Cisco 3750 to Nortel Baystack 470-48T

Wow, Nortel still makes stuff? I thought they faded away long ago..

Going to their site, finding these switches, "Port 47 and Port 48 can be configured as either 10/100BASE-TX or make use of the built-in GBIC".

That to me says right away that you will get only 100-Base-FX with the GBIC out of this switch. You can't mix-and-match 1000-Base-SX and 100-Base-FX on any vendor, only copper ports are auto-sensing, auto-speed.

So this is an incompatible setup, one side is talking only Gigabit, the other is talking 100Mbit and they'll never talk to each other.

Cisco does now make a 100-Base-FX SFP for their switch line. Not very common, but it does exist. You can try downgrading the Gigabit on your

3750 to 100-Base-FX to talk to this switch, but obivously you won't get gig speeds. Or upgrade the switch on the otherside to be gigabit so it can do 1000-Base-SX (which I'm assuming is what you have in the 3750).

Thank you for your reply, Doug. Your information is really really helpful to me.

Regards

I have a look at the Nortel web site, it said$B!'(B

"Nortel Ethernet Switch 470 models are stackable switches providing resiliency, convergence readiness, and security and include two built- in GBIC (Gigabit Interface Converter) uplink ports"

"The Ethernet Switch 470-48T allows configuration flexibility: Port 47 and Port 48 can be configured as either 10/100BASE-TX or make use of the built-in GBIC. "

I think that means I can use port 47 and 48 as Gigabit ports by using the GBIC. I tried it, if I use the GBIC port 47 and 48, the copper port of 47 and 48 will be disable. And I did go to the Nortel Baystack

470-48T port config to see its port speed, it is 1000M.

Regards

This is common on several mid-range switches, either use the last two copper gigabit ports or the two built in SFP ports.

Now to your problem,

This most likely is some type of negotiation issue. On the 3750, configure the interface that connects to the Bay switch with the command:

switchport trunk nonegotiate

Make sure all your other port trunk settings match:

switchport trunk encap dot1q switchport mode trunk

Scott

snipped-for-privacy@xianli.net wrote:

We have fixed the problem and you are right, it is the negotiation problem. Thank you anyway:)

Regards