#!/bin/sh
#
#
# License:      GNU General Public License (GPL)
# Support:      linux-ha@lists.linux-ha.org
# 
# Raid1
#      Description: Manages a software Raid1 device on a shared storage medium.
#  Original Author: Eric Z. Ayers (eric.ayers@compgen.com)
# Original Release: 25 Oct 2000
#     RAID patches: http://people.redhat.com/mingo/raid-patches/
# Word to the Wise: http://lwn.net/2000/0810/a/raid-faq.php3
#  Sympathetic Ear: mailto:linux-raid@vger.kernel.org
#
# usage: $0 {start|stop|status|monitor|validate-all|usage|meta-data}
#
#	  OCF parameters are as below:
#		OCF_RESKEY_raidconf
#                  (name of MD configuration file. e.g. /etc/raidtab or /etc/mdadm.conf)
#		OCF_RESKEY_raiddev
#                  (of the form /dev/md* the block device to use)   
#
# in /etc/ha.d/haresources, use a line such as:
# nodea  10.0.0.170 Raid1::/etc/raidtab.md0::/dev/md0 Filesystem::/dev/md0::/data1::ext2
# (for systems with raidtools)
#	or
# nodea  10.0.0.170 Raid1::/etc/mdadm.conf::/dev/md0 Filesystem::/dev/md0::/data1::ext2
# (for systems with mdadm)
#
# The "start" arg starts up the raid device
# The "stop" arg stops it.  NOTE: all filesystems must be unmounted
#  and no processes should be accessing the device.
# The "status" arg just prints out whether the device is running or not
#
# 
# DISCLAIMER: Use at your own risk!
#
#  Besides all of the usual legalese that accompanies free software, 
#  I will warn you that I do not yet use this kind of setup (software RAID 
#  over shared storage) in production, and I have reservations about doing so.
#
#  The linux md driver/scsi drivers under Raid 0.90 and kernel version 2.2 
#  do not behave well when a drive is in the process of going bad.  
#  The kernel slows down, but doesn't completely crash.  This is about the 
#  worst possible thing that could happen in an un-attended HA type 
#  environment.  (Once the system is rebooted, the sofware raid stuff works 
#  like a champ.)  
#  My other reservation has to do with the interation of RAID recovery with 
#  journaling filesystems and other parts of the kernel.  Subscribe to 
#  linux-raid@vger.kernel.org  for other opinions and possible solutions.
#
#  -EZA 25 Oct 2000 
# 
# SETUP:
#
# You might need to pass the command line parameter: raid=noautodetect 
# in an HA environment so that the kernel doesn't automatically start
# up your raid partitions when you boot the node.  This means that it isn't
# going to work to use RAID for the system disks and the shared disks.
#
# 0) partition the disks to use for RAID.  Use normal Linux partition 
#    types, not the RAID autodetect type for your partitions.
# 1) Create /etc/raidtab.md?  on both systems (see example file below)
#    or for systems with mdadm tools create /etc/mdadm.conf (see example below)
# 2) Initialize your raid partition with 
#	/sbin/mkraid --configfile /etc/raidtab.md? /dev/md?
#    or create mirror raid with the following command  
#	mdadm --create /dev/md? -l 1 -n 2 /dev/sdb? /dev/sdb?
# 3) Format your filesystem
#	mke2fs /dev/md0  # for ext2fs... a journaling filesystem would be nice
# 3) Create the mount point on both systems.
#    DO NOT add your raid filesystem to /etc/fstab
# 4) copy this script (to /etc/rc.d/init.d if you wish) and edit it to
#    reflect your desired settings.
# 5) Modify the heartbeat 'haresources' (for non-crm heartbeat) or 'cib.xml' (for crm heartbeat) setup file
# 6) unmount the filesystem and stop the raid device with 'raidstop' or 'mdadm -S'
# 7) fire up heartbeat!
#
# 
# EXAMPLE config file /etc/raidtab.md0
# This file must exist on both machines!
#
#  raiddev		    /dev/md0
#  raid-level		    1
#  nr-raid-disks	    2
#  chunk-size		    64k
#  persistent-superblock    1
#  #nr-spare-disks	    0
#    device	    /dev/sda1
#    raid-disk     0
#    device	    /dev/sdb1
#    raid-disk     1
#
# EXAMPLE config file /etc/mdadm.conf (for more info:man mdadm.conf)
#
#  DEVICE /dev/sdb1 /dev/sdb2 
#  ARRAY /dev/md0 level=raid1 UUID=4a865b55:ba27ef8d:29cd5701:6fb42799
#######################################################################
# Initialization:

