DZone Snippets: cron code

Rip an Icecast stream

jrobertson (James Robertson) — Sun, 21 Oct 2007 23:28:15 GMT

Rip an Icecast stream (for a 30 min duration), and direct the streamripper text including errors to /dev/null. Note: Directing the output to null is necessary when running this within a cron job.



streamripper http://192.168.1.7:8000/radio_x.ogg.m3u -dq  ~james/Streamripper_rips/hay -a %d -l 1800 >/dev/null 2>&1

truncate Rails development/test logs

laurelfan (Laurel Fan) — Tue, 07 Aug 2007 17:17:16 GMT

In rails applications development.log and test.log like to grow forever, which takes up space and makes them slow to grep. If I just delete them running processes with logs open might get confused. So I can use truncate instead:



truncate ~/www/*/log/*.log

Even easier, ask cron to do it for me every night:



4 22 * * * * truncate -s 0k  ~/www/*/log/*.log

Simple mySQL backup script for cron

fak3r (fak3r) — Wed, 20 Jun 2007 15:01:39 GMT

Simple mySQL backup script for cron - backs up all databases, saves the last 4 copies.



#!/bin/bash



# modify the following to suit your environment

export DB_BACKUP="/backup/mysql_backup"

export DB_USER="root"

export DB_PASSWD="********"



# title and version

echo ""

echo "mySQL_backup"

echo "----------------------"

echo "* Rotating backups..."

rm -rf $DB_BACKUP/04

mv $DB_BACKUP/03 $DB_BACKUP/04

mv $DB_BACKUP/02 $DB_BACKUP/03

mv $DB_BACKUP/01 $DB_BACKUP/02

mkdir $DB_BACKUP/01 



echo "* Creating new backup..."

mysqldump --user=$DB_USER --password=$DB_PASSWD --all-databases | bzip2 > $DB_BACKUP/01/mysql-`date +%Y-%m-%d`.bz2

echo "----------------------"

echo "Done"

exit 0

Backup MySQL databases into seperate files

mixonic (Matthew Beale) — Tue, 20 Dec 2005 12:50:04 GMT

A cronable script for backing up all your databases as seperate files. I'd suggest limiting the backup user's access to the IP of the computer backing up, and using some sort of encryption if you're on a capable version of mysql.



#!/bin/sh

#

# MySQL backups from the Data



MOUNTED=`grep /etc/mtab -e \/mnt\/backup`

if [ "$MOUNTED" = '' ]; then

        echo "/mnt/backup is not mounted, there is no drive to backup to"

        exit 1

fi





mkdir -p /mnt/backup/cluster_sql



for i in $(echo 'SHOW DATABASES;' | mysql -ubackup -pSUPERSECRET -hData|grep -v '^Database$'); do

  mysqldump -ubackup -pSUPERSECRET -hData --opt $i > /mnt/backup/cluster_sql/$i.sql;

done;

Automatically erase Ruby on Rails session files

peter (Peter Cooperx) — Fri, 16 Sep 2005 22:53:51 GMT

Add to your cron:

1 */4 * * * find /tmp/ -name "ruby_sess*" -cmin +600 -exec rm \{} \;

Deletes sessions over ten hours old every four hours. Otherwise your /tmp will end up overflowing. This only applies you use the file store method of session storage with Rails.