3750X issue with the 10G NM

mikearama

We have a few 5-switch stacks of 3750X's. Each stack has a pair of NM's... C3KX-NM-10G's, which provide 4 ports, the descriptions of which are G1, G2/TE1, G3, and G4/TE2. So far, I'm only using the TE's as uplinks. One NM is in switch-1 (T1/1/2), the other in switch-5 (T5/1/2). The 10Gb uplinks connect back to a pair of 6506's.

I now need to connect another switch (3750-TS) to one of the stacks. It's a fair distance away, so fiber is required. So, I put a 1gb sfp into G1 in switch-1, expecting that, since the only other thing in the NM is the 10Gb uplink is G4/TE2, this should work fine. However, the 1Gb port came up, while the 10Gb port went down.

I can find nothing to support why this happened. Am I to assume that I get either four 1Gb ports? OR two 10Gb ports? but not a mix? Preciate any links.

Thanks,
Mike

chmorin

mikearama wrote: »

I can find nothing to support why this happened. Am I to assume that I get either four 1Gb ports? OR two 10Gb ports? but not a mix? Preciate any links.

Thanks,
Mike

This is the only thing I can find: http://www.cisco.com/web/DK/assets/docs/presentations/Cisco_Tech_Update_Oktober10.pdf - do a search for "C3KX-NM-10G"

I'll quote:

Network Module

Provides flexibility with two options:
• Four 1G ports (SFP)
• Two 10Gig port (SFP+) or four 1G ports (SFP)

I bolded the bit that seemed important. It seems that the C3KX-NM-10G has two SFP and two SFP+ modules. Looking over it I don't see this to being any help to you... but hopefully it helps get you on the right track. I'm not experienced enough with this stuff. Maybe now that you have two links you need to force them to their speeds?

IDK, but thought I would try. Sorry.

mikearama

Not conclusive... but you're right, a pretty clear indication:

2 10Gb ports OR 4 1Gb ports. No mixing listed. Dayum.

*BB*

Here is the document for the modules. It tells you the combinations as to which SFP ports can be used.

Installation Notes for the Catalyst 3750-X and 3560-X Network Modules - Cisco Systems

Im still waiting for my SFP+'s to come in...

mikearama

*BB* wrote: »

Here is the document for the modules. It tells you the combinations as to which SFP ports can be used.

Good find, bro... I bookmarked it. It also, however, doesn't comment on mixing 1 and 10Gb sfp's in the same NM. Nor does the Compatibility Matrix link at the bottom of the page... that only says which version of switch can take which version of module.

I guess I'll have to order in a 1Gb NM and plan an outage to move it to another switch in the stack.

chmorin

mikearama wrote: »

Good find, bro... I bookmarked it. It also, however, doesn't comment on mixing 1 and 10Gb sfp's in the same NM. Nor does the Compatibility Matrix link at the bottom of the page... that only says which version of switch can take which version of module.

I guess I'll have to order in a 1Gb NM and plan an outage to move it to another switch in the stack.

His resources actually does comment on mixing 1 and 10Gb SFP's:

The four slots are grouped as two pairs, with each pair consisting of one SFP slot and one SFP+ slot. Each pair supports either two 1-Gigabit SFP modules or one 10-Gigabit SFP+ module. A 10-Gigabit SFP+ module cannot operate at the same time as the corresponding 1-Gigabit SFP module in the pair.

That probably explains your problem, but I can't see your physical termination regarding the pairs.

*BB*

mikearama wrote: »

Good find, bro... I bookmarked it. It also, however, doesn't comment on mixing 1 and 10Gb sfp's in the same NM. Nor does the Compatibility Matrix link at the bottom of the page... that only says which version of switch can take which version of module.

I guess I'll have to order in a 1Gb NM and plan an outage to move it to another switch in the stack.

You shouldnt need to order another NM, the comments about mixing is near the top of the document:

Supported combinations of SFP and SFP+ modules:
•Slots 1, 2, 3, and 4 with 1-Gigabit SFP modules
•Slots 1 and 2 with 1-Gigabit SFP modules and Slot 4 with one 10-Gigabit SFP+ module
•Slot 2 with one 10-Gigabit SFP+ module and Slots 3 and 4 with 1-Gigabit SFP modules
•Slot 2 and Slot 4 each with 10-Gigabit SFP+ modules

mikearama

Fantastic. That's what I was looking for. Don't know how I missed it in the doc.

Thanks gents. BB... that link just went from being a "good" find to a "great" find.