Issues doing 10-Gig connection from 3850 to 3750-x with C3KX-NM-10G Module

[zeke.shif]

Hi, this is my first post to a Cisco forum.

We have a 3750-X with the 10-G module, and want to connect it to our newly-purchased 3850.

I realize the SFP+ cable we are using may not be supported, but before I even tackle that issue, I am curious which physical interface is associated with which interface in the config.

On the C3KX-NM-10G module, I have a working regular SFP 1-Gig connection in port 1 (GigabitEthernet 1/1/1).  No issues with this.

However, I try to put the connection to our 3850 into port G4/TE2 on the 10G module, and it does not work.  I've done the "service unsupported-transceiver" and "no errdisable detect cause gbic-invalid" config commands...but I'm curious as to why the error I get is reported on "Gi1/1/4" ?

Jan  4 16:00:14.064: %GBIC_SECURITY_CRYPT-4-VN_DATA_CRC_ERROR: GBIC in port Gi1/1/4 has bad crc
Jan  4 16:00:14.064: %PHY-4-UNSUPPORTED_TRANSCEIVER: Unsupported transceiver found in Gi1/1/4

Is there something I need to do to make this 4th interface be TenGigabitEthernet 1/1/2  instead of GigaBitEthernet 1/1/4 ?  I've configured the interfaces the same, I'm just curious how to make G4/TE2 behave as a 10-gig interface.

interface GigabitEthernet1/1/4
 description Trunk to F2-1-5-3850-XS on TenGigabitEthernet 1/0/24
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 106,155,157,255,355,455
 switchport mode trunk
!
interface TenGigabitEthernet1/1/1
 description Trunk to F2-1-5-3850-XS on TenGigabitEthernet 1/0/24
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 106,155,157,255,355,455
 switchport mode trunk
!
interface TenGigabitEthernet1/1/2
 description Trunk to F2-1-5-3850-XS on TenGigabitEthernet 1/0/24
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 106,155,157,255,355,455
 switchport mode trunk

I should note that we hot-swapped the C3KX-NM-1G 1-gig module out for our new C3KX-NM-10G module  (not sure this makes a difference)

Hardware:  cisco WS-C3750X-48 with C3KX-NM-10, running version 12.2(55)SE5

Any help appreciated..

[