问题
We have a large deployment of around a dozen servers. We'd like to use the Whenever gem but I can't figure out a way to say which machine the cron jobs should go on! We only want these jobs to run on our server that does background jobs.
Is there a way to specify this?
回答1:
If you deploy the project with Capistrano and you use the default Whenever recipe, you can create a new Capistrano role
role :whenever, "192.168.1.1"
and set the role in your deploy.rb file
set :whenever_roles, "whenever"
In this way, the task will be executed only on the specified server.
回答2:
whenever is preconfigured to run against the db role, so if your db role is also the background machine's role you don't have to do the 'role :whenever, "192.168.0.1"' hack. see the codes
https://github.com/javan/whenever/blob/master/lib/whenever/capistrano.rb#L2
来源：https://stackoverflow.com/questions/5065109/whenever-gem-have-cronjob-on-only-one-machine