Antonio, for whatever reason when we tried to reuse the same account, SSO was 
failing.  We ended up creating a new account, running the KTPass on that one 
and it worked.  TAC also immediately went to that resolution when we discussed 
with them.  Good luck... D.J.


D.J. Owens 
Senior Architect
The Cincinnati Insurance Companies
Office: (513) 870-2300 x4195
Fax: (513) 881-8900
 
CONFIDENTIAL COMMUNICATION:
This message is intended for the use of the addressee,
and may contain information that is protected by attorney-client privilege.
If you are not the intended recipient, any dissemination of this communication 
is strictly prohibited.
If you have received this communication in error, please erase all the copies 
of this message and its attachments and notify the sender immediately.

-----Original Message-----
From: Cisco Clean Access Users and Administrators 
[mailto:[email protected]] On Behalf Of Antonio Soares
Sent: Friday, November 12, 2010 8:55 AM
To: [email protected]
Subject: Re: NAC 4.8 SSO and WIN7

Hello Rob,

We decided to run the ktpass against the existent cas user instead of creating 
a new one. The ktpass syntax used was exactly as mentioned in the CAS 
configuration guide:

-------------------------
For Windows 2003 Server at full functional level: 

ktpass -princ newadsso/[adserver.][email protected] -mapuser newadsso -pass 
PasswordText -out c:\newadsso.keytab -ptype KRB5_NT_PRINCIPAL
-------------------------

Creating a new user is not mandatory for this to work I think. So it should 
work but it still fails for WIN7 users.

In the meanwhile, I asked the customer to see if they really have
RC4_HMAC_MD5 enabled. It seems this should be on by default on all WIN7
installations:

http://technet.microsoft.com/en-us/library/dd560670%28WS.10%29.aspx
 
But for example, my laptop doesn't show any algorithm enabled here:

Control Panel > Administrative Tools > Local Security Policy > Local Policies > 
Security Options > Network security: Configure encryption types allowed for 
Kerberos



Thanks.

Regards,

Antonio Soares, CCIE #18473 (R&S/SP)
[email protected]


-----Original Message-----
From: Cisco Clean Access Users and Administrators 
[mailto:[email protected]] On Behalf Of Rob Chee
Sent: sexta-feira, 12 de Novembro de 2010 11:27
To: [email protected]
Subject: Re: NAC 4.8 SSO and WIN7

Antonio,

I've set this up successfully for a client using NAC 4.8 and Windows 2003 
domain controllers.  They were running 4.8 and initially had the ktpass command 
with the +DesOnly at the end.  When they introduced Windows 7 machines into the 
network we found that AD SSO did not work for those computers.  At that time we 
followed the instructions in the guide you posted.  We created another AD user 
to assign to the AD SSO portion of the NAC server config.  The ktpass command 
used for this user did not have the
+DesOnly at the end.  We then changed the NAC Servers to use the new AD
user and everything worked correctly for both the Windows 7 and Windows XP 
computers.

I have a little blog on why the +DesOnly is not required.
http://www.netcraftsmen.net/resources/blogs/cisco-nac-ad-sso-support-for-no
n-des-encryption-types.html

Are you sure the users had a valid Kerberos ticket?  You can use kerbtray.exe 
on the end clients to verify that they weren't using cached credentials...

Are you using ACLs to restrict the authentication VLAN?  I've seen cases when 
one of the domain controllers was blocked by the authentication VLAN ACL, which 
caused problems similar to what you're seeing...

------------------------------------------------------
Rob Chee, CCIE #8188 (R&S and Security)
Senior Network Consultant
Chesapeake NetCraftsmen, LLC.
Company Website:  http://www.netcraftsmen.net My Blog:  
http://www.netcraftsmen.net/resources/blogs/blogger/Rob%20Chee/
Mobile:  571-437-2829
------------------------------------------------------




On 11/10/10 7:59 AM, "Antonio Soares" <[email protected]> wrote:

>I have a customer that is running 4.8. The upgrade to this release was 
>made a few days ago. After running the procedure to support the Windows 
>7 clients, we see that SSO is not working. We are using ktpass version
>5.2.3790.1830 and this is a Windows 2003 environment.
>
>The procedure is this one:
>
>http://www.cisco.com/en/US/docs/security/nac/appliance/configuration_gu
>ide
>/4
>8/cas/s_adsso.html#wp1277452
>
>The problem is that the users do the Windows authentication and the NAC 
>Agent window appears for login. SSO does not work for these users.
>
>Anyone has seen this problem before ?
>
>
>Thanks.
>
>Regards,
>
>Antonio Soares, CCIE #18473 (R&S/SP)
>[email protected]

Reply via email to