chkconfig命令是Red Hat遵循GPL规则所开发的程序，它可以查询操作系统在每一个执行等级中会执行哪些系统服务，其中包括各类常驻服务。chkconfig主要用于查看、设置、更新系统服务的运行级信息，chkconfig并不是立即自动禁止或激活一个服务，它只是简单的改变了符号连接。
命令分类：系统设置
chkconfig语法格式
chkconfig [--list] [--type <类型>] [名称] chkconfig --add <名称> chkconfig --del <名称> chkconfig --override <名称> chkconfig [--level <级别>] [--type <类型>] <名称>
执行chkconfig命令时，如果不指定运行参数，则显示命令用法。
如果指定服务名，则检查这个服务是否在当前运行级启动，返回true或false，分别表示是或否。
chkconfig在没有参数运行时，显示用法。如果加上服务名，那么就检查这个服务是否在当前运行级启动。如果是，返回true，否则返回false。如果在服务名后面指定了on、off或reset，那么chkconfig会改变指定服务的启动信息。on、off和reset分别表示指服务被启动、停止和重置服务的启动信息。on和off开关，系统默认只对运行级3，4，5有效，但reset对所有运行级有效。
参数
-
--add：增加指定的系统服务，以使此服务可以被chkconfig管理，并同时在系统启动的描述文件内增加相关数据。 -
--del：删除指定的系统服务，使此服务不再被chkconfig指令管理，并同时在系统启动的描述文件内删除相关数据。 -
--level：等级代号，指定读取系统服务时要在哪一个执行等级中开启或关毕。-
0级：表示关机 -
1级：单用户模式 -
2级：无网络连接的多用户命令行模式 -
3级：有网络连接的多用户命令行模式 -
4级：不可用 -
5级：带图形界面的多用户模式 -
6级：重新启动
-
使用--level参数指定运行级时，不一定是当前运行级别，而是可以指定任一运行级。对于每个运行级，只能有一个启动脚本或者停止脚本。当切换运行级时，init不会重新启动已经启动的服务，也不会再次停止已经停止的服务。
示例
一些常用的chkconfig使用示例：
chkconfig --list #查看所有系统服务的启动情况 chkconfig --add httpd #增加httpd服务 chkconfig --del httpd #删除httpd服务 chkconfig --level httpd 2345 on #设置httpd在运行级别为2、3、4、5时，都是开启的状态 chkconfig --list mysqld #查看 mysqld服务设置情况 chkconfig --level 35 mysqld on #设置mysqld在运行级别为3、5时开机运行服务 chkconfig mysqld on #设置mysqld在各个运行级都为开启状态，运行级包括2、3、4、5
使用chkconfig命令将mysql添加到开机启动项，增加一个系统服务包含以下三个步骤：
-
在
/etc/ini.d/目录下增加服务脚本 -
chkconfig --add 服务名增加服务名 -
chkconfig --level设置运行级别
1. 在/etc/ini.d/目录下增加mysqld脚本：
#!/bin/sh # Copyright Abandoned 1996 TCX DataKonsult AB & Monty Program KB & Detron HB # This file is public domain and comes with NO WARRANTY of any kind # MySQL daemon start/stop script. # Usually this is put in /etc/init.d (at least on machines SYSV R4 based # systems) and linked to /etc/rc3.d/S99mysql and /etc/rc0.d/K01mysql. # When this is done the mysql server will be started when the machine is # started and shut down when the systems goes down. # Comments to support chkconfig on RedHat Linux # chkconfig: 2345 64 36 # description: A very fast and reliable SQL database engine. # Comments to support LSB init script conventions ### BEGIN INIT INFO # Provides: mysql # Required-Start: $local_fs $network $remote_fs # Should-Start: ypbind nscd ldap ntpd xntpd # Required-Stop: $local_fs $network $remote_fs # Default-Start: 2 3 4 5 # Default-Stop: 0 1 6 # Short-Description: start and stop MySQL # Description: MySQL is a very fast and reliable SQL database engine. ### END INIT INFO # If you install MySQL on some other places than /alidata/server/mysql, then you # have to do one of the following things for this script to work: # # - Run this script from within the MySQL installation directory # - Create a /etc/my.cnf file with the following information: # [mysqld] # basedir=# - Add the above to any other configuration file (for example ~/.my.ini) # and copy my_print_defaults to /usr/bin # - Add the path to the mysql-installation-directory to the basedir variable # below. # # If you want to affect other MySQL variables, you should make your changes # in the /etc/my.cnf, ~/.my.cnf or other MySQL configuration files. # If you change base dir, you must also change datadir. These may get # overwritten by settings in the MySQL configuration files. basedir= datadir= # Default value, in seconds, afterwhich the script should timeout waiting # for server start. # Value here is overriden by value in my.cnf. # 0 means don't wait at all # Negative numbers mean to wait indefinitely service_startup_timeout=900 # The following variables are only set for letting mysql.server find things. # Set some defaults pid_file= server_pid_file= use_mysqld_safe=1 user=mysql if test -z "$basedir" then basedir=/alidata/server/mysql bindir=/alidata/server/mysql/bin if test -z "$datadir" then datadir=/alidata/server/mysql/var fi sbindir=/alidata/server/mysql/sbin libexecdir=/alidata/server/mysql/libexec else bindir="$basedir/bin" if test -z "$datadir" then datadir="$basedir/data" fi sbindir="$basedir/sbin" libexecdir="$basedir/libexec" fi # datadir_set is used to determine if datadir was set (and so should be # *not* set inside of the --basedir= handler.) datadir_set= # # Use LSB init script functions for