running on multiple server instances

[oliverkaiser]

I would like to use this package for a site which will run on multiple ec2 instances of amazon web services behind a load balancer. Now I see two options:

• Integrate the crontab setup within my deploy script to setup the cron on every instance. How do I prevent multiple executions at the same time / overlapping ?
• Setup an external server to call the route from outside and the loadbalancer chooses an instance on which it will be executed. ( I think this could work but isn't that nice in my opinion )

What do you think? What is the way to go?

[liebig]

Hi kaiserlos,

thanks for using Cron. What should the Cron jobs do? Is it necessary that this jobs run on all server instances or can one server handle this?

If you choose your first option, the Cron jobs would be executed multiple because Cron has an overlapping protection but this works on file system basis. To prevent overlapping a database should be used for detecting the Cron run.

Your second option sounds good for me. The overlapping protection would not work either (because of the load balancing) but only one Cron will run on the same time. If your Cron jobs perform heavy load, the load balancing works great here and would choose the best server to execute the jobs. I would prefer this option.

If you have further questions don't hasitate to ask.

Many greetings
Marc