filesystem.in

在LINUX下实现HA的源代码

#!/bin/sh
#
# $Id: Filesystem.in,v 1.10 2003/07/03 02:14:14 alan Exp $
# 
# Filesystem
#      Description: Manages a Filesystem on a shared storage medium.
#  Original Author: Eric Z. Ayers ([e-mail])
# Original Release: 25 Oct 2000
#          Support: [e-mail]
#
# usage: ./Filesystem <device> <directory> <fstype> [<options>] {start|stop|status}
#
#<device>    : name of block device for the filesystem. e.g. /dev/sda1, /dev/md0
#		Or a -U or -L option for mount, or an NFS mount specification
#<directory> : the mount point for the filesystem
#<fstype>    : name of the filesystem type. e.g. ext2
#<options>   : options to be given to the mount command via -o
#
#
# An example usage in /etc/ha.d/haresources: 
#       node1  10.0.0.170 Filesystem::/dev/sda1::/data1::ext2
#  or
#       node1  10.0.0.170 Filesystem::-Ldata1::/data1::ext2
#  or
#       node1  10.0.0.170 Filesystem::server:/data1::/data1::nfs::ro
#
# This assumes you want to manage a filesystem on a shared (scsi) bus.
# Do not put this filesystem in /etc/fstab.  This script manages all of
# that for you.
#
# If you are interested in High Availability, you will probably also want
# some sort of external hardware RAID controller in front of the actual 
# disks.  I don't mean a RAID controller embedded in the host controller -
# it has to be a external controller.
#
# It can also be an internal RAID controller if the controller supports
# failover.  IBM's ServeRAID controller does this, and it automatically
# prohibits concurrent access too, so it's pretty cool in this application.
#
# There is a script for software RAID-1 included in this directory.  Right 
# now, I wouldn't recommend using software RAID (see notes in the Raid1 script)
#
# NOTE: There is no locking (such as a SCSI reservation) being done here.
#       I would if the SCSI driver could properly maintain the reservation,
#       which it cannot, even with the 'scsi reservation' patch submitted
#       earlier this year by James Bottomley.  The patch minimizes the
#       bus resets caused by a RESERVATION_CONFLICT return, and helps the 
#       reservation stay when 2 nodes contend for a reservation, 
#       but it does not attempt to recover the reservation in the 
#       case of a bus reset.  
#
#       What all this means is that if 2 nodes mount the same file system
#       read-write, the filesystem is going to become corrupted.
#
#	As a result, you should use this together with the stonith option
#	and redundant, independent communications paths.
#
#	If you don't do this, don't blame us when you scramble your disk.
# 
#	Note:  the ServeRAID controller does prohibit concurrent acess
#	In this case, you don't actually need STONITH, but redundant comm is
#	still an excellent idea.
#
unset LC_ALL; export LC_ALL
unset LANGUAGE; export LANGUAGE

prefix=@prefix@
exec_prefix=@exec_prefix@
#. @sysconfdir@/ha.d/shellfuncs
. /etc/ha.d/shellfuncs

# Utilities used by this script
MODPROBE=@MODPROBE@
FSCK=@FSCK@
FUSER=@FUSER@
MOUNT=@MOUNT@
UMOUNT=@UMOUNT@
BLOCKDEV=@BLOCKDEV@

check_util () {
    if [ ! -x "$1" ] ; then
	ha_log "ERROR: setup problem: Couldn't find utility $1"
	exit 1
    fi
}

usage() {

cat <<-EOT;
	usage: $0 <device> <directory> <fstype> [<options>] {start|stop|status}

	<device>    : name of block device for the filesystem. e.g. /dev/sda1, /dev/md0
	              OR -LFileSystemLabel OR -Uuuid or an NFS specification
	<directory> : the mount point for the filesystem
	<fstype>    : name of the filesystem type. e.g. ext2
	<options>   : options to be given as -o options to mount.

