Tệp rc.status trong linux

Question

Tôi đang tạo một dịch vụ linux, trong tệp bộ xương, nó được đề cập rằng chúng ta cần chạy các lệnh rc khác nhau (rc-status, rc_reset) để cập nhật trạng thái dịch vụ. Điều này thực sự có ý nghĩa gì. Tôi đã googled nó nhưng không thể tìm thấy nhiều chi tiết. Ai đó có thể giúp tôi

Answer 1

Các lệnh từ rc.status thực sự SuSe cụ thể tôi nghĩ. AFAICT họ xử lý hai thứ: đầu ra cho người dùng và trạng thái trả về cuối cùng của tập lệnh. rc_status kiểm tra xem lệnh trước đó (tức là khởi động/khởi động lại/dừng dịch vụ) được thực hiện thành công và đặt "giá trị trạng thái", là giá trị trả về được trả về bởi rc_exit (mà bạn đặt ở cuối tập lệnh init.d) . Source

Bạn có thể ghi tập lệnh shell mà không cần đến chúng, nhưng tôi cho rằng chúng giúp đảm bảo rằng tập lệnh của bạn tuân thủ các yêu cầu của LSB và kết hợp tốt với các tập lệnh hệ thống khác. Tôi đặt cược hầu hết điều này thực sự là tài liệu trong tập tin /etc/rc.status, mặc dù. Tôi chỉ không có một hộp suse tiện dụng.

Answer 2

Bạn cần tập lệnh trình bao để dừng/bắt đầu/khởi động lại dịch vụ của mình và đưa ra trạng thái của nó. Chúng thường được gọi là các tập lệnh rc. Có một cái nhìn trong thư mục /etc/init.d để xem một số ví dụ - /etc/init.d/klogd khá đơn giản.

Lý do chúng ở trong init.d là vì chúng cũng cần được chạy tự động khi khởi động để khôi phục dịch vụ.

Mỗi biến thể Linux có xu hướng được một chút khác nhau về cách khởi động lên công trình nhưng hệ thống Debian là khá điển hình vì nó là cơ sở cho nhiều bản phân phối khác - xem Debian Boot Up Manager

Answer 3

Dưới đây là những ý kiến ​​chặn từ /etc/init.d/skeleton từ SUSE Linux Enterprise Server 11 SP3:

