MySQL server sysv script

上一篇简单介绍了MariaDB 10 with Galera在Docker中使用yum安装.

安装完后, 简单介绍一下systemv的控制脚本.

包含一些变量, 可能需要手工配置.

1. 主要包含

    mysql软件的安装目录, 

    数据库的数据目录.

2. 启动数据库后的PID文件放哪里, 

    启动数据库的超时机制,

3. 是否使用mysqld_safe启动数据库

[root@mariadb my.cnf.d]# mysqld_safe --help      
Usage: /usr/bin/mysqld_safe [OPTIONS]
  --no-defaults              Don't read the system defaults file
  --core-file-size=LIMIT     Limit core files to the specified size
  --defaults-file=FILE       Use the specified defaults file
  --defaults-extra-file=FILE Also use defaults from the specified file
  --ledir=DIRECTORY          Look for mysqld in the specified directory
  --open-files-limit=LIMIT   Limit the number of open files
  --crash-script=FILE        Script to call when mysqld crashes
  --timezone=TZ              Set the system timezone
  --malloc-lib=LIB           Preload shared library LIB if available
  --mysqld=FILE              Use the specified file as mysqld
  --mysqld-version=VERSION   Use "mysqld-VERSION" as mysqld
  --nice=NICE                Set the scheduling priority of mysqld
  --no-auto-restart          Exit after starting mysqld
  --nowatch                  Exit after starting mysqld
  --plugin-dir=DIR           Plugins are under DIR or DIR/VERSION, if
                             VERSION is given
  --skip-kill-mysqld         Don't try to kill stray mysqld processes
  --syslog                   Log messages to syslog with 'logger'
  --skip-syslog              Log messages to error log (default)
  --syslog-tag=TAG           Pass -t "mysqld-TAG" to 'logger'
  --flush-caches             Flush and purge buffers/caches before
                             starting the server
  --numa-interleave          Run mysqld with its memory interleaved
                             on all NUMA nodes

All other options are passed to the mysqld program.

4. 额外配置文件, 优先使用$basedir/my.cnf, 然后使用$datadir/my.cnf.

建议将配置文件放在数据目录, PostgreSQL就是这么干的.

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


mysql.server supports the following options.

• --basedir=path
  • The path to the MariaDB installation directory.
• --datadir=path
  • The path to the MariaDB data directory.
• --pid-file=file_name
  • The path name of the file in which the server should write its process ID.
• --service-startup-timeout=file_name
  • How long in seconds to wait for confirmation of server startup. If the server does not start within this time, mysql.server exits with an error. The default value is 900. A value of 0 means not to wait at all for startup. Negative values mean to wait forever (no timeout). This option was added in MySQL 5.0.40. Before that, a value of 900 is always used.
• --use-mysqld_safe
  • Use mysqld_safe to start the server. This is the default. This option was added in MySQL 5.0.4.
• --use-manager
  • Use Instance Manager to start the server. This option was added in MySQL 5.0.4.
• --user=user_name
  • The login user name to use for running mysqld. This option was added in MySQL 5.0.4.

脚本内容如下 : 

[root@mariadb /]# cat /etc/init.d/mysql    

#!/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 /usr, 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=<path-to-mysql-installation-directory>
# - 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
startup_sleep=1

# Lock directory for RedHat / SuSE.
lockdir='/var/lock/subsys'
lock_file_path="$lockdir/mysql"

# The following variables are only set for letting mysql.server find things.

# Set some defaults
mysqld_pid_file_path=
if test -z "$basedir"
then
  basedir=/usr
  bindir=/usr/bin
  if test -z "$datadir"
  then
    datadir=/var/lib/mysql
  fi
  sbindir=/usr/sbin
  libexecdir=/usr/sbin
else
  bindir="$basedir/bin"
  if test -z "$datadir"
  then
    datadir="$basedir/data"
  fi
  sbindir="$basedir/sbin"
  if test -f "$basedir/bin/mysqld"
  then
    libexecdir="$basedir/bin"
  else
    libexecdir="$basedir/libexec"
  fi
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

