So now we have our backup script, we have our secure SSH tunnel between the two servers and we have successfully synced our two databases and our files. Now we just have to schedule this task so that we do not have to manually run this each time we need to synchronize our systems. On Mac OSX Servers you have two options you can use Crontab and run a Cronjob, or you can use Launchd. If your running a Linux server then your pretty limited to just a Cronjob. We will talk about both types of scheduling methods and which one makes the best sense for your setup.

Crontab is one of the longest lasting scheduling daemons around, its part of any linux / unix system and uses a file that will trigger a script at a specific time at specific intervals. Cron can be pretty amazing but pretty daunting too if you are unsure about how to use cron, I recommend starting out easy and using this GUI for Mac OSX called Cronnix.

Cronnix is a great tool because it lets you modify, save and create crontab cronjobs in a very easy to use interface. Before Cronnix you basically had to use the VI editor in order to edit the crontab file manually which did not always prove successful. Once your ready to make your first schedule then you need to know what time or at what intervals you want the backup to run. I had my backup script run at midnight every-night so my crontab looked like this.

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0 0 * * * /bin/bash /path/to/my/sync/script.sh

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