Cron

cron and backups

php www-data program that creates a crontab and calls a C program that executes root commands to copy it into crontabs and install it

current crontab in /var/spool/cron/crontab/pathbost <syntaxhighlight>

1. m h dom mon dow command
2. backup MYSQL databases every 4 days (starting at 3:00AM)

00 3 */4 * * cd /home/sitebuil/scripts/S3-Site-Backups; php s3cli_backupDb.php sitebuil_wikidb 05 3 */4 * * cd /home/sitebuil/scripts/S3-Site-Backups; php s3cli_backupDb.php sitebuil_wrdp1 10 3 */4 * * cd /home/sitebuil/scripts/S3-Site-Backups; php s3cli_backupDb.php sitebuil_wuffdb 15 3 */4 * * cd /home/sitebuil/scripts/S3-Site-Backups; php s3cli_backupDb.php taxplans 20 3 */4 * * cd /home/sitebuil/scripts/S3-Site-Backups; php s3cli_backupDb.php webeshoppin

1. Delete all local backups older than 3 weeks (at 2am)

00 2 * * * find /var/backups/backup/*.gz -ctime +21 -type f -print | xargs rm -f </syntaxhighlight> crontab to delete files older than 21 days

#Delete all local backups older than 3 weeks (at 2am)
00 2 * * * find /PATH/TO/HOME_DIR/backups/*.gz -ctime +21 -type f -print | xargs rm -f
#Run it every three days...
0 0 */3 * *

cron tutorial another

Re: Where is crontab stored?

Root-level crontab should be in /etc/crontab.

Root-level anacron and periodics should be in /etc/cron*

User-level crontabs should be in /var/spool/cron/crontabs - they are listed by user, pathbost isactually a chrontab

select-editor

installing and testing a crontab

installing

even after you change it by yourself you can install it by running as root

sudo crontab -u pathbost /var/spool/cron/crontabs/pathbost

testing

* * * * * /bin/echo " pathGZoobar $(date) " >> /usr/local/docs/testcron.txt

will append this every minute to testcron.txt

 pathGZoobar Thu Jan  3 14:15:01 EST 2013

You can check the logs to see if the crontab got installed/executed by running as root

sudo tail /var/log/syslog

vi with crontab 101

• su to user then 'crontab -e'
• 'i' to insert text
• 'esc :wq to save change, and quit
  • then crontab is installed
• 'esc :q!' exits without saving (or installing)
• you can kill your crontab with crontab -r
• you can list the installed crontab with crontab -l

backup to s3

Backups have a 30 day life on s3 and a 21 day life in /var/backups/backup backup_to_S3 code

directory backup

To backup a directory run this from the terminal:

sudo php /home/sitebuil/scripts/S3-Site-Backups/s3cli_backupDir.php /home/sitebuil/public_html/doku doku

database backup

sudo php php /home/sitebuil/scripts/S3-Site-Backups/s3cli_backupDb.php sitebuil_wiki

or goto http://pathboston.com/zstill/stillwater.html

refs

• http://www.cenolan.com/2008/05/simple-linux-to-amazon-s3-backup-script/
• http://www.alvechurchdata.co.uk/softhanoi.htm
• http://s3tools.org/s3cmd
• http://tagmycode.com/snippet/480/backup-mysql-database-to-amazon-s3-with-s3cmd-on-debian#.UMifCoP2GSo
• http://docs.amazonwebservices.com/AmazonS3/latest/dev/object-lifecycle-mgmt.html
• http://en.wikipedia.org/wiki/Backup_rotation_scheme
• http://net.tutsplus.com/tutorials/php/managing-cron-jobs-with-php-2/

s3 backup with s3napback

string meaning

   ------ -------
   @reboot Run once, at startup
   @yearly Run once a year, "0 0 1 1 *"
   @annually (same as @yearly)
   @monthly Run once a month, "0 0 1 * *"
   @weekly Run once a week, "0 0 * * 0"
   @daily Run once a day, "0 0 * * *"
   @midnight (same as @daily)
   @hourly Run once an hour, "0 * * * *"