232 lines
10 KiB
Bash
Executable File
232 lines
10 KiB
Bash
Executable File
#!/bin/bash -
|
|
# Author: Colin Johnson / colin@cloudavail.com
|
|
# Date: 2013-01-27
|
|
# Version 0.1
|
|
# License Type: GNU GENERAL PUBLIC LICENSE, Version 3
|
|
#
|
|
#confirms that executables required for succesful script execution are available
|
|
prerequisite_check()
|
|
{
|
|
for prerequisite in basename ec2-create-snapshot ec2-create-tags ec2-describe-snapshots ec2-delete-snapshot date
|
|
do
|
|
#use of "hash" chosen as it is a shell builtin and will add programs to hash table, possibly speeding execution. Use of type also considered - open to suggestions.
|
|
hash $prerequisite &> /dev/null
|
|
if [[ $? == 1 ]] #has exits with exit status of 70, executable was not found
|
|
then echo "In order to use `basename $0`, the executable \"$prerequisite\" must be installed." 1>&2 ; exit 70
|
|
fi
|
|
done
|
|
}
|
|
|
|
#get_EBS_List gets a list of available EBS instances depending upon the selection_method of EBS selection that is provided by user input
|
|
get_EBS_List()
|
|
{
|
|
case $selection_method in
|
|
volumeid)
|
|
if [[ -z $volumeid ]]
|
|
then echo "The selection method \"volumeid\" (which is $app_name's default selection_method of operation or requested by using the -s volumeid parameter) requires a volumeid (-v volumeid) for operation. Correct usage is as follows: \"-v vol-6d6a0527\",\"-s volumeid -v vol-6d6a0527\" or \"-v \"vol-6d6a0527 vol-636a0112\"\" if multiple volumes are to be selected." 1>&2 ; exit 64
|
|
fi
|
|
ebs_selection_string="$volumeid"
|
|
;;
|
|
tag)
|
|
if [[ -z $tag ]]
|
|
then echo "The selected selection_method \"tag\" (-s tag) requires a valid tag (-t key=value) for operation. Correct usage is as follows: \"-s tag -t backup=true\" or \"-s tag -t Name=my_tag.\"" 1>&2 ; exit 64
|
|
fi
|
|
ebs_selection_string="--filter tag:$tag"
|
|
;;
|
|
*) echo "If you specify a selection_method (-s selection_method) for selecting EBS volumes you must select either \"volumeid\" (-s volumeid) or \"tag\" (-s tag)." 1>&2 ; exit 64 ;;
|
|
esac
|
|
#creates a list of all ebs volumes that match the selection string from above
|
|
ebs_backup_list_complete=`ec2-describe-volumes --show-empty-fields --region $region $ebs_selection_string 2>&1`
|
|
#takes the output of the previous command
|
|
ebs_backup_list_result=`echo $?`
|
|
if [[ $ebs_backup_list_result -gt 0 ]]
|
|
then echo -e "An error occured when running ec2-describe-volumes. The error returned is below:\n$ebs_backup_list_complete" 1>&2 ; exit 70
|
|
fi
|
|
ebs_backup_list=`echo "$ebs_backup_list_complete" | grep ^VOLUME | cut -f 2`
|
|
#code to right will output list of EBS volumes to be backed up: echo -e "Now outputting ebs_backup_list:\n$ebs_backup_list"
|
|
}
|
|
|
|
create_EBS_Snapshot_Tags()
|
|
{
|
|
#snapshot tags holds all tags that need to be applied to a given snapshot - by aggregating tags we ensure that ec2-create-tags is called only onece
|
|
snapshot_tags=""
|
|
#if $name_tag_create is true then append ec2ab_${ebs_selected}_$date_current to the variable $snapshot_tags
|
|
if $name_tag_create
|
|
then
|
|
ec2_snapshot_resource_id=`echo "$ec2_create_snapshot_result" | cut -f 2`
|
|
snapshot_tags="$snapshot_tags --tag Name=ec2ab_${ebs_selected}_$date_current"
|
|
fi
|
|
#if $purge_after_days is true, then append $purge_after_date to the variable $snapshot_tags
|
|
if [[ -n $purge_after_days ]]
|
|
then
|
|
snapshot_tags="$snapshot_tags --tag PurgeAfter=$purge_after_date --tag PurgeAllow=true"
|
|
fi
|
|
|
|
#if $auto_tag is true, then append Volume=$ebs_selected and Created=$date_current to the variable $snapshot_tags
|
|
if $auto_tag
|
|
then
|
|
snapshot_tags="$snapshot_tags --tag Volume=${ebs_selected} --tag Created=$date_current"