. ${OCF_ROOT}/resource.d/heartbeat/.ocf-shellfuncs

#######################################################################

usage() {
	cat <<-EOT
	usage: $0 {start|stop|status|monitor|validate-all|usage|meta-data}
	EOT
}

meta_data() {
	cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="Raid1">
<version>1.0</version>

<longdesc lang="en">
Resource script for RAID1. It manages a software Raid1 device on a shared 
storage medium. 
</longdesc>
<shortdesc lang="en">RAID1 resource agent</shortdesc>

<parameters>
<parameter name="raidconf" unique="0" required="1">
<longdesc lang="en">
The RAID configuration file. e.g. /etc/raidtab or /etc/mdadm.conf.
</longdesc>
<shortdesc lang="en">RAID config file</shortdesc>
<content type="string" default="" />
</parameter>

<parameter name="raiddev" unique="0" required="1">
<longdesc lang="en">
The block device to use.
</longdesc>
<shortdesc lang="en">block device</shortdesc>
<content type="string" default="" />
</parameter>

<parameter name="homehost" unique="0" required="0">
<longdesc lang="en">
The value for the homehost directive; this is an mdadm feature to
protect RAIDs against being activated by accident. It is recommended to
create RAIDs managed by the cluster with "homehost" set to a special
value, so they are not accidentially auto-assembled by nodes not
supposed to own them.
</longdesc>
<shortdesc lang="en">Homehost for mdadm</shortdesc>
<content type="string" default="" />
</parameter>
</parameters>

<actions>
<action name="start" timeout="10" />
<action name="stop" timeout="10" />
<action name="status" depth="0" timeout="10" interval="10" start-delay="10" />
<action name="monitor" depth="0" timeout="10" interval="10" start-delay="10" />
<action name="validate-all" timeout="5" />
<action name="meta-data" timeout="5" />
</actions>
</resource-agent>
END
}

#
# START: Start up the RAID device
#
raid1_start() {
	# See if the md device is already mounted.
	$MOUNT | grep -e "^$MDDEV\>" >/dev/null
	if [ $? -ne 1 ] ; then
	    ocf_log err "Device $MDDEV is already mounted!"
	    return $OCF_ERR_GENERIC
	fi
	
	if [ "running" = `raid1_status` ]; then
	# We are already online, do not bother
	    return $OCF_SUCCESS
	fi

	# Insert SCSI module
	$MODPROBE scsi_hostadapter
	if [ $? -ne 0 ] ; then
	    ocf_log warn "Couldn't insert SCSI module."
	fi

	# Insert raid personality module
	$MODPROBE raid1
	if [ $? -ne 0 ] ; then
	# It is not fatal, chance is that we have raid1 builtin...
	    ocf_log warn "Couldn't insert RAID1 module"
	fi
	grep -q "^Personalities.*\[raid1\]" /proc/mdstat 2>/dev/null
	if [ $? -ne 0 ] ; then
	    ocf_log err "We don't have RAID1 support! Exiting"
	    return $OCF_ERR_GENERIC
	fi

	if [ $HAVE_RAIDTOOLS = "true" ]; then
	    # Run raidstart to start up the RAID array
	    $RAIDSTART --configfile $RAIDCONF $MDDEV
	else
	    # Run mdadm
	    $MDADM --assemble $MDDEV --config=$RAIDCONF $MDADM_HOMEHOST
	fi

	if [ "running" = `raid1_status` ]; then
	    return $OCF_SUCCESS
	else
	    ocf_log err "Couldn't start RAID for $MDDEV"
	    return $OCF_ERR_GENERIC
	fi
}

#
# STOP: stop the RAID device
#
raid1_stop() {
	# See if the MD device is online
	if [ "stopped" = `raid1_status` ]; then
		return $OCF_SUCCESS
	fi

	# See if the MD device is mounted
	$MOUNT | grep -e "^$MDDEV\>" >/dev/null
	if [ $? -ne 1 ] ; then
		# Kill all processes open on filesystem
		$FUSER -m -k $MDDEV

		# the return from fuser doesn't tell us much
		#if [ $? -ne 0 ] ; then
		#	ocf_log "err" "Couldn't kill processes on $MOUNTPOINT"
		#	return 1;
		#fi

		# Unmount the filesystem
		$UMOUNT $MDDEV

		$MOUNT | grep -e "^$MDDEV\>" >/dev/null
		if [ $? -ne 1 ] ; then
		    ocf_log err "filesystem for $MDDEV still mounted"
		    return $OCF_ERR_GENERIC
		fi
	fi

