Cisco SG300 Port Authentication 802.1x no Logon Servers Available

[dominique.guyer]

Hi,

I have configured a Microsoft Server 2008 R2 with Radius Server and connect it with a Cisco SG300 Switch.

If a new device connect to the switch it goes automatically to the guestnet. If a device with the correct certificate and a valid useraccount connect to the switch, the deivce goes in to the local company network.

Now my problem:

If I connect a device which is in the domain and which have installed the correct certificate and want to login with a new domain user (which is not cached in windows) I can not login.

The following message appears: "There are Currently no Logon Servers Available"

I think the problem is that the authentication process only starts after a user have succsess logged in in windows.

Now I search for a solution which allows me to conntact the Logon Server for Domain Login before the User has logged in.

I hope someone can help me by this problem.

Thanks for every input!

Regards,

Dominique

[jurodri3]

Hello Mr. Guyer,

Please try the following steps, I hope it helps you.

1. Check the      DNS settings on both servers and clients, and correct any
   errors.

2. It is      better to load on protocol, TCP/IP only.

3. If you      have mixed network
   , setup WINS server or install NetBIOS      over
   TCP/IP on W2K/XP instead of loading NetBEUI.

4. Also make      sure that Domain Controllers register their DOMAIN<1C>      NetBIOS
   names with the WINS Server.
   

5. The fix is      to use hybrid node instead of p-node or m-node.
   

6. If the      network is configured to use for NetBIOS name resolution but      the
   client hasn't been set manually, it could be set through a      DHCP release
   option 46.

7. Apply      service pack.

8. Also check      the time on both client and server (should be the same).

9. If the      problem is still occurring, you need to start checking the DC and      Active Directory (for example, check that the relevant Computer      objects are in the right Active Directory sites to ensure they are      trying to contact the appropriate domain controllers).

I hope you find this answer useful, if it was satisfactory for you, please mark the question as Answered.

Diego Rodriguez

Cisco network engineer

Thank you