backup-monthly

#!/bin/bash

# This script rotates the oldest weekly backup
# to monthly backup.

BACKUP_VOLUME=$1
BACKUP_MOUNT=$2
BACKUP_DEVICE="${BACKUP_VOLUME}"
BACKUP_RW_MOUNT="${BACKUP_MOUNT}/${BACKUP_VOLUME}_rw"
BACKUP_RO_MOUNT="${BACKUP_MOUNT}/${BACKUP_VOLUME}"

./make_backup_rw ${BACKUP_VOLUME} ${BACKUP_MOUNT} || exit 1

### Delete the oldest monthly backup, if it exists
#
if [ -d ${BACKUP_RW_MOUNT}/monthly.3 ] ; then
rm -rf ${BACKUP_RW_MOUNT}/monthly.3
fi

### Shift the middle snapshots(s) back by one, if they exist
if [ -d ${BACKUP_RW_MOUNT}/monthly.2 ] ; then
mv ${BACKUP_RW_MOUNT}/monthly.2 ${BACKUP_RW_MOUNT}/monthly.3 ;
fi
if [ -d ${BACKUP_RW_MOUNT}/monthly.1 ] ; then
mv ${BACKUP_RW_MOUNT}/monthly.1 ${BACKUP_RW_MOUNT}/monthly.2 ;
fi
if [ -d ${BACKUP_RW_MOUNT}/monthly.0 ] ; then
mv ${BACKUP_RW_MOUNT}/monthly.0 ${BACKUP_RW_MOUNT}/monthly.1 ;
fi

### Hard link oldest weekly backup to monthly backup
#
if [ -d ${BACKUP_RW_MOUNT}/weekly.0 ] ; then
cp -al ${BACKUP_RW_MOUNT}/weekly.3 ${BACKUP_RW_MOUNT}/monthly.0
fi

./make_backup_ro ${BACKUP_VOLUME} ${BACKUP_MOUNT}