Simple EC2 Snapshot Management

#Backup all instances
for a in $(ec2-describe-volumes |grep -Ev "ATTACHMENT" |cut -f2);do ec2-create-snapshot $a; done;

is_older()
{
  DATE=$(date -d "$1" +%Y-%m-%d)
  TODAY=$(date -d "$(date +%Y-%m-%d) $2 $3 $4 $5" +%s)
  COMPARE=$(date -d "$DATE" +%s)
  test $(($TODAY - $COMPARE)) -le 0 && return 1 || return 0
}

#Purge old records
for snapid in $(ec2-describe-snapshots |grep -Ev "ATTACHMENT"| cut -f2 );do

  snapdate=$(ec2-describe-snapshots $snapid | cut -f5 | cut -d "T" -f1)
  if is_older $snapdate -7 days ;then
    ec2-delete-snapshot $snapid
  fi
done;