#!/bin/sh
#
# $Id: db2.in,v 1.6 2002/05/16 14:56:28 alan Exp $
# 
# db2
#
# Description:	Manages a DB2 Universal Database as a High-Availability
#		resource
#
#
# Author:	Alan Robertson
#		Support: linux-ha-dev@lists.tummy.com
# License:	GNU Lesser General Public License (LGPL)
# Copyright:	(C) 2002 International Business Machines, Inc.
#
#		This code inspired by the FailSafe db2 resource script
#		written by Joachim Gleissner <jg@suse.de>
#
# An example usage in /etc/ha.d/haresources: 
#       node1  10.0.0.170 db2::db2inst1
#
# See usage() function below for more details...
#
unset LC_ALL; export LC_ALL
unset LANGUAGE; export LANGUAGE

usage() {
  methods=`db2_methods | grep -v methods`
  methods=`echo $methods | tr ' ' '|'`
  cat <<-! >&1
	usage: $0 db2-database-owner-id ($methods)
	usage: $0 methods

	$0 manages a DB2 Universal Database instance as an HA resource.

	The 'start' operation starts the database.
	The 'stop' operation stops the database.
	The 'status' operation reports whether the database is running
	The 'monitor' operation reports whether the database seems to be working
	The 'methods' operation reports on the methods $0 supports

	$Id: db2.in,v 1.6 2002/05/16 14:56:28 alan Exp $
	!
  exit 1

}


prefix=/usr
exec_prefix=/usr
#. /etc/ha.d/shellfuncs
. /etc/ha.d/shellfuncs
SH=/bin/bash


#
# methods: What methods/operations do we support?
#
db2_methods() {
  cat <<-!
	start
	stop
	status
	monitor
	methods
	!
}


#	Gather up information about our db2 instance

db2info() {
	instance=$1
	db2admin=$instance
	db2home=`bash -c "echo ~$db2admin"`
	db2sql=$db2home/sqllib
	db2profile=$db2sql/db2profile
	db2adm=$db2sql/adm
	db2ctrl=$db2sql/ctrl
	db2bin=$db2sql/bin
	db2db2=$db2bin/db2

	#	Let's make sure a few important things are there...
	if
	  [ -d "$db2sql" -a  -d "$db2bin" -a -f "$db2profile" -a \
		-x "$db2profile" -a -x "$db2db2" ]
	then
	  db2instance=`runasdb2 'echo $DB2INSTANCE'`
	  test ! -z "$db2instance"
        else
	  false
	fi
	rc=$?
	if
	  [ $rc -ne 0 ]
	then
	  ha_log "ERROR: DB2 instance [$instance] not available"
	fi
	return $rc
}

#
#	Run the given command in the db2 admin environment...
#
runasdb2() {
	if
	  [ $US = $db2admin ]
	then
	  $SH -c ". $db2profile; $*"
	else
	  su $db2admin -c ". $db2profile; $*"
	fi
}

#
#	Run a command as the DB2 admin, and log the output
#
logasdb2() {
	output=`runasdb2 $*`
	rc=$?
	if
	  [ $rc -eq 0 ]
	then
	  ha_log "info: $output"
	else
	  ha_log "ERROR: $output"
	fi
	return $rc
}


#
# db2_start: Start the given db2 instance
#
db2_start() {
  if
    output=`runasdb2 $db2adm/db2start`
  then
    : Hurray! DB2 started OK
    ha_log "info: DB2 UDB instance $1 started: $output"
  else
    case $output in
      SQL1026N*|*"is already active"*)
    		ha_log "info: DB2 UDB instance $1 already running: $output";;

      *)	ha_log "ERROR: $output"; return 1;;
    esac
  fi
  if
    db2_status "$1"
  then
    if
      runasdb2 $db2bin/db2jstrt 
    then
      for DB in `db2_dblist`
      do
        runasdb2 $db2db2 activate database $DB
      done
    fi
    return $?
  else
    echo "ERROR: DB2 UDB instance $1 not active!"
    return 1
  fi
}

#
# db2_stop: Stop the given db2 database instance
#
db2_stop() {
  # We ignore the instance, the info we need is already in $vars
  rc=0
  if
    output=`runasdb2 $db2adm/db2stop force`
  then
    : DB2 stopped OK
    ha_log "info: DB2 UDB instance $1 stopped: $output"
  else
    case $output in

      SQL1032N*|*"No start database manager command"*)
		ha_log "info: $output";;

      *)	ha_log "ERROR: DB2 UDB instance $1 stop failed: $output"
		rc=1;;
    esac
  fi
  logasdb2 $db2db2 terminate
  logasdb2 $db2bin/db2_kill
  pids=`our_db2_ps | grep db2jd | cut -d' ' -f1`
  for j in $pids
  do
    runasdb2 kill -9 $j
  done
  return $rc
}


#
# db2_status: is the given db2 instance running?
#
db2_status() {
  # We ignore the instance, the info we need is already in $vars
  pscount=`runasdb2 $db2bin/db2_local_ps | grep ' db2[^ ]*$' | wc -l`
  test $pscount -ge 5
}

our_db2_ps() {
  ps -u $db2admin | grep db2
}


db2_dblist() {
  runasdb2 $db2db2 list database directory	\
  |	grep -i 'Database name.*=' | sed 's%.*= *%%'
}


#
# db2_monitor: Can the given db2 instance do anything useful?
#
db2_monitor() {
  # We ignore the instance, the info we need is already in $vars
  for DB in `db2_dblist`
  do

  CMD="	if $db2db2 connect to $DB;
	then 
	  $db2db2 select \* from sysibm.sysversions ; rc=\$?;
	  $db2db2 disconnect $DB;
	else
          rc=\$?;
	fi;
	exit \$rc"

    : Running this command: $CMD
    if
      output=`runasdb2 $CMD`
    then
      : Command succeeded!
    else
      ha_log "ERROR: DB2 UDB instance $1 DB $DB is not working"
      ha_log "ERROR: DB2 UDB message: $output"
      return 1
    fi
  done
  : ha_log "info: All DBs in DB2 UDB instance $1 appear to be working"
}

#
#	'main' starts here...
#

if
  [ $# -le 1 ]
then
  if
    [ "methods" = "$1" ]
  then
    db2_methods
    exit $?
  else
    usage
    exit $?
  fi
fi

US=`id -u -n`
US=`echo $US`
if
  [ $US != root -a $US != $1 ]
then
  ha_log "ERROR: $0 must be run as root or $1"
  exit 1
fi

#
#	Grab common db2 information...
#
if
  db2info $1 
then
  : DB2 info is OK!
else
  rc=$?
  exit $rc
fi


# What kind of method was invoked?
case "$2" in

  start)	db2_start $instance
		exit $?;;

  stop)		db2_stop $instance
		exit $?;;

  status)	if
		  db2_status $instance
		then
		  echo DB2 UDB instance $instance is running
		  exit 0
		else
		  echo DB2 UDB instance $instance is stopped
		  exit 1
		fi
		exit $?;;

  monitor)	db2_monitor $instance
		exit $?;;

  methods)	db2_methods
		exit $?;;
esac

usage