printing messages, if possible # lsb_functions="/lib/lsb/init-functions" if test -f $lsb_functions ; then . $lsb_functions else log_success_msg() { echo " SUCCESS! $@" } log_failure_msg() { echo " ERROR! $@" } fi PATH=/sbin:/usr/sbin:/bin:/usr/bin:$basedir/bin export PATH mode=$1 # start or stop shift other_args="$*" # uncommon, but needed when called from an RPM upgrade action # Expected: "--skip-networking --skip-grant-tables" # They are not checked here, intentionally, as it is the resposibility # of the "spec" file author to give correct arguments only. case `echo "testing\c"`,`echo -n testing` in *c*,-n*) echo_n= echo_c= ;; *c*,*) echo_n=-n echo_c= ;; *) echo_n= echo_c='\c' ;; esac parse_server_arguments() { for arg do case "$arg" in --basedir=*) basedir=`echo "$arg" | sed -e 's/^[^=]*=//'` bindir="$basedir/bin" if test -z "$datadir_set"; then datadir="$basedir/data" fi sbindir="$basedir/sbin" libexecdir="$basedir/libexec" ;; --datadir=*) datadir=`echo "$arg" | sed -e 's/^[^=]*=//'` datadir_set=1 ;; --user=*) user=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --pid-file=*) server_pid_file=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --service-startup-timeout=*) service_startup_timeout=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --use-mysqld_safe) use_mysqld_safe=1;; --use-manager) use_mysqld_safe=0;; esac done } parse_manager_arguments() { for arg do case "$arg" in --pid-file=*) pid_file=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --user=*) user=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; esac done } wait_for_pid () { verb="$1" manager_pid="$2" # process ID of the program operating on the pid-file i=0 avoid_race_condition="by checking again" while test $i -ne $service_startup_timeout ; do case "$verb" in 'created') # wait for a PID-file to pop into existence. test -s $pid_file && i='' && break ;; 'removed') # wait for this PID-file to disappear test ! -s $pid_file && i='' && break ;; *) echo "wait_for_pid () usage: wait_for_pid created|removed manager_pid" exit 1 ;; esac # if manager isn't running, then pid-file will never be updated if test -n "$manager_pid"; then if kill -0 "$manager_pid" 2>/dev/null; then : # the manager still runs else # The manager may have exited between the last pid-file check and now. if test -n "$avoid_race_condition"; then avoid_race_condition="" continue # Check again. fi # there's nothing that will affect the file. log_failure_msg "Manager of pid-file quit without updating file." return 1 # not waiting any more. fi fi echo $echo_n ".$echo_c" i=`expr $i + 1` sleep 1 done if test -z "$i" ; then log_success_msg return 0 else log_failure_msg return 1 fi } # Get arguments from the my.cnf file, # the only group, which is read from now on is [mysqld] if test -x ./bin/my_print_defaults then print_defaults="./bin/my_print_defaults" elif test -x $bindir/my_print_defaults then print_defaults="$bindir/my_print_defaults" elif test -x $bindir/mysql_print_defaults then print_defaults="$bindir/mysql_print_defaults" else # Try to find basedir in /etc/my.cnf conf=/etc/my.cnf print_defaults= if test -r $conf then subpat='^[^=]*basedir[^=]*=\(.*\)$' dirs=`sed -e "/$subpat/!d" -e 's//\1/' $conf` for d in $dirs do d=`echo $d | sed -e 's/[ ]//g'` if test -x "$d/bin/my_print_defaults" then print_defaults="$d/bin/my_print_defaults" break fi if test -x "$d/bin/mysql_print_defaults" then print_defaults="$d/bin/mysql_print_defaults" break fi done fi # Hope it's in the PATH ... but I doubt it test -z "$print_defaults" && print_defaults="my_print_defaults" fi # # Read defaults file from 'basedir'. If there is no defaults file there # check if it's in the old (depricated) place (datadir) and read it from there # extra_args="" if test -r "$basedir/my.cnf" then extra_args="-e $basedir/my.cnf" else if test -r "$datadir/my.cnf" then extra_args="-e $datadir/my.cnf" fi fi parse_server_arguments `$print_defaults $extra_args mysqld server mysql_server mysql.server` # Look for the pidfile parse_manager_arguments `$print_defaults $extra_args manager` # # Set pid file if not given # if test -z "$pid_file" then pid_file=$datadir/mysqlmanager-`/bin/hostname`.pid else case "$pid_file" in /* ) ;; * ) pid_file="$datadir/$pid_file" ;; esac fi if test -z "$server_pid_file" then server_pid_file=$datadir/`/bin/hostname`.pid else case "$server_pid_file" in /* ) ;; * ) server_pid_file="$datadir/$server_pid_file" ;; esac fi case "$mode" in 'start') # Start daemon # Safeguard (relative paths, core dumps..) cd $basedir manager=$bindir/mysqlmanager if test -x $libexecdir/mysqlmanager then manager=$libexecdir/mysqlmanager elif test -x $sbindir/mysqlmanager then manager=$sbindir/mysqlmanager fi echo $echo_n "Starting MySQL" if test -x $manager -a "$use_mysqld_safe" = "0" then if test -n "$other_args" then log_failure_msg "MySQL manager does not support options '$other_args'" exit 1 fi # Give extra arguments to mysqld with the my.cnf file. This script may # be overwritten at next upgrade. "$manager" \ --mysqld-safe-compatible \ --user="$user" \ --pid-file="$pid_file" >/dev/null 2>&1 & wait_for_pid created $!; return_value=$? # Make lock for RedHat / SuSE if test -w /var/lock/subsys then touch /var/lock/subsys/mysqlmanager fi exit $return_value elif test -x $bindir/mysqld_safe then # Give extra arguments to mysqld with the my.cnf file. This script # may be overwritten at next upgrade. pid_file=$server_pid_file $bindir/mysqld_safe --datadir=$datadir --pid-file=$server_pid_file $other_args >/dev/null 2>&1 & wait_for_pid created $!; return_value=$? # Make lock for RedHat / SuSE if test -w /var/lock/subsys then touch /var/lock/subsys/mysql fi exit $return_value else log_failure_msg "Couldn't find MySQL manager ($manager) or server ($bindir/mysqld_safe)" fi ;; 'stop') # Stop daemon. We use a signal here to avoid having to know the # root password. # The RedHat / SuSE lock directory to remove lock_dir=/var/lock/subsys/mysqlmanager # If the manager pid_file doesn't exist, try the server's if test ! -s "$pid_file" then pid_file=$server_pid_file lock_dir=/var/lock/subsys/mysql fi if test -s "$pid_file" then mysqlmanager_pid=`cat $pid_file` if (kill -0 $mysqlmanager_pid 2>/dev/null) then echo $echo_n "Shutting down MySQL" kill $mysqlmanager_pid # mysqlmanager should remove the pid_file when it exits, so wait for it. wait_for_pid removed "$mysqlmanager_pid"; return_value=$? else log_failure_msg "MySQL manager or server process #$mysqlmanager_pid is not running!" rm $pid_file fi # delete lock for RedHat / SuSE if test -f $lock_dir then rm -f $lock_dir fi exit $return_value else log_failure_msg "MySQL manager or server PID file could not be found!" fi ;; 'restart') # Stop the service and regardless of whether it was # running or not, start it again. if $0 stop $other_args; then $0 start $other_args else log_failure_msg "Failed to stop running server, so refusing to try to start." exit 1 fi ;; 'reload'|'force-reload') if test -s "$server_pid_file" ; then read mysqld_pid < $server_pid_file kill -HUP $mysqld_pid && log_success_msg "Reloading service MySQL" touch $server_pid_file else log_failure_msg "MySQL PID file could not be found!" exit 1 fi ;; 'status') # First, check to see if pid file exists if test -s "$server_pid_file" ; then read mysqld_pid < $server_pid_file if kill -0 $mysqld_pid 2>/dev/null ; then log_success_msg "MySQL running ($mysqld_pid)" exit 0 else log_failure_msg "MySQL is not running, but PID file exists" exit 1 fi else # Try to find appropriate mysqld process mysqld_pid=`pidof $libexecdir/mysqld` if test -z $mysqld_pid ; then if test "$use_mysqld_safe" = "0" ; then lockfile=/var/lock/subsys/mysqlmanager else lockfile=/var/lock/subsys/mysql fi if test -f $lockfile ; then log_failure_msg "MySQL is not running, but lock exists" exit 2 fi log_failure_msg "MySQL is not running" exit 3 else log_failure_msg "MySQL is running but PID file could not be found" exit 4 fi fi ;; *) # usage echo "Usage: $0 {start|stop|restart|reload|force-reload|status} [ MySQL server options ]" exit 1 ;; esac exit 0
在以上脚本的注释信息中，有以下两行注释：
# chkconfig: 2345 64 36 # description: A very fast and reliable SQL database engine.
其中chkconfig: 2345 64 36表示缺省启动时运行级以及启动和停止的优先级，如果某服务缺省不在任何运行级启动，那么使用- 代替运行级。而description表示描述信息，可以使用\跨行注释
2. 添加mysqld服务：
chkconfig --add mysqld
3. 设置mysqld的运行级别为2、3、4、5：
chkconfig --level 2345 mysqld on