From FarmShare

There is now AFS available on the barley machines. You'll want to ensure you have your Kerberos ticket first, use 'klist' and 'kinit' for that. Next, you'll want to ensure you have your AFS tokens, you can use 'tokens' to list them or 'aklog' to get them.

Then you can just submit jobs to the resource manager, and the jobs will be able to read/write to/from your AFS directories.