via Deploy Hook
UPDATE 4.10.2013: Updating these instructions to use bundle exec, per chintan/Nic Pillinger
UPDATE 11.4.2013: Updating these instructions to use helper methods to determine which instances to run the command on
If you want your crontab updated by whenever on deploy, make a file named deploy/before_restart.rb and stick this in it:
on_app_master do
# the following updates the crontab upon deployment
run "cd #{config.release_path}; bundle exec whenever --set environment=#{config.framework_env} --update-crontab '#{config.app}_#{config.framework_env}'"
end
This is called a ‘deploy hook’ and here’s more info.
via Deploy Hook using Binstubs
Since Engine Yard automatically installs your binstubs, you could also replace “bundle exec whenever” with “ey_bundler_binstubs/whenever”. If you want to be able to run “bin/whenever” you’ll have to symlink to ey_bundler_binstubs – but remember it’s in the current deploy directory, so you’ll have to do this per-deploy – which means you could stick this in the same before_restart.rb file (obviously it would need to be above the whenever block):
run "ln -nfs #{config.release_path}/ey_bundler_binstubs #{config.release_path}/bin"
on_app_master do
# the following updates the crontab upon deployment
run "cd #{config.release_path}; bin/whenever --set environment=#{config.framework_env} --update-crontab '#{config.app}_#{config.framework_env}'"
end
Note for Utility Instances
UPDATE 11.4.2013: If you also want your cron jobs to work on all app servers (not just your app master), change “on_app_master” above to “on_app_servers”. For app servers and utilities, use “on_app_servers_and_utilities”. For utilities only, use “on_utilities”. As far as I can tell, there does not appear to be an option for only app master and utilities; if you need this, write two identical blocks with “on_app_master” and “on_utilities”.
via Custom Chef Recipes
Why would you also need to do a custom chef recipe? Because if you rebuild your cluster and don’t redeploy, your cron jobs won’t be created.
UPDATE 4.17.2012: If you’re on EY and not using custom chef recipes, you should start. A whenever recipe has been written and is detailed here. Info on how to start using custom chef recipes is here. It’s not so bad, really. One gotcha: your “appname” in the recipe is not your rails application name, but your EY application name – these can be different things!
Sara Trice 
July 19, 2012 at 9:28 am
cant you use bundle exec such as :
run “cd #{release_path}; bundle exec whenever –set environment=#{@rails_env}; bundle exec whenever –update-crontab ‘yourAppNameHere'”
with bundle exec there is no need for step 1) install gem whenever
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July 19, 2012 at 10:06 am
Sure you can… but since using custom chef is a better option here (for engine yard) I updated the post to advise using that instead.
Always more than one way to do it.
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November 6, 2012 at 5:42 pm
Hi Sara, Thanks for the post. Secondary note for your readers just in case they need a reminder. If you only want this to run on a util server be sure to wrap the above deploy hook stuff with current_role == ‘util’.
Cheers and Thanks again.
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April 10, 2013 at 10:16 am
first of all, thanks for this – helped sort my crontab/whenever problems out. secondly – chintan is correct above – you shouldn’t be installing any gems on your EY instances even in a chef recipe.
Using bundle exec means you’ll get the version of whenever you have bundled with your app and is the correct way to solve this problem.
cheers
Nic
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April 10, 2013 at 10:47 am
Thanks, Nic. I’ve updated the post entirely to account for all the new info I’ve learned since Sep 2011.
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April 23, 2013 at 11:00 am
Thanks for the update….Here is my deploy hook (that works) on ey solo instance for reference:
In before_restart.rb:
@rails_env = node[:environment][:framework_env]
run “cd #{release_path}; bundle exec whenever –set environment=#{@rails_env} –update-crontab fleetapp”
Also, as pointed out be sure to wrap this in current_role == ‘util’ stuff for a cluster setup.
Thanks
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