WP-CLI snippets and scripts

wp-db-backup.sh

# Only database backup

declare -a SITES=('site1' 'site2' 'site3' 'site4');

SITES_PATH_BASE=/var/www/
SITES_PATH_SUFIX=/repo/public
SITES_BACKUP_FOLDER=backups

CURRENT_DATE=`date +%Y-%m-%d`;

for SITE in ${SITES[@]} 
do

	echo "";
	echo "Taking backup of ${SITE}..."

	BACKUP_FOLDER=${SITES_PATH_BASE}${SITE}/${SITES_BACKUP_FOLDER};

	# Create backup folder if it does not exist
	if [ ! -d $BACKUP_FOLDER ]; then

		echo "Creating folder ${BACKUP_FOLDER}";
		mkdir -p $BACKUP_FOLDER;

	fi

	BACKUP_FILENAME=${BACKUP_FOLDER}/db_backup-${CURRENT_DATE}.sql; 

	# Export db and save the backup relative to the public dir
	wp db export ${BACKUP_FILENAME} --path=${SITES_PATH_BASE}${SITE}${SITES_PATH_SUFIX} --allow-root;

done

wp-maintenance.sh

# Backups files and databases + updating WordPress and plugins with extra paramter ( "./wp-maintenance.sh update" )

declare -a SITES=('site1' 'site2' 'site3' 'site4');

SITES_PATH_BASE=/var/www/
SITES_PATH_SUFIX=/repo/public
SITES_BACKUP_FOLDER=backups

CURRENT_DATE=`date +%Y-%m-%d`;

PARAM1=$1;

for SITE in ${SITES[@]} 
do

	SITE_PUBLIC_DIR=${SITES_PATH_BASE}${SITE}${SITES_PATH_SUFIX}

	echo "";
	echo "Taking backup of ${SITE}..."

	BACKUP_FOLDER=${SITES_PATH_BASE}${SITE}/${SITES_BACKUP_FOLDER};

	# Create backup folder if it does not exist
	if [ ! -d $BACKUP_FOLDER ]; then

		echo "Creating folder ${BACKUP_FOLDER}";
		mkdir -p $BACKUP_FOLDER;

	fi

	echo "Backing up the database..."
	SQL_BACKUP_FILENAME=${BACKUP_FOLDER}/${SITE}_db_backup-${CURRENT_DATE}.sql; 

	# Export db and save the backup relative to the public dir
	wp db export ${SQL_BACKUP_FILENAME} --path=${SITE_PUBLIC_DIR} --allow-root;

	echo "Backing up the files..."
	FILE_BACKUP_FILENAME=${BACKUP_FOLDER}/${SITE}_file_backup-${CURRENT_DATE}.tar.gz; 
	tar -czpf ${FILE_BACKUP_FILENAME} -C ${SITE_PUBLIC_DIR} .;

	echo "Files backup saved to ${FILE_BACKUP_FILENAME}";

	echo "Backup completed";

	if [ "${PARAM1}" == "update" ]; then 

		echo "Updating WordPress...";
		wp core update --path=${SITE_PUBLIC_DIR}  --allow-root;

		echo "Updating plugins...";
		wp plugin update --all --path=${SITE_PUBLIC_DIR}  --allow-root;

	fi

	echo "Done";
	echo "";

done

First configure SITES_PATH_BASE, SITES_PATH_SUFIX and SITES_BACKUP_FOLDER to reflect you environment and your preferences.
Then the SITES variable on the first line. This should contain the folder names to the sites you want to backup.
Then add the script to cron.

This example takes DB backup of the following sites:
/var/www/site1/repo/public/
/var/www/site2/repo/public/
/var/www/site3/repo/public/
/var/www/site4/repo/public/

And saves backups in (respectively):
/var/www/site1/backups/db_backup-{date}.sql
/var/www/site2/backups/db_backup-{date}.sql
/var/www/site3/backups/db_backup-{date}.sql
/var/www/site4/backups/db_backup-{date}.sql

To run the script just run ./wp-maintenance.sh or /path/to/script/wp-maintenance.sh

To update, simple add "update" after the command, like this: "./wp-maintenance.sh update"