[ $# -ge 1 ] && 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"
                    if test -f "$basedir/bin/mysqld"
                    then
                      libexecdir="$basedir/bin"
                    else
                      libexecdir="$basedir/libexec"
                    fi
                    libexecdir="$basedir/libexec"
        ;;
      --datadir=*)  datadir=`echo "$arg" | sed -e 's/^[^=]*=//'`
                    datadir_set=1
        ;;
      --pid-file=*) mysqld_pid_file_path=`echo "$arg" | sed -e 's/^[^=]*=//'` ;;
      --service-startup-timeout=*) service_startup_timeout=`echo "$arg" | sed -e 's/^[^=]*=//'` ;;
    esac
  done
}

# 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`

# wait for the pid file to disappear
wait_for_gone () {
  pid="$1"           # process ID of the program operating on the pid-file
  pid_file_path="$2" # path to the PID file.

  i=0
  crash_protection="by checking again"

  while test $i -ne $service_startup_timeout ; do

    if kill -0 "$pid" 2>/dev/null; then
      :  # the server still runs
    else
      if test ! -s "$pid_file_path"; then
        # no server process and no pid-file? great, we're done!
        log_success_msg
        return 0
      fi

      # pid-file exists, the server process doesn't.
      # it must've crashed, and mysqld_safe will restart it
      if test -n "$crash_protection"; then
        crash_protection=""
        sleep 5
        continue  # Check again.
      fi

      # Cannot help it
      log_failure_msg "The server quit without updating PID file ($pid_file_path)."
      return 1  # not waiting any more.
    fi

    echo $echo_n ".$echo_c"
    i=`expr $i + 1`
    sleep 1

  done

  log_failure_msg
  return 1
}

wait_for_ready () {

  sst_progress_file=$datadir/sst_in_progress

  i=0
  while test $i -ne $service_startup_timeout ; do

    if $bindir/mysqladmin ping >/dev/null 2>&1; then
      log_success_msg
      return 0
    elif kill -0 $! 2>/dev/null ; then
      :  # mysqld_safe is still running
    else
      # mysqld_safe is no longer running, abort the wait loop
      break
    fi

    if test -e $sst_progress_file && [ $startup_sleep -ne 10 ];then
      echo $echo_n "SST in progress, setting sleep higher"
      startup_sleep=10
    fi

    echo $echo_n ".$echo_c"
    i=`expr $i + 1`
    sleep $startup_sleep

  done

  log_failure_msg
  return 1
}
#
# Set pid file if not given
#
if test -z "$mysqld_pid_file_path"
then
  mysqld_pid_file_path=$datadir/`hostname`.pid
else
  case "$mysqld_pid_file_path" in
    /* ) ;;
    * )  mysqld_pid_file_path="$datadir/$mysqld_pid_file_path" ;;
  esac
fi

# source other config files
[ -f /etc/default/mysql ] && . /etc/default/mysql
[ -f /etc/sysconfig/mysql ] && . /etc/sysconfig/mysql
[ -f /etc/conf.d/mysql ] && . /etc/conf.d/mysql

case "$mode" in
  'start')
    # Start daemon

    # Safeguard (relative paths, core dumps..)
    cd $basedir

    echo $echo_n "Starting MySQL"
    if test -x $bindir/mysqld_safe
    then
      # Give extra arguments to mysqld with the my.cnf file. This script
      # may be overwritten at next upgrade.
      $bindir/mysqld_safe --datadir="$datadir" --pid-file="$mysqld_pid_file_path" $other_args >/dev/null 2>&1 &
      wait_for_ready; return_value=$?

      # Make lock for RedHat / SuSE
      if test -w "$lockdir"
      then
        touch "$lock_file_path"
      fi

      exit $return_value
    else
      log_failure_msg "Couldn't find MySQL server ($bindir/mysqld_safe)"
    fi
    ;;

  'stop')
    # Stop daemon. We use a signal here to avoid having to know the
    # root password.

    if test -s "$mysqld_pid_file_path"
    then
      mysqld_pid=`cat "$mysqld_pid_file_path"`

      if (kill -0 $mysqld_pid 2>/dev/null)
      then
        echo $echo_n "Shutting down MySQL"
        kill $mysqld_pid
        # mysqld should remove the pid file when it exits, so wait for it.
        wait_for_gone $mysqld_pid "$mysqld_pid_file_path"; return_value=$?
      else
        log_failure_msg "MySQL server process #$mysqld_pid is not running!"
        rm "$mysqld_pid_file_path"
      fi