	# Turn off raid
	if [ $HAVE_RAIDTOOLS = "true" ]; then
		$RAIDSTOP --configfile $RAIDCONF $MDDEV
	else
		$MDADM --stop $MDDEV --config=$RAIDCONF $MDADM_HOMEHOST
	fi

	if [ $? -ne 0 ] ; then
		ocf_log err "Couldn't stop RAID for $MDDEV"
		return $OCF_ERR_GENERIC
	fi

	return $OCF_SUCCESS
}

#
# STATUS: is the raid device online or offline?
#
raid1_status() { 

	# See if the MD device is online
	grep -e "^$MD[ \t:]" /proc/mdstat >/dev/null
	if [ $? -ne 0 ] ; then
	    echo "stopped"
	    return $OCF_NOT_RUNNING
	else
	    echo "running"
	    return $OCF_SUCCESS
	fi

}    

raid1_validate_all() {
    # Utilities used by this script
    check_binary $MODPROBE
    check_binary $FSCK
    check_binary $FUSER
    check_binary $MOUNT
    check_binary $UMOUNT

	if [ $HAVE_RAIDTOOLS = "true" ]; then

	    # $MDDEV should be an md device
	    lsraid -a $MDDEV 2>&1 | grep -q -i "is not an md device"
	    if [ $? -eq 0 ]; then
		ocf_log err "$MDDEV is not an md device!"
		exit $OCF_ERR_ARGS
	    fi
		
	    COMMENT="\(#.*\)"
	    grep -q "^[[:space:]]*raiddev[[:space:]]\+$MDDEV[[:space:]]*$COMMENT\?$" $RAIDCONF 2>/dev/null
	    if [ $? -ne 0 ]; then
		ocf_log err "Raid device $MDDEV does not appear in $RAIDCONF"
		exit $OCF_ERR_GENERIC
	    fi
	else
	    error=`$MDADM --query $MDDEV $MDADM_HOMEHOST 2>&1`
	    if [ $? -ne 0 ]; then
		ocf_log err "$error"
		exit $OCF_ERR_GENERIC
	    fi
	    echo $error | grep -q -i "^$MDDEV[ \t:].*is not an md array"
	    if [ $? -eq 0 ]; then
		ocf_log err "$MDDEV is not an md array!"
		exit $OCF_ERR_ARGS
	    fi
	fi

	return $OCF_SUCCESS
}
	

if
  ( [ $# -ne 1 ] )
then
  usage
  exit $OCF_ERR_ARGS
fi

case "$1" in
  meta-data)
	meta_data
	exit $OCF_SUCCESS
	;;
  usage) 
	usage
	exit $OCF_SUCCESS
	;;
  *)
	;;
esac

#
# Check the necessary enviroment virable's setting 
# 

RAIDCONF=$OCF_RESKEY_raidconf
MDDEV=$OCF_RESKEY_raiddev

if [ -z "$RAIDCONF" ] ; then
	ocf_log err "Please set OCF_RESKEY_raidconf!"
	exit $OCF_ERR_ARGS
fi

if [ ! -r "$RAIDCONF" ] ; then
	ocf_log err "Configuration file [$RAIDCONF] does not exist, or can not be opend!"
	exit $OCF_ERR_ARGS
fi

if [ -z "$MDDEV" ] ; then
	ocf_log err "Please set OCF_RESKEY_raiddev to the Raid device you want to control!"
	exit $OCF_ERR_ARGS
fi

if [ ! -b "$MDDEV" ] ; then
	ocf_log err "$MDDEV is not a block device!"
	exit $OCF_ERR_ARGS
fi

# strip off the /dev/ prefix to get the name of the MD device
MD=`echo $MDDEV | sed -e 's/\/dev\///'`


HAVE_RAIDTOOLS=false
if 
    have_binary $RAIDSTART
then
  check_binary $RAIDSTOP
  HAVE_RAIDTOOLS=true
else
  check_binary $MDADM
  if [ -n "$OCF_RESKEY_homehost" ]; then
  	MDADM_HOMEHOST="--homehost=${OCF_RESKEY_homehost}"
  else
  	MDADM_HOMEHOST=""
  fi
fi

# At this stage,
# [ $HAVE_RAIDTOOLS = false ] <=> we have $MDADM,
# otherwise we have raidtools (raidstart and raidstop)

# Look for how we are called 
case "$1" in
  start)
	raid1_start
	;;
  stop)
	raid1_stop
	;;
  status|monitor) 
	raid1_status
	;;
  validate-all)
	raid1_validate_all
	;;
  *)
	usage
	exit $OCF_ERR_UNIMPLEMENTED 
	;;
esac

exit $?
