Conflicting MAC Address on two printers?!?!?

Hello everyone... how is your Tuesday treating you? I work for a school in Houston, Texas. We have several networked printers on our campus, but we are having problems with two in particular. We have an HP 4100N and HP 4200 that have conflicting MAC addresses. Is this possible? How can this be resolved?

--Thanks for your help,
Scooter

Quote:

---

Originally Posted by Scooter

Hello everyone... how is your Tuesday treating you? I work for a school in Houston, Texas. We have several networked printers on our campus, but we are having problems with two in particular. We have an HP 4100N and HP 4200 that have conflicting MAC addresses. Is this possible? How can this be resolved?

--Thanks for your help,
Scooter

---

In theory that is impossible. Each network card ever made is supposed to have a unique harware address, the MAC. I am assuming that the printers were purchased with the NIC's installed so that should not happen. That's kinda got me really baffled. Best I can say is call HP support.

By default, HP printers have the same IP address, but MACs should never reapeat under normal circumstances.

With DHCP enabled, both printers should be receiving their own IPs.

Have these printers ever worked together on the same network?

If they have it may not have been the MAC That is causing the problem.

I am assuming that the printers have HP Jet direct cards installed.

Most of these cards have the MAC affixed to a label on the card. Verify that they are unique.

You can also view the arp table with one of the Printers disconnected. Then compare the Arp table with the other connected.

well i work for a large cable isp that will go unnamed, and we see duplicate modems fairly regularly. guess some companies are just sloppy or lazy when it comes to keeping track of what macs they've used.

Quote:

---

Originally Posted by Joker1

well i work for a large cable isp that will go unnamed, and we see duplicate modems fairly regularly. guess some companies are just sloppy or lazy when it comes to keeping track of what macs they've used.

---

There was one model motherboard with onboard NIC that had the same MAC on EVERY SINGLE BOARD that came off of the line. They had to come out with a BIOS update so that they could be unique again, I don’t remember any of the specifics, I just remember seeing the talk here on the board after a couple of guys got several computers on their network and found the problem.

So, although not particularly likely that you’d end up with the same MAC on the same network, it is entirely possible to say the least.

Scooter, where are you? Did you check to see if the hardware addresses are actually identical? If so, contact the vendor, or HP directly. HP would probably send you out a replacement NIC if it was a fault in manufacturing…

Quote:

---

Originally Posted by Ya_know

There was one model motherboard with onboard NIC that had the same MAC on EVERY SINGLE BOARD that came off of the line. They had to come out with a BIOS update so that they could be unique again, I don’t remember any of the specifics, I just remember seeing the talk here on the board after a couple of guys got several computers on their network and found the problem.

---

MSI had a problem like that with some P4 boards.

Had two 3-Com cards once with the same MAC, so its entirely possible. I'd contact HP and get them to send a new JetDirect card out for one of the printers.