Clarification / Confirmation needed re: FreeRadius against Active Directory

[Moe, John]

I'm setting up an Ubuntu server (10.04LTS amd64) with FreeRadius (v2.1.8
from apt-get) to use as an authenticator against Active Directory for
our HP ProCurve switches.  I've gotten the server on to our Active
Directory domain, and have begun the setup of the FreeRadius server.
I've even managed to allow login to a test ProCurve switch using my AD
username.

Now, I've read a lot of configuration pages (for Ubuntu, Samba, Winbind,
and FreeRadius, to name a few) in the last few days, and my head's
spinning a bit, and I'd like to make sure I'm doing this right, and I've
managed to grasp a few things...

Should I be using ntlm_auth, or mschap as my Auth-Type for the ProCurve
switches?  Currently, I'm using:

# HP ProCurve Switch
DEFAULT Auth-Type = ntlm_auth, NAS-Port-Type == Virtual, Service-Type ==
NAS-Prompt-User
        Service-Type = 6

as my line in the "users" file, and it works, but I want to make sure
it's a) doing what I think it's doing, and b) the right way to do it.

>From some of my reading, it seemed to indicate that Auth-Type shouldn't
need to be set, that FreeRadius should be able to figure it out, but if
I leave it out, it appears to match the rest of the rule (NAS-Port-Type
and Service-Type), but I get a message saying:

Tue Mar  1 09:54:03 2011 : Info: No authenticate method (Auth-Type)
configuration found for the request: Rejecting the user
Tue Mar  1 09:54:03 2011 : Info: Failed to authenticate the user.

I've put a single "=" in for the Auth-Type, because the documentation
seems to say that with "=", it'll only add that to the request if no
other Auth-Type was previously set, so that seems to say that the
ProCurve switch isn't requesting ntlm_auth.  How is FreeRadius supposed
to figure it out, then?

Also, I'd like to match the rule (or are they called policies?) against
an Active Directory group name, so that only members of a specific group
can get access into the switch.  I can't seem to find any way match for
that; is it possible?

Any help or pointers would be appreciated.  Thanks.

John H. Moe
Network Support - Hatch IT
HATCH
Tel: +61 (7) 3166 7777
Direct: +61 (7) 3166 7684
Fax: +61 (7) 3368 3754
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