|
|
fi
|
|
|
|
#if $snapshot_tags is not zero length then set the tag on the snapshot using ec2-create-tags
|
|
if [[ -n $snapshot_tags ]]
|
|
then echo "Tagging Snapshot $ec2_snapshot_resource_id with the following Tags:"
|
|
ec2-create-tags $ec2_snapshot_resource_id --region $region $snapshot_tags
|
|
fi
|
|
}
|
|
|
|
date_binary_get()
|
|
{
|
|
#`uname -o (operating system) would be ideal, but OS X / Darwin does not support to -o option`
|
|
#`uname` on OS X defaults to `uname -s` and `uname` on GNU/Linux defaults to `uname -s`
|
|
uname_result=`uname`
|
|
case $uname_result in
|
|
Darwin) date_binary="osx-posix" ;;
|
|
Linux) date_binary="linux-gnu" ;;
|
|
*) date_binary="unknown" ;;
|
|
esac
|
|
}
|
|
|
|
get_purge_after_date()
|
|
{
|
|
#based on the date_binary variable, the case statement below will determine the method to use to determine "purge_after_days" in the future
|
|
case $date_binary in
|
|
linux-gnu) echo `date -d +${purge_after_days}days -u +%Y-%m-%d` ;;
|
|
osx-posix) echo `date -v+${purge_after_days}d -u +%Y-%m-%d` ;;
|
|
*) echo `date -d +${purge_after_days}days -u +%Y-%m-%d` ;;
|
|
esac
|
|
}
|
|
|
|
get_purge_after_date_epoch()
|
|
{
|
|
#based on the date_binary variable, the case statement below will determine the method to use to determine "purge_after_date_epoch" in the future
|
|
case $date_binary in
|
|
linux-gnu) echo `date -d $purge_after_date +%s` ;;
|
|
osx-posix) echo `date -j -f "%Y-%m-%d" $purge_after_date "+%s"` ;;
|
|
*) echo `date -d $purge_after_date +%s` ;;
|
|
esac
|
|
}
|
|
|
|
get_date_current_epoch()
|
|
{
|
|
#based on the date_binary variable, the case statement below will determine the method to use to determine "date_current_epoch" in the future
|
|
case $date_binary in
|
|
linux-gnu) echo `date -d $date_current +%s` ;;
|
|
osx-posix) echo `date -j -f "%Y-%m-%d" $date_current "+%s"` ;;
|
|
*) echo `date -d $date_current +%s` ;;
|
|
esac
|
|
}
|
|
|
|
purge_EBS_Snapshots()
|
|
{
|
|
#snapshot_tag_list is a string that contains all snapshots with either the key PurgeAllow or PurgeAfter set
|
|
snapshot_tag_list=`ec2-describe-tags --show-empty-fields --region $region --filter resource-type=snapshot --filter key=PurgeAllow,PurgeAfter`
|
|
#snapshot_purge_allowed is a list of all snapshot_ids with PurgeAllow=true
|
|
snapshot_purge_allowed=`echo "$snapshot_tag_list" | grep .*PurgeAllow'\s'true | cut -f 3`
|
|
|
|
for snapshot_id_evaluated in $snapshot_purge_allowed
|
|
do
|
|
#gets the "PurgeAfter" date which is in UTC with YYYY-MM-DD format (or %Y-%m-%d)
|
|
purge_after_date=`echo "$snapshot_tag_list" | grep .*$snapshot_id_evaluated'\s'PurgeAfter.* | cut -f 5`
|
|
#if purge_after_date is not set then we have a problem. Need to alert user.
|
|
if [[ -z $purge_after_date ]]
|
|
#Alerts user to the fact that a Snapshot was found with PurgeAllow=true but with no PurgeAfter date.
|
|
then echo "A Snapshot with the Snapshot ID $snapshot_id_evaluated has the tag \"PurgeAllow=true\" but does not have a \"PurgeAfter=YYYY-MM-DD\" date. $app_name is unable to determine if $snapshot_id_evaluated should be purged." 1>&2
|
|
else
|
|
#convert both the date_current and purge_after_date into epoch time to allow for comparison
|
|
date_current_epoch=`get_date_current_epoch`
|
|
purge_after_date_epoch=`get_purge_after_date_epoch`
|
|
#perform compparison - if $purge_after_date_epoch is a lower number than $date_current_epoch than the PurgeAfter date is earlier than the current date - and the snapshot can be safely removed
|
|
if [[ $purge_after_date_epoch < $date_current_epoch ]]
|
|
then
|
|
echo "The snapshot \"$snapshot_id_evaluated\" with the Purge After date of $purge_after_date will be deleted."
