restic-backup.sh

#!/usr/bin/env bash
# Written by: Daulton
# Website: https://daulton.ca
# Github: https://github.com/jeekkd
# License: 2-clause BSD license
# Purpose: Script Restic backups for myself, only meant for me but modify it if its useful to you.
# Notes: Assure Restic and Swaks is installed.

# BSD 2-Clause License
# 
# Copyright (c) [2022], [backup-restic.sh]
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
# 
# 1. Redistributions of source code must retain the above copyright notice, this
#    list of conditions and the following disclaimer.
# 
# 2. Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

######## Variables ########
# Restic repo password, same for each repo
export RESTIC_PASSWORD=

# Backup the following directory
backupDirList=/home/you/Important/

# S3 bucket path
s3Bucket="https://example.com/example"

# B2 bucket name
B2Bucket=

# Minio S3 storage access
# https://restic.readthedocs.io/en/stable/030_preparing_a_new_repo.html#amazon-s3
export AWS_ACCESS_KEY_ID=
export AWS_SECRET_ACCESS_KEY=

# B2 storage access
# https://restic.readthedocs.io/en/stable/030_preparing_a_new_repo.html#backblaze-b2
export B2_ACCOUNT_ID=
export B2_ACCOUNT_KEY=

# Mount point for second disk
mountPoint=/mnt/data

# Secondary disk to mount
secondaryDisk=/dev/sdb1

# Local mount point Restic repository name
localRepoName=restic-repo

# SMTP server hostname
smtpHostname=example.com

# Email account sending as
smtpFrom=sender@example.com

smtpFromPassword=

# Send email to the following account
smtpTo=you@example.com

###########################

# control_c()
# Trap Ctrl-C for a quick and clean exit when necessary
control_c() {
	echo "Control-c pressed - exiting NOW"
	exit 1
}

# Trap any ctrl+c and call control_c function provided through functions.sh
trap control_c INT

# Exit and send email alert if error
check_exit_code_email() {
	if [ $? -ne 0 ]; then
		echo "Warning: Fatal error or source files could not be read."
		echo "Exit code: $?"
		swaks --to "$smtpTo" --from "$smtpFrom" -s "$smtpHostname":587 -tls -au alerts@tetmail.ca -ap "$smtpFromPassword" --header "Subject: Restic backup error" --body ~/restic.log > /dev/null 2>&1
		exit 1
	fi
}

# Check if local disk is mounted as read-only.
check_if_drive_ro() {
	diskCheckResult=$(grep "[[:space:]]ro[[:space:],]" /proc/mounts | grep "$mountPoint")
	[ "$diskCheckResult" = "" ]  && return 3
}

# Redirect stdout ( > ) into a named pipe ( >() ) running "tee"
exec > >(tee -i restic.log)

# Without this, only stdout would be captured - i.e. your
# log file would not contain any error messages.
# SEE (and upvote) the answer by Adam Spiers, which keeps STDERR
# as a separate stream - I did not want to steal from him by simply
# adding his answer to mine.
exec 2>&1

echo "Backup beginning at: $(date)"
echo

# Check if Restic is already running
check_process() {
  [ "$1" = "" ]  && return 0
  [ $(pgrep -n $1) ] && return 1 || return 0
}

check_process "restic"
if [ $? -eq 1 ]; then
	echo "Warning: Restic already running, exiting.."
	exit 1
else
	echo "Information: Another instance of Restic is not currently running, continuing."
fi

run_restic_local() {
	echo "###"
	echo "# Local backup to second HDD"
	echo "###"
	echo

	restic -r "$mountPoint"/"$localRepoName" --verbose backup "$backupDirList"
	check_exit_code_email
	restic -r "$mountPoint"/"$localRepoName" forget --keep-hourly 6 --keep-daily 14 --keep-weekly 4 --keep-monthly 3
	restic -r "$mountPoint"/"$localRepoName" check
	check_exit_code_email
	echo
}

mount | grep -q "[[:space:]]$mountPoint[[:space:]]"
if [ $? -eq 0 ]; then
    check_if_drive_ro
	if [ $? -ne 3 ]; then
		echo "Notice: Local disk is mounted ro, repairing.."
		sudo umount -f "$mountPoint"
		if [ $? -eq 0 ]; then
			sudo ntfsfix "$secondaryDisk"
			sudo ntfs-3g "$secondaryDisk" "$mountPoint"
			if [ $? -eq 0 ]; then
				run_restic_local
				check_exit_code_email
			fi
		else
			check_exit_code_email
			echo "Critical: Unable to umount local disk to remount as rw, exiting."
		fi

	else
		echo "Information: The path $mountPoint is already mounted, doing nothing"
    	run_restic_local
		check_exit_code_email
	fi
else
	echo "Notice: Mounting local disk at $mountPoint"
	sudo ntfsfix "$secondaryDisk"
	sudo ntfs-3g "$secondaryDisk" "$mountPoint"
	if [ $? -eq 0 ]; then
		run_restic_local
		check_exit_code_email
	fi
fi

echo "###"
echo "# Backup to Minio on TrueNAS"
echo "###"
echo

restic -r s3:"$s3Bucket" --verbose backup "$backupDirList"
check_exit_code_email
restic -r s3:"$s3Bucket" forget --keep-hourly 6 --keep-daily 14 --keep-weekly 4 --keep-monthly 3
restic -r s3:"$s3Bucket" check
check_exit_code_email

echo
echo "###"
echo "# Backup to Backblaze B2"
echo "###"
echo

restic -r b2:"$B2Bucket" --verbose backup "$backupDirList"
check_exit_code_email
restic -r b2:"$B2Bucket" forget --keep-hourly 6 --keep-daily 14 --keep-weekly 4 --keep-monthly 3
restic -r b2:"$B2Bucket" check
check_exit_code_email
echo