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@asvignesh
Created March 8, 2020 14:51
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Create EC2 Consistent Backup
#!/bin/bash
# ec2-consistentbackup --description='My First backup' --tags="user=asvignesh;"
# This script freezes all EXT4 and XFS Filesystem running on Linux EC2 Instances
description=""
tags=""
for i in "$@"
do
case $i in
--description=*) description="${i#*=}" ;;
--tags=*) tags="${i#*=}" ;;
*) ;;
esac
done
if [[ -z $tags ]]; then
tags_spec=""
else
# Input format is name=value;name2=value2
# Output format is {Key=name,Value=value},{Key=name2,Value=value2}
new_tags=$( echo $tags | perl -p -e 's/(.*?)=(.*?)(;|$)/{Key=\1,Value=\2},/g; s/,$//' )
tags_spec="ResourceType=snapshot,Tags=[$new_tags]"
fi
# Unfreeze file systems
function unfreeze() {
for target in $(findmnt -nlo TARGET -t ext4,xfs); {
if [[ "$target" != "/" ]]; then
fsfreeze --unfreeze "$target";
fi
}
}
function warn_and_unfreeze() {
# If there was any problem, make sure to unfreeze the filesystems before quitting!
errorCode=$?
if [ $errorCode -ne 0 ]; then
unfreeze
echo -e "ec2-consistent-snapshot exited with an error: $snapshot_output\n$vol_output"
exit $errorCode
fi
}
# Make sure to unfreeze if we are done, but but also if there was an error or if we are interrupted
trap warn_and_unfreeze SIGINT ERR
# Sync data to disk
sync
{
# Find the volumes for the instance
instance=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)
# Get the Availability Zone, like "us-east-1b"
az=$(curl -s http://169.254.169.254/latest/meta-data/placement/availability-zone)
# Trim off the last character of the AZ, so "us-east-1b" becomes "us-east-1"
region=${az::-1}
volumes=$(
aws ec2 describe-instance-attribute --instance-id $instance \
--attribute blockDeviceMapping \
--output text \
--query BlockDeviceMappings[*].Ebs.VolumeId \
--region $region
)
# Find the mounted EXT4 and XFS partitions and freeze them
# To avoid hanging the machine in unrecoverable way, don't freeze "/".
for target in $(findmnt -nlo TARGET -t ext4,xfs); {
if [[ "$target" != "/" ]]; then
fsfreeze --freeze "$target";
fi
}
snapshot_output=""
# Create snapshots for the current instance
# Be sure you have an Role attached to the instance
# and that the role has permission to make snapshots.
for volume in $(echo $volumes | tr " " "\n"); {
vol_output=$(
aws ec2 create-snapshot --volume-id $volume \
--description "$description" \
--region $region \
--tag-specifications "$tags_spec" 2>&1
)
snapshot_output="$snapshot_output\n$vol_output";
}
unfreeze
}
exit 0;
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "1",
"Effect": "Allow",
"Action": [
"ec2:CreateSnapshot",
"ec2:CreateTags",
"ec2:DescribeInstanceAttribute"
],
"Resource": [
"*"
]
}
]
}
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