|
|
ec2-delete-snapshot --region $region $snapshot_id_evaluated
|
|
fi
|
|
fi
|
|
done
|
|
}
|
|
|
|
app_name=`basename $0`
|
|
|
|
#sets defaults
|
|
selection_method="volumeid"
|
|
|
|
#date_binary allows a user to set the "date" binary that is installed on their system and, therefore, the options that will be given to the date binary to perform date calculations
|
|
date_binary=""
|
|
|
|
#sets the "Name" tag set for a snapshot to false - using "Name" requires that ec2-create-tags be called in addition to ec2-create-snapshot
|
|
name_tag_create=false
|
|
#sets the auto_tagging feature to false - auto_tag creates tags on snapshots - by default each snapshot is tagged with volume_id and current_data timestamp
|
|
auto_tag=false
|
|
#sets the Purge Snapshot feature to false - this feature will eventually allow the removal of snapshots that have a "PurgeAfter" tag that is earlier than current date
|
|
purge_snapshots=false
|
|
#handles options processing
|
|
while getopts :s:c:r:v:t:k:pna opt; do
|
|
case $opt in
|
|
s) selection_method="$OPTARG";;
|
|
c) cron_primer="$OPTARG";;
|
|
r) region="$OPTARG";;
|
|
v) volumeid="$OPTARG";;
|
|
t) tag="$OPTARG";;
|
|
k) purge_after_days="$OPTARG";;
|
|
n) name_tag_create=true;;
|
|
p) purge_snapshots=true;;
|
|
a) auto_tag=true;;
|
|
*) echo "Error with Options Input. Cause of failure is most likely that an unsupported parameter was passed or a parameter was passed without a corresponding option." 1>&2 ; exit 64;;
|
|
esac
|
|
done
|
|
|
|
#sources "cron_primer" file for running under cron or other restricted environments - this file should contain the variables and environment configuration required for ec2-automate-backup to run correctly
|
|
if [[ -n $cron_primer ]]
|
|
then if [[ -f $cron_primer ]]
|
|
then source $cron_primer
|
|
else
|
|
echo "Cron Primer File \"$cron_primer\" Could Not Be Found." 1>&2 ; exit 70
|
|
fi
|
|
fi
|
|
|
|
if [ -z $region ]; then
|
|
if [ -z $EC2_REGION ]; then
|
|
region="us-east-1"
|
|
else
|
|
region="$EC2_REGION"
|
|
fi
|
|
fi
|
|
|
|
#calls prerequisitecheck function to ensure that all executables required for script execution are available
|
|
prerequisite_check
|
|
|
|
#sets date variable
|
|
date_current=`date -u +%Y-%m-%d`
|
|
#sets the PurgeAfter tag to the number of days that a snapshot should be retained
|
|
if [[ -n $purge_after_days ]]
|
|
then
|
|
#if the date_binary is not set, call the date_binary_get function
|
|
if [[ -z $date_binary ]]
|
|
then date_binary_get
|
|
fi
|
|
purge_after_date=`get_purge_after_date`
|
|
echo "Snapshots taken by $app_name will be eligible for purging after the following date: $purge_after_date."
|
|
fi
|
|
|
|
#get_EBS_List gets a list of EBS instances for which a snapshot is desired. The list of EBS instances depends upon the selection_method that is provided by user input
|
|
get_EBS_List
|
|
|
|
#the loop below is called once for each volume in $ebs_backup_list - the currently selected EBS volume is passed in as "ebs_selected"
|
|
for ebs_selected in $ebs_backup_list
|
|
do
|
|
ec2_snapshot_description="ec2ab_${ebs_selected}_$date_current"
|
|
ec2_create_snapshot_result=`ec2-create-snapshot --region $region -d $ec2_snapshot_description $ebs_selected 2>&1`
|
|
if [[ $? != 0 ]]
|
|
then echo -e "An error occured when running ec2-create-snapshot. The error returned is below:\n$ec2_create_snapshot_result" 1>&2 ; exit 70
|
|
else
|
|
ec2_snapshot_resource_id=`echo "$ec2_create_snapshot_result" | cut -f 2`
|
|
fi
|
|
create_EBS_Snapshot_Tags
|
|
done
|
|
|
|
#if purge_snapshots is true, then run purge_EBS_Snapshots function
|
|
if $purge_snapshots
|
|
then echo "Snapshot Purging is Starting Now."
|
|
purge_EBS_Snapshots
|
|
fi |