Referance Articles : http://www.smiss.com.ua/blog/how-make-automatic-snapshots-using-google-compute-engine and https://cloud.google.com/compute/docs/gcutil/

Objective : how-make-automatic-snapshots-using-google-compute-engine

Snapshots are used for Backup purpose . This document talks about how to create automatic backups i.e Snapshot Backup

Process

login to the google cloud compute engine and look for "gcutil" via locate command

If Not available then Install gcutil as below

Install gcutil

To install gcutil:

Download gcutil-1.16.1.tar.gz file.

wget https://dl.google.com/dl/cloudsdk/release/artifacts/gcutil-1.16.1.tar.gz

Extract the files.

Run the following command to extract the tar file. This unpacks a directory named gcutil-1.16.1 in /usr/local/share.

sudo tar xzvpf gcutil-1.16.1.tar.gz -C /usr/local/share

Create a symbolic link to the gcutil binary.

sudo ln -sf /usr/local/share/gcutil-1.16.1/gcutil /usr/local/bin/gcutil

Start using gcutil.

If you modified your system path, restart your shell before continuing so the changes can take effect. To see a list of available gcutil commands, run:

$ gcutil help

For additional information on authenticating with the Cloud SDK, such as if you are working in a terminal session on another machine, see the following section.

Authenticate gcutil

To authenticate gcutil, follow the instructions for gcloud compute.

Then, test out the tool by running:

$ gcutil listinstances

Once gcutil has been installed please proceed with the script now

Automated Backup Script

Create a script as /root/scripts/gsnapshots.sh ( make sure you do make it executable ) the Script is below . The parameter to be looked upon are

Mailboxes - email address to which alert mail should go

GCUTILPATH - the path of gcutils

project - this is google project name , it has to be go from Mr Banerjee

list - List of disk which need to be backup , run the command

gcutil --project="aimil-zimbra" listdisks --format=csv
name,zone,status,size-gb
disk-1,asia-east1-a,READY,500
instance-1,asia-east1-a,READY,20

so there are 2 disk , disk-1 and instance-1

days - No of days for rotation of snapshot backups

The script /root/scripts/gsnapshots.sh as follows

#!/bin/bash
# Google cloud snapshots script.
#list of mailboxes
mailboxes="biswajit@tetrain.com"
mailtext=/tmp/mailtext$$
# GCUTILPATH
GCUTILPATH=/usr/local/bin/
# Project name
project=aimil-zimbra
# What need to backup, list - disks from list, all - all disks.
backup="all"
#List of persistent disks
list="disk-1 instance-1"
# Rotation, how many days  to keep
days=30
##############################################################################
log()
{
	echo `date +%y/%m/%d_%H:%M:%S`:: $* >> $mailtext
	echo `date +%y/%m/%d_%H:%M:%S`:: $*
}
case $backup in
           	"all" )
           	disklist=`${GCUTILPATH}gcutil --project="$project" listdisks --format=csv | tail -n +2 | cut -d ',' -f1`
           	;;
           	"list")
           	disklist=$list
           	;;
           	*)
           	log "Nothing to backup"
           	exit 0
           	;;
esac
function test {
       "$@"
	local status=$?
       if [ $status -ne 0 ]; then
   	echo "error with $1"
   	mail -s "GOOGLE snapshot backup, ERROR. "  $mailboxes < $mailtext
   	exit $status
	fi
	return $status
}
for i in $disklist
do
log "Starting snapshot for $i"
test ${GCUTILPATH}gcutil --service_version="v1"  --project="$project" addsnapshot "$i""-`date +%y%m%d`" --source_disk="$i"
log "Snapshot for $i finished"
done
#Rotation
for i in $disklist
do
snapshot="$i""-`date +%y%m%d -d "$days day ago"`"
exist=`${GCUTILPATH}gcutil --project="$project" listsnapshots --format=csv | grep $snapshot`
   	if [ -z $exist ];then
   	log "Warning, snapshot $snapshot was not found"
   	else
   	log "Starting rotation for $i"
   	test ${GCUTILPATH}gcutil --project="$project" deletesnapshot -f $snapshot
   	log "Rotation for $i finished"
   	fi
done
log "All done."
test rm $mailtext