      # Delete lock for RedHat / SuSE
      if test -f "$lock_file_path"
      then
        rm -f "$lock_file_path"
      fi
      exit $return_value
    else
      log_failure_msg "MySQL 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
      if ! $0 start $other_args; then
        log_failure_msg "Failed to restart server."
        exit 1
      fi
    else
      log_failure_msg "Failed to stop running server, so refusing to try to start."
      exit 1
    fi
    ;;

  'reload'|'force-reload')
    if test -s "$mysqld_pid_file_path" ; then
      read mysqld_pid <  "$mysqld_pid_file_path"
      kill -HUP $mysqld_pid && log_success_msg "Reloading service MySQL"
      touch "$mysqld_pid_file_path"
    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 "$mysqld_pid_file_path" ; then 
      read mysqld_pid < "$mysqld_pid_file_path"
      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`

      # test if multiple pids exist
      pid_count=`echo $mysqld_pid | wc -w`
      if test $pid_count -gt 1 ; then
        log_failure_msg "Multiple MySQL running but PID file could not be found ($mysqld_pid)"
        exit 5
      elif test -z $mysqld_pid ; then 
        if test -f "$lock_file_path" ; then 
          log_failure_msg "MySQL is not running, but lock file ($lock_file_path) 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
    ;;
  'configtest')
    # Safeguard (relative paths, core dumps..)
    cd $basedir
    echo $echo_n "Testing MySQL configuration syntax"
    daemon=$bindir/mysqld
    if test -x $libexecdir/mysqld
    then
      daemon=$libexecdir/mysqld
    elif test -x $sbindir/mysqld
    then
      daemon=$sbindir/mysqld
    elif test -x `which mysqld`
    then
      daemon=`which mysqld`
    else
      log_failure_msg "Unable to locate the mysqld binary!"
      exit 1
    fi
    help_out=`$daemon --help 2>&1`; r=$?
    if test "$r" != 0 ; then
      log_failure_msg "$help_out"
      log_failure_msg "There are syntax errors in the server configuration. Please fix them!"
    else
      log_success_msg "Syntax OK"
    fi
    exit $r
    ;;
  'bootstrap')
      # Bootstrap the cluster, start the first node
      # that initiate the cluster
      echo $echo_n "Bootstrapping the cluster"
      $0 start $other_args --wsrep-new-cluster
      ;;
  *)
      # usage
      basename=`basename "$0"`
      echo "Usage: $basename  {start|stop|restart|reload|force-reload|status|configtest|bootstrap}  [ MySQL server options ]"
      exit 1
    ;;
esac

exit 0

启动相关 : 

默认以mysqld_safe启动数据库, 没有初始化集群的情况下会自动初始化(例如第一次启动mysql).

datadir建议指定, 否则就是默认的/var/lib/mysql, (见脚本)

case "$mode" in
  'start')
    # Start daemon

    # Safeguard (relative paths, core dumps..)
    cd $basedir

    echo $echo_n "Starting MySQL"
    if test -x $bindir/mysqld_safe
    then
      # Give extra arguments to mysqld with the my.cnf file. This script
      # may be overwritten at next upgrade.
      $bindir/mysqld_safe --datadir="$datadir" --pid-file="$mysqld_pid_file_path" $other_args >/dev/null 2>&1 &
      wait_for_ready; return_value=$?

      # Make lock for RedHat / SuSE
      if test -w "$lockdir"
      then
        touch "$lock_file_path"
      fi

      exit $return_value
    else
      log_failure_msg "Couldn't find MySQL server ($bindir/mysqld_safe)"
    fi
    ;;

启动后 : 

注意mysqld_safe还在, 同时调用mysqld启动了mysql server.

[root@mariadb usr]# ps -ewf|grep mysql
root         444       1  0 17:24 ?        00:00:00 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --pid-file=/var/lib/mysql/mariadb.pid
mysql        558     444  0 17:24 ?        00:00:00 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --user=mysql --log-error=/var/lib/mysql/mariadb.err --pid-file=/var/lib/mysql/mariadb.pid --wsrep_start_position=00000000-0000-0000-0000-000000000000:-1

[参考]

1.  https://mariadb.com/kb/en/mariadb/documentation/getting-started/starting-and-stopping-mariadb/mysqlserver/

2. /etc/init.d/mysql

3.  http://blog.163.com/digoal@126/blog/static/163877040201411533051172/