	$Id: Filesystem.in,v 1.10 2003/07/03 02:14:14 alan Exp $
	EOT
}

#
#	Make sure the kernel does the right thing with the FS buffers
#	This function should be called after unmounting and before mounting
#	It may not be necessary in 2.4 and later kernels, but it shouldn't hurt
#	anything either...
#
#	It's really a bug that you have to do this at all...
#
flushbufs() {
  if
    [ "$BLOCKDEV" != "" -a -x "$BLOCKDEV" ]
  then
    case $1 in
      -*|[^/]*:/*)	;;
      *)		$BLOCKDEV --flushbufs $1;;
    esac
  fi
}
# Check the arguments passed to this script
DEVICE=$1
MOUNTPOINT=$2
FSTYPE=$3

case $DEVICE in
  -*) # Oh... An option to mount instead...  Typically -U or -L
	;;
  [^/]*:/*)	# An NFS filesystem specification...
	;;
  *)	if [ ! -b "$DEVICE" ] ; then
	  ha_log "ERROR: Couldn't find device $DEVICE. Expected /dev/??? to exist"
	  usage
	  exit 1
	fi;;
esac

if [ ! -d "$MOUNTPOINT" ] ; then
	ha_log "ERROR: Couldn't find directory  $MOUNTPOINT to use as a mount point"
	usage
	exit 1	
fi
	

# Check to make sure the utilites are found
check_util $MODPROBE
check_util $FSCK
check_util $FUSER
check_util $MOUNT
check_util $UMOUNT

case $# in
  4)	operation=$4; options="";;
  5)	operation=$5; options="-o $4";;
  *)	usage; exit 1;;
esac
  

# Look for the 'start', 'stop' or status argument
case "$operation" in

#
# START: Start up the filesystem
#
start)

	# See if the device is already mounted.
	$MOUNT | cut -d' ' -f3 | grep -e "^$MOUNTPOINT$" >/dev/null
	if [ $? -ne 1 ] ; then
	    ha_log "ERROR: Filesystem $MOUNTPOINT is already mounted!"
	    exit 1;
	fi

	# Insert SCSI module
	$MODPROBE scsi_hostadapter >/dev/null 2>&1

	# Insert Filesystem module
	$MODPROBE $FSTYPE >/dev/null 2>&1
	grep -e "$FSTYPE"'$' /proc/filesystems >/dev/null
	if [ $? != 0  ] ; then
		ha_log "ERROR: Couldn't find filesystem $FSTYPE in /proc/filesystems"
		usage
		exit 1
	fi

	# Check the filesystem & auto repair.  
	# NOTE: Some filesystem types don't need this step...  Please modify
	#       accordingly

	if
	  case $FSTYPE in
	    ext3|reiserfs|xfs|jfs|vfat|fat|nfs)	false;;
	    *)				true;;
	  esac
        then
	  ha_log "info: Starting filesystem check on $DEVICE"
	  $FSCK -t $FSTYPE -a $DEVICE
	
	  # NOTE: if any errors at all are detected, it returns non-zero
	  # if the error is >4 then there is a big problem
	  if
	    [ $? -ge 4 ]
	  then
	    ha_log "ERROR: Couldn't sucessfully fsck filesystem for $DEVICE"
	    exit 1	
	  fi	
	fi

	flushbufs $DEVICE
	# Mount the filesystem.
	if
	  $MOUNT -t $FSTYPE $options $DEVICE $MOUNTPOINT
        then
	  : Mount worked!
        else
	  ha_log "ERROR: Couldn't mount filesystem $DEVICE on $MOUNTPOINT"
	  exit 1
	fi

# end of start)
;;

#
# STOP: Unmount the filesystem
#
stop)

	# See if the device is currently mounted
	if
	  $MOUNT | grep -e " on $MOUNTPOINT " >/dev/null
	then
		# Kill all processes open on filesystem
		$FUSER -mk $MOUNTPOINT

		# Get the current real device name...
		# (specified devname could be -L or -U...)

		DEV=`$MOUNT | grep "on $MOUNTPOINT " | cut -d' ' -f1`
		# Unmount the filesystem
		$UMOUNT $MOUNTPOINT
		if [ $? -ne 0 ] ; then
			ha_log "ERROR: Couldn't unmount $MOUNTPOINT"
			exit 1
		fi
		flushbufs $DEV
	else
		ha_log "WARNING: Filesystem $MOUNTPOINT not mounted?"
	fi

# end of stop)
;;

#
# STATUS: is the filesystem mounted or not?
#
status)

	$MOUNT | grep -e "on $MOUNTPOINT " >/dev/null
	if [ $? = 0 ] ; then
		echo "$MOUNTPOINT is mounted (running)"
	else
		echo "$MOUNTPOINT is unmounted (stopped)"
	fi
# end of status)
;;


*)
    echo "This script should be run with a fourth argument of 'start', 'stop', or 'status'"
    usage
    exit 1
;;

esac

# If you got to this point, chances are everything is O.K.
exit 0;