Create directories

_$: mkdir -p /srv/backup/logs
_$: cd /srv/backup/logs
_$: for i in <website 1> <website 2> <website N>
do
    mkdir -p ./$i/{web,app}
    chown --recursive root:backupgroup ./$i
    chmod --recursive g+rwx ./$i
done

Delete old files

/root/cron/log-clean.sh:
------------------------
LOGPATH="/srv/logs"

delete_older_than() {
    # Arguments: path and age (in days)
    if [ $# -ne 2 ]
    then
        printf "Not enough arguments\n"
        exit 1
    else
        printf "Deleting all files older than $2 days in $1\n"
        find $1 -type f -mtime +$2 -exec echo {} \;
        find $1 -type f -mtime +$2 -exec rm {} \;
    fi
}

# Delete old files
delete_older_than ${LOGPATH}/web_1   30
delete_older_than ${LOGPATH}/web_2   30

Add to crontab

MAILTO="david@tenfox.com"
00  09  *   *   *     /root/cron/database-backup.sh
15  09  *   *   *     /root/cron/database-clean.sh
20  09  *   *   *     /root/cron/log-clean.sh