There's a guide for dummies if you want to point to foo.com or www.foo.com. I'm interested to find out how to point a sub-domain such as abc.foo.com to foo.stackexchange.com in GoDaddy. I'm running my own dedicated server.
CNAME method alone didn't propagate even though I set it up the night before and checked my site the following morning. Adding A record- breaks my whole site and stops "named" service


This is what I have in Site Rules. Is it correct? Do I need to point my main site; foo.com and www.foo.com. I'm basically trying to achieve what answers.onstartups.com was able to do.

1st UPDATE It seems a minor "." added at end of 1bny-se.fogcreek.com solved the forwarding issue. See answers/comments below. It's been a day now and I still don't see abc.foo.com masking foo.stackexchange.com. According to my site rules, my primary domain is what the users are ONLY supposed to see. Am I missing something? Suggestions appreciated.
2nd UPDATE Seems after above changes are in place, you must re-publish the primary domain. Click the "Publish" button under Primary Domain. If you end up losing your admin privileges as I did, follow this instructions or get in touch with customer service and request admin upgrade privileges.