#!/bin/bash
#
# Create LVM Snapshots
#
#
#---------------------------------------------------------------------------------------------------------------
CURRENT_SNAPNAME="snap-"$(date "+%Y%m%d%H%M%S")
VOLUME2SNAPSHOT="/dev/vol_backup/lvm0"
LVMSNAPSHOTCMD="/usr/sbin/lvcreate -L 2G -s -n $CURRENT_SNAPNAME $VOLUME2SNAPSHOT"
LINE="---------------------------------------------------------------------------------------------------------------------"

echo $LINE
df -h /mnt/data
echo $LINE
$LVMSNAPSHOTCMD 2> /dev/null
#---------------------------------------------------------------------------------------------------------------
SNAPSHOT_RETENTION=15
CURRENT_SNAPSHOT_COUNT=$(lvdisplay | grep "^  LV Name                /dev/vol_backup/snap" | sort | awk '{ print $3 }' | wc -l)

OVERFLOW=$(echo $CURRENT_SNAPSHOT_COUNT - $SNAPSHOT_RETENTION | bc)
if [ $OVERFLOW -gt 0 ];
then
        echo $LINE
	for files in  $(lvdisplay | grep "^  LV Name                /dev/vol_backup/snap" | sort | awk '{ print $3 }' | head -n$OVERFLOW);
	do
		 /usr/sbin/lvremove -f $files 2> /dev/null
	done
fi
#---------------------------------------------------------------------------------------------------------------
echo $LINE
/usr/sbin/vgdisplay vol_backup
echo $LINE
/usr/sbin/lvdisplay $VOLUME2SNAPSHOT