Clients can't connect after Switch change

[rhcsgcsc]

We have recently installed a new Cisco 3524 switch at a remote site which is connected to a Cisco 6509 over fiber. This setup will be replacing the current equipment of a Dell PowerConnect 3024 Switch back to a Cisco 2501 router which ties back to the same 6509. Both networks are seperate: Seperate equipment, seperate IP Schemes,etc.

When we try to move the clients from the Dell PowerConnect 3024 to the Cisco 3524, the clients can no longer connect to the network. However, any machine that has not been on that network segment previously (i.e. my laptop), has no problem connecting on the new segment.

Any thoughts?

[Georg Pauwen]

Hello,

the MAC addresses from the devices previously connected might still be retained in the ARP table of the 6509. Try and clear the arp table on the 6509:

Switch#clear arp (for IOS switches)

or

Switch clear cam (for CatOS switches)

Regards,

GP

[rhcsgcsc]

GP,

Thanks for taking the time to address this issue. Unfortunately, we have already cleared the ARP cache on the 6509. I could only imagine that the MAC Address is being stored somewhere and trying to route back to the old segment as well.

In order to test that, we moved all clients to the new switch, powered off the old switch, cleared the ARP cache on the 2501 and the 6509.

Still no luck!

[Georg Pauwen]

Hello,

have you tried to clear the arp cache on the clients with the 'arp -d' command ? Is there anything configured on the switchports of the 3524 like port security ?

Regards,

GP

[rhcsgcsc]

Yes, I have tried clearing the arp on the client. Here is what I have found:

If I log on to a client machine that is disconnected from the network, let windows desktop start, and then plug the network cable into the switch, I get a dhcp address and everything is fine.

However, If I tried to start the machine (running W2K) with the network cable attached to the switch, it will never finish booting. It hangs at "Preparing network connections" or "Applying computer settings".

Looks like some component of windows is causing network failure.

[burleyman]

Try setting the speed and duplex on both the switch side and the client side....see if that works. Also could you post a config.

Mike

[rhcsgcsc]

burleyman,

Have also tried to change duplex and speed settings both on the switch and the client. Think this is a driver issue. It has an integrated 3Com 3c920 (3c905-tx compatible). I am going to updgrade the drivers and make sure that the power management features are turned off.

[Georg Pauwen]

Hello,

you might want to check this document, it mentions compatibility issues between specific NICs and the Catalyst switches. I think the type of NIC you have is mentioned with having intermittent DHCP problems. The solution proposed is to upgrade to the latest driver...

Troubleshooting Cisco Catalyst Switches to NIC Compatibility Issues

http://www.cisco.com/warp/public/473/46.html#nic_comp

HTH,

Georg

[burleyman]

Does the modules that the clients connect to, supply power? What is the P/N of the modules? We had the same problem here that I just fixed. It turned out to be the modules we had in the switch supplied power for our upcomming VoIP deployment but we did not have anything in place. I needed to a set port inlinepower MOD/PORT off

That fixed our problem.

Mike

[rhcsgcsc]

Thanks to all who have replied.

I have spoken with 3com,Dell,and Cisco... none of which have provided me with an answer. Let me make clear that this is a 3524 XL, not a 3524 PWR-XL. No Inline power features in this switch.

I am convinced it is a Driver issue with this card specific to Windows 2000. My machine runs XP with the same integrated card and it works fine. Other machines with different NICs running Windows 2000 connect fine. 3com or Dell have yet to supply me with a work around.

[glen.grant]

Have made sure you have portfast on and trunking and channeling off for all the end user ports ????