MongoDB Run As a Service – Linux

MongoDB Run As a Service 

• If you are installing mongodb with the default installer like yum or with rpm, by default the init.d scripts will be generated for mongo and the service commands also will be in place 

• But if you are installing mongodb with tarball or binary installer, there will not be any init scripts and service commands will not work as well.

Example:

Here am gonna show you how to run mongodb as a service with tarball or binary installation.

Rules: 

• There should be mongod script placed in /etc/init.d/mongod

• All files in db_path, logpath, binary path, config file path should be in the ownership of mongod (user and group)

Paths:

The below mentioned paths may change based on your installation, but mongod script path should the same as given below.

Mongod script path  - /etc/init.d/mongod

Binary path - /data/mongodb-3.2.18/bin/mongod

Config file path - /data/config/mongod.conf

You don want to worry about the below given script, as we gonna change only to path variable in the script.

Sample Config File:

net:
  port: 27019
processManagement:
  pidFilePath: /var/run/mongodb/mongod.pid
  fork: true
sharding:
  clusterRole: shardsvr
replication:
  replSetName: rs_0
storage:
  dbPath: /data/usr/mongod_data
systemLog:
  destination: file
  logAppend: true
  logRotate: rename

  path: /data/usr/logs/mongod.log

mongod script:

#!/bin/bash

# mongod - Startup script for mongod

# chkconfig: 35 85 15

# description: Mongo is a scalable, document-oriented database.

# processname: mongod

# config: /etc/mongod.conf

. /etc/rc.d/init.d/functions

# NOTE: if you change any OPTIONS here, you get what you pay for:

# this script assumes all options are in the config file.

CONFIGFILE="/data/config/mongod.conf"

OPTIONS=" -f $CONFIGFILE"

mongod=${MONGOD-/data/mongodb-3.2.18/bin/mongod}

MONGO_USER=mongod

MONGO_GROUP=mongod

# All variables set before this point can be overridden by users, by

# setting them directly in the SYSCONFIG file. Use this to explicitly

# override these values, at your own risk.

SYSCONFIG="/etc/sysconfig/mongod"

if [ -f "$SYSCONFIG" ]; then

    . "$SYSCONFIG"

fi

# Handle NUMA access to CPUs (SERVER-3574)

# This verifies the existence of numactl as well as testing that the command works

NUMACTL_ARGS="--interleave=all"

if which numactl >/dev/null 2>/dev/null && numactl $NUMACTL_ARGS ls / >/dev/null 2>/dev/null

then

    NUMACTL="numactl $NUMACTL_ARGS"

else

    NUMACTL=""

fi

# things from mongod.conf get there by mongod reading it

PIDFILEPATH=`awk -F'[:=]' -v IGNORECASE=1 '/^[[:blank:]]*(processManagement\.)?pidfilepath[[:blank:]]*[:=][[:blank:]]*/{print $2}' "$CONFIGFILE" | tr -d "[:blank:]\"'" | awk -F'#' '{print $1}'`

PIDDIR=`dirname $PIDFILEPATH`

start()

{

  # Make sure the default pidfile directory exists

  if [ ! -d $PIDDIR ]; then

    install -d -m 0755 -o $MONGO_USER -g $MONGO_GROUP $PIDDIR

  fi

  # Make sure the pidfile does not exist

  if [ -f $PIDFILEPATH ]; then

      echo "Error starting mongod. $PIDFILEPATH exists."

      RETVAL=1

      return

  fi

  # Recommended ulimit values for mongod or mongos

  # See http://docs.mongodb.org/manual/reference/ulimit/#recommended-settings

  #

  ulimit -f unlimited

  ulimit -t unlimited

  ulimit -v unlimited

  ulimit -n 64000

  ulimit -m unlimited

  ulimit -u 64000

  echo -n $"Starting mongod: "

  daemon --user "$MONGO_USER" --check $mongod "$NUMACTL $mongod $OPTIONS >/dev/null 2>&1"

  RETVAL=$?

  echo

  [ $RETVAL -eq 0 ] && touch /var/lock/subsys/mongod

}

stop()

{

  echo -n $"Stopping mongod: "

  mongo_killproc "$PIDFILEPATH" $mongod

  RETVAL=$?

  echo

  [ $RETVAL -eq 0 ] && rm -f /var/lock/subsys/mongod

}

restart () {

        stop

        start

}

# Send TERM signal to process and wait up to 300 seconds for process to go away.

# If process is still alive after 300 seconds, send KILL signal.

# Built-in killproc() (found in /etc/init.d/functions) is on certain versions of Linux

# where it sleeps for the full $delay seconds if process does not respond fast enough to

# the initial TERM signal.

mongo_killproc()

{

  local pid_file=$1

  local procname=$2

  local -i delay=300

  local -i duration=10

  local pid=`pidofproc -p "${pid_file}" ${procname}`

  kill -TERM $pid >/dev/null 2>&1

  usleep 100000

  local -i x=0

  while [ $x -le $delay ] && checkpid $pid; do

    sleep $duration

    x=$(( $x + $duration))

  done

  kill -KILL $pid >/dev/null 2>&1

  usleep 100000

  checkpid $pid # returns 0 only if the process exists

  local RC=$?

  [ "$RC" -eq 0 ] && failure "${procname} shutdown" || rm -f "${pid_file}"; success "${procname} shutdown"

  RC=$((! $RC)) # invert return code so we return 0 when process is dead.

  return $RC

}

RETVAL=0

case "$1" in

  start)

    start

    ;;

  stop)

    stop

    ;;

  restart|reload|force-reload)

    restart

    ;;

  condrestart)

    [ -f /var/lock/subsys/mongod ] && restart || :

    ;;

  status)

    status $mongod

    RETVAL=$?

    ;;

  *)

    echo "Usage: $0 {start|stop|status|restart|reload|force-reload|condrestart}"

    RETVAL=1

esac

exit $RETVAL

Path Variable to be changed for your installation:

The above mentioned are the two variables to be take care in the entire script

Just change the config file path and the binary path, the given script will work for most of the binary installations.

After doing this the service commands will work for you, 

• Start – sudo service mongod start
• Stop – sudo service mongod stop
• Restart - sudo service mongod restart

Start:

# sudo service mongod start

When we checked the process, it’s not running but when we trigged the command – the mongo process automatically started.

Stop:

# sudo service mongod stop

Here when we checked the process, its already running but when we triggered the command it stopped.

Restart:

 # sudo service mongod restart

As same as start and stop, its restarted.

Done…