SSH: Rotate backup shell script to remove directories (old backup files)

Most time you have a limited space on the remote SFTP/ SSH backup server. Here is the script that periodically cleanup old backup files from the server i.e it will remove old directories.

Requirements

Script will automatically calculate date from today’s date. By default it will keep only last 7 days backup on server. You can easily increase / decrease this limit. In order to run script you must meet the following criteria:

• Remote SSH server with rm command execution permission
• SSH Keys for password less login (see how to setup RSA / DSA keys for password less login)
• Accurate date and time on local system (see how to synchronize clock using ntpdate ntp client)
• Remote backup directory must be in dd-mm-yyyy or mm-dd-yyyy format. For example daily mysql backup should be stored in /mysql/mm-dd-yyyy format.

Sample Script Usage

Run the script as follows:
./rot.backup.sh 7 /mysql "rm -rf"
Where,

• 7 : Remove last 7 days files
• /mysql : Base directory to clean up. If todays date is 9/Oct/2007, it will remove last 7 days directory /mysql/02-10-2007, /mysql/01-10-2007, …. /mysql/26-09-2007, /mysql/25-09-2007. It means script will only keep last 7 days backup on remote sftp / ssh server.
• rm -rf : Command to run on directory structure

Sample Shell Script

Install following script:

#!/bin/bash
if [ "$#" == "0" ];then
  echo "$0 upper-limit path {command}"
  exit 1
fi
### SSH Server setup ###
SSH_USER="vivek"
SSH_SERVER="nas.nixcraft.in"
START=7
DIR_FORMAT="%d-%m-%Y" # DD-MM-YYYY format
#DIR_FORMAT="%m-%d-%Y" #MM-DD-YYYY format
## do not edit below ##
LIMIT=$( expr $START + $1 )

## default CMD ##
CMD="ls"
SSH_PATH="."

[ "$3" != "" ] && CMD="$3" || :
[ "$2" != "" ] && SSH_PATH="$2" || :

DAYS=$(for d in $(seq $START $LIMIT);do date --date="$d days ago" +"${DIR_FORMAT}"; done)
for d in $DAYS
do
  ssh ${SSH_USER}@${SSH_SERVER} ${CMD} ${SSH_PATH}/$d
done

Run above script via cron tab (cronjob):
@daily /path/to/rot.ssh.script 7 "/html" "rm -rf"
@daily /path/to/rot.ssh.script 7 "/mysql" "rm -rf"