I really have no idea, but I thought I would toss this out there:
[~]$ nslookup brynmawr.edu
[~]$ nslookup forums.brynmawr.edu
forums.brynmawr.edu canonical name = blog-serv.brynmawr.edu.
Then I remembered this post:
If you search these forums for subdomain and wpmu, you might find something useful. I don’t use WPMU or subdomains, so I am just guessing here.
Just a total guess on my part but it’s probably because your re-write rules are conflicting with the fact that forums.xyz.com is really xyz.com/forums/
when the rewrite rules change the content, it tries to route it to xyz.com/index.php which is wrong and should be xyz.com/forums/index.php
So first, temporarily turn off pretty permalinks in the admin (or via bb-config.php)
Then re-generate the mod-rewrite rules and you may have to hand edit them.
This is completely out of left field with this suggestion, but I had similar problems with the redirection errors like you but I don’t use WPMU so this might not apply.
I honestly can’t remember if I changed any of the chmod settings, I think I might of changed them all the files to 777.
But also in the setup when it asks you in the wordpress integration stage when it asks you to fill in the xxx_xxx_salt settings from the wordpress just leave them blank.
Might help for you.
ck–I can’t even get to the admin panel at this point as the install didn’t create a keymaster account.
benzilla–all my files are 777 and still the issue.
Also, I should note that I got the same error just now when I logged in to *this* site, so it seems like a software problem. I’ll check the known issues area in trac.
What we’ve come up with so far is that in in bb-load.php, there’s a loop happening when installation doesn’t complete. It could be something along the lines of what you mention, ck, in that the location is redirected. I’d change the settings but I don’t see where to do that. I’m going to see what I can do later today and I’ll be sure to post any updates.