Dell 1850 Mac Address problem

[Fatbloke38]

Hi,

We have a rack of Dell servers, 1750',2850's and some new 1850 Poweredge servers.
All are fine except the new 1850's, here is the problem.

The 1850's for some odd reason keep showing thier Mac Address as the same as the Pix 515 Firewall we have on the network. After a boot all is fine until you try and ping the server, one reply and then nothing. arp -a shows the server as having the Firewall Mac Address.

We do not think the Firewall is causing the problem as the other servers are fine. Although when we remove the Firewall from the equation it does not happen. Dell of course have no knowledge of any such problems.

Please advise

Glenn

 

[LawnBoy]

Is the MAC on the 1850s actually changing?

 

[Fatbloke38]

The client pinging the server has the arp incorrect. The actual Mac Address of the server does not change.

Glenn

 

[LawnBoy]

Is the client on the other side of the firewall? Do you have proxy running on that firewall? If yes to both, this is expected behavior.

 

[Fatbloke38]

No, same side of the firewall.

 

[LawnBoy]

That's quite bizarre. I don't think I've seen anything like that before, sorry. Assuming the netmask(s) are correct, the firewall shouldn't even be involved.

When you figure this out, please update this thread with what you find. There is a PIX forum here at Tek-Tips, maybe they can help.

 

[NickFerrar]

Are they on the same subnet, I'd assume so if ARP is showing you anything meaningful. If they are on different subnets are you sure routing isn't going via the firewall (which would give a false MAC to an ARP request)

 

[Fatbloke38]

We have disabled the onboard NICS on the server and are using a USB network adapter, all is fine now. Will get back onto Dell and let them know the situation. Seems like hardware based issue.

I will keep this thread going until it is resolved.

Thanks for input on this.

Glenn

 

[jkupski]

If the machine you're pinging from has the PIX's MAC address in its ARP cache, it's pretty hard to blame the 1850s.

What happens when you put a sniffer on the network? Where's the ARP traffic coming from?

 

[Fatbloke38]

It's looking more like a NIC problem at the moment.