，默認True
autostart=true
#當程序exit的時候，這個program不會自動重啓,默認unexpected，設置子進程掛掉後自動重啓的狀況，有三個選項，false,unexpected和true。若是爲false的時候，不管什麼狀況下，都不會被從新啓動，若是爲unexpected，只有當進程的退出碼不在下面的exitcodes裏面定義的
autorestart=false
#這個選項是子進程啓動多少秒以後，此時狀態若是是running，則咱們認爲啓動成功了。默認值爲1
startsecs=1

#腳本運行的用戶身份 
user = www

#日誌輸出 
stderr_logfile=/tmp/test_stderr.log 
stdout_logfile=/tmp/test_stdout.log 
#把stderr重定向到stdout，默認 false
redirect_stderr = true
#stdout日誌文件大小，默認 50MB
stdout_logfile_maxbytes = 50M
#stdout日誌文件備份數
stdout_logfile_backups = 20

4、supervisor經常使用命令

supervisord -c /etc/supervisord.conf #啓動supervisor服務命令
supervisorctl status                #查看全部進程的狀態
supervisorctl stop test             #中止設置的test進程
supervisorctl start test            #啓動設置的test進程
supervisorctl restart test          #從新啓動設置的test進程
supervisorctl update ：             #配置文件修改後可使用該命令加載新的配置
supervisorctl reload:               #從新啓動配置中的全部程序

常見問題集錦

一、unix:///var/run/supervisor/supervisor.sock no such file

問題描述：安裝好supervisor沒有開啓服務直接使用supervisorctl報的錯
解決辦法：supervisord -c /etc/supervisord.conf 

二、command中指定的進程已經起來，但supervisor還不斷重啓

問題描述：command中啓動方式爲後臺啓動，致使識別不到pid，而後不斷重啓，
解決辦法：supervisor沒法檢測後臺啓動進程的pid，而supervisor自己就是後臺啓動守護進程，所以不用擔憂這個

三、啓動了多個supervisord服務，致使沒法正常關閉服務

問題描述：在運行supervisord -c /etc/supervisord.conf 以前，我直接運行過supervisord -c /etc/supervisord.d/xx.ini，致使有些進程被多個superviord管理，沒法正常關閉進程。
解決辦法：使用ps -ef | grep supervisord 查看全部啓動過的supervisord服務，kill相關的進程。

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