ebs snapshot

ebs snapshot

#!/bin/bash

# ebs-snapshot.sh. Performs and validates EBS snapshots.

# snapshot date format 20111118-2305
snapshot_date=`date +s%Y%m%d-%H%M`

# Set name of script 
progname=${0##*/} ## Get the name of the script without its path

# Print script usage information. -b can be a single EBS volume ID or a comma separated list of volume IDs
print_usage() { printf "USAGE: ./%s -b Volume1,volume2" "$progname."}

# Exit with error if there are no command-line arguments given
if [ -z "$*" ]; then print_usage ; exit 1; fi

# Print error message and exit with error code. 
# Usage: die [errno [message]]
die() {
  error=${1:-1} ## exits with 1 if error number not given
  shift
  [ -n "$*" ] &&
  printf "%s%s: %s\n" "$scriptname" ${version:+" ($version)"} "$*" >&2
  exit "$error"
}

# Main snapshot function, takes 1 argument, the volume ID, and outputs the corresponding snapshot ID into /tmp/last_snapshot 
ebs_snapshot() {
  # ${variable%\\n} is the shell equivalent of CHOMP.
  ec2-create-snapshot -d backup-"$1"-"${snapshot_date%\\n}" |awk '{print $2}' > /tmp/"$1"-last || die "Unable to take snapshot of volume $1"
}

#  Check the snapshot status. 
snapshot_status() {
  ec2-describe-snapshots -C <%= aws-cert-file %> -K <%= aws-key-file %> $1
}

# Define the required and optional command-line options for processing by getopts
optstring=b:

# Process command-line arguments
while getopts $optstring opt
do
  case $opt in
    b) ebs_volumes=$OPTARG ;;
    *) print_usage ; exit 1
  esac
done

# Main program loop. Performs a snapshot on each volume passed to it. 
for i in `echo $ebs_volumes |sed 's/\,/ /g'` do
  ebs_snapshot $i
  completed=false
  until [ $completed = "true" ]; do
    snapshot_status `cat /tmp/"$i"-last` |grep completed
    if [ $? = 0 ];
      completed="true"
    elif [ $? = 1 ];
      completed = "false"
    fi
  done      
done