Script to find AWS EC2 Snapshots created for AMIs that no longer exist

aws-ec2-dead-snapshots.sh

#!/bin/bash

# Locate dead AWS EC2 Snapshots

# This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.


function show_help() {
  echo "$0: -o <owner id> -r <aws-region> -p <aws-cli-profile> -v"
}

OPTIND=1 # Reset in case getopts has been used previously in the shell.

# Initialize our own variables:
OWNER=""
VERBOSE=0
REGION="us-east-1"
PROFILE="default"

while getopts "h?vo:r:p:" opt; do
    case "$opt" in
    h|\?)
        show_help
        exit 0
        ;;
    v)  VERBOSE=1
        ;;
    o)  OWNER="--owner-ids ${OPTARG}"
        ;;
    r)  REGION=$OPTARG
        ;;
    p)  PROFILE=$OPTARG
        ;;
    esac
done

shift $((OPTIND-1))

[ "${1:-}" = "--" ] && shift

SNAPSHOTS="/tmp/snapshots.txt"

aws --profile ${PROFILE} --region ${REGION} ec2 describe-snapshots ${OWNER} --output text --query 'Snapshots[*].SnapshotId' > ${SNAPSHOTS}

if [[ ${VERBOSE} == 1 ]]
then
  SNAPCOUNT=$(grep -o 'snap' ${SNAPSHOTS} | wc -l)
  echo "Scanning ${SNAPCOUNT} snapshots"
fi

for snap in $(cat ${SNAPSHOTS})
do
   if [[ ${VERBOSE} == 1 ]]
   then
     echo "Checking: $snap"
   fi

   DESC=$(aws --profile ${PROFILE} --region ${REGION} ec2 describe-snapshots --snapshot-ids ${snap} --output text --query 'Snapshots[*].Description')

   if [[ "${DESC}" =~ .*"Created by CreateImage".* ]]
   then
     AMI=$(echo "$DESC" | grep -oP "(ami-[0-9a-z]*)")
     aws --profile ${PROFILE} --region ${REGION} ec2 describe-images --image-ids ${AMI} 2> /dev/null > /dev/null || echo "Dead: ${snap}"
   fi
done

rm -f ${SNAPSHOTS}

exit 0