#!/bin/sh 
# 
#  Template SUSE system startup script for example service/daemon FOO 
#  Copyright (C) 1995--2005 Kurt Garloff, SUSE/Novell Inc. 
#   
#  This library is free software; you can redistribute it and/or modify it 
#  under the terms of the GNU Lesser General Public License as published by 
#  the Free Software Foundation; either version 2.1 of the License, or (at 
#  your option) any later version. 
#     
#  This library is distributed in the hope that it will be useful, but 
#  WITHOUT ANY WARRANTY; without even the implied warranty of 
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
#  Lesser General Public License for more details. 
#  
#  You should have received a copy of the GNU Lesser General Public 
#  License along with this library; if not, write to the Free Software 
#  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, 
#  USA. 
# 
# /etc/init.d/FOO 
# and its symbolic link 
# /(usr/)sbin/rcFOO 
# 
# Template system startup script for some example service/daemon FOO 
# 
# LSB compatible service control script; see http://www.linuxbase.org/spec/ 
# 
# Note: This template uses functions rc_XXX defined in /etc/rc.status on 
# UnitedLinux/SUSE/Novell based Linux distributions. If you want to base your 
# script on this template and ensure that it works on non UL based LSB 
# compliant Linux distributions, you either have to provide the rc.status 
# functions from UL or change the script to work without them. 
# See skeleton.compat for a template that works with other distros as well. 
# 
### BEGIN INIT INFO 
# Provides:   FOO 
# Required-Start: $syslog $remote_fs 
# Should-Start:  $time ypbind smtp 
# Required-Stop:  $syslog $remote_fs 
# Should-Stop:  ypbind smtp 
# Default-Start:  3 5 
# Default-Stop:  0 1 2 6 
# Short-Description: FOO XYZ daemon providing ZYX 
# Description:  Start FOO to allow XY and provide YZ 
# continued on second line by '#<TAB>' 
# should contain enough info for the runlevel editor 
# to give admin some idea what this service does and 
# what it's needed for ... 
# (The Short-Description should already be a good hint.) 
### END INIT INFO 
# 
# Any extensions to the keywords given above should be preceeded by 
# X-VendorTag- (X-UnitedLinux- X-SuSE- for us) according to LSB. 
# 
# Notes on Required-Start/Should-Start: 
# * There are two different issues that are solved by Required-Start 
# and Should-Start 
# (a) Hard dependencies: This is used by the runlevel editor to determine 
#  which services absolutely need to be started to make the start of 
#  this service make sense. Example: nfsserver should have 
#  Required-Start: $portmap 
#  Also, required services are started before the dependent ones. 
#  The runlevel editor will warn about such missing hard dependencies 
#  and suggest enabling. During system startup, you may expect an error, 
#  if the dependency is not fulfilled. 
# (b) Specifying the init script ordering, not real (hard) dependencies. 
#  This is needed by insserv to determine which service should be 
#  started first (and at a later stage what services can be started 
#  in parallel). The tag Should-Start: is used for this. 
#  It tells, that if a service is available, it should be started 
#  before. If not, never mind. 
# * When specifying hard dependencies or ordering requirements, you can 
# use names of services (contents of their Provides: section) 
# or pseudo names starting with a $. The following ones are available 
# according to LSB (1.1): 
# $local_fs  all local file systems are mounted 
#    (most services should need this!) 
# $remote_fs  all remote file systems are mounted 
#    (note that /usr may be remote, so 
#    many services should Require this!) 
# $syslog   system logging facility up 
# $network  low level networking (eth card, ...) 
# $named   hostname resolution available 
# $netdaemons  all network daemons are running 
# The $netdaemons pseudo service has been removed in LSB 1.2. 
# For now, we still offer it for backward compatibility. 
# These are new (LSB 1.2): 
# $time   the system time has been set correctly 
# $portmap  SunRPC portmapping service available 
# UnitedLinux extensions: 
# $ALL   indicates that a script should be inserted 
#    at the end 
# * The services specified in the stop tags 
# (Required-Stop/Should-Stop) 
# specify which services need to be still running when this service 
# is shut down. Often the entries there are just copies or a subset 
# from the respective start tag. 
# * Should-Start/Stop are now part of LSB as of 2.0, 
# formerly SUSE/Unitedlinux used X-UnitedLinux-Should-Start/-Stop. 
# insserv does support both variants. 
# * X-UnitedLinux-Default-Enabled: yes/no is used at installation time 
# (%fillup_and_insserv macro in %post of many RPMs) to specify whether 
# a startup script should default to be enabled after installation. 
# It's not used by insserv. 
# 
# Note on runlevels: 
# 0 - halt/poweroff    6 - reboot 
# 1 - single user   2 - multiuser without network exported 
# 3 - multiuser w/ network (text mode) 5 - multiuser w/ network and X11 (xdm) 
# 
# Note on script names: 
# http://www.linuxbase.org/spec/refspecs/LSB_1.3.0/gLSB/gLSB/scrptnames.html 
# A registry has been set up to manage the init script namespace. 
# http://www.lanana.org/ 
# Please use the names already registered or register one or use a 
# vendor prefix. 
#... 
# Source LSB init functions 
# providing start_daemon, killproc, pidofproc, 
# log_success_msg, log_failure_msg and log_warning_msg. 
# This is currently not used by UnitedLinux based distributions and 
# not needed for init scripts for UnitedLinux only. If it is used, 
# the functions from rc.status should not be sourced or used. 
#. /lib/lsb/init-functions 
# 
# Shell functions sourced from /etc/rc.status: 
#  rc_check   check and set local and overall rc status 
#  rc_status  check and set local and overall rc status 
#  rc_status -v  be verbose in local rc status and clear it afterwards 
#  rc_status -v -r ditto and clear both the local and overall rc status 
#  rc_status -s  display "skipped" and exit with status 3 
#  rc_status -u  display "unused" and exit with status 3 
#  rc_failed  set local and overall rc status to failed 
#  rc_failed <num> set local and overall rc status to <num> 
#  rc_reset   clear both the local and overall rc status 
#  rc_exit   exit appropriate to overall rc status 
#  rc_active  checks whether a service is activated by symlinks 
#... 
# 
# Return values acc. to LSB for all commands but status: 
# 0 - success 
# 1  - generic or unspecified error 
# 2  - invalid or excess argument(s) 
# 3  - unimplemented feature (e.g. "reload") 
# 4  - user had insufficient privileges 
# 5  - program is not installed 
# 6  - program is not configured 
# 7  - program is not running 
# 8--199 - reserved (8--99 LSB, 100--149 distrib, 150--199 appl) 
# 
# Note that starting an already running service, stopping 
# or restarting a not-running service as well as the restart 
# with force-reload (in case signaling is not supported) are 
# considered a success. 
#... 
## Check status with checkproc(8), if process is running 
## checkproc will return with exit status 0. 
# 
# Return value is slightly different for the status command: 
# 0 - service up and running 
# 1 - service dead, but /var/run/ pid file exists 
# 2 - service dead, but /var/lock/ lock file exists 
# 3 - service not running (unused) 
# 4 - service status unknown :-(
# 5--199 reserved (5--99 LSB, 100--149 distro, 150--199 appl.) 

Dưới đây là những ý kiến ​​khối từ /etc/rc.status từ SUSE Linux Enterprise Server 11 SP3:

# /etc/rc.status 
# vim: syntax=sh 
# Definition of boot script return messages 
# 
# The bootscripts should use the variables rc_done and rc_failed to 
# report whether they failed or succeeded. See /etc/init.d/skeleton for 
# an example how the shell functions rc_status and rc_reset are used. 
# 
# These functions make use of the variables rc_done and rc_failed; 
# rc_done_up and rc_failed_up are the same as rc_done and rc_failed 
# but contain a terminal code to move up one line before the output 
# of the actual string. (This is particularly useful when the script 
# starts a daemon which produces user output with a newline character) 
# 
# The variable rc_reset is used by the master resource control script 
# /etc/init.d/rc to turn off all attributes and switch to the standard 
# character set. 
# 
# \033   ascii ESCape 
# \033[<NUM>G move to column <NUM> (linux console, xterm, not vt100) 
# \033[<NUM>C move <NUM> columns forward but only upto last column 
# \033[<NUM>D move <NUM> columns backward but only upto first column 
# \033[<NUM>A move <NUM> rows up 
# \033[<NUM>B move <NUM> rows down 
# \033[1m  switch on bold 
# \033[31m  switch on red 
# \033[32m  switch on green 
# \033[33m  switch on yellow 
# \033[m  switch off color/bold 
# \017   exit alternate mode (xterm, vt100, linux console) 
# \033[10m  exit alternate mode (linux console) 
# \015   carriage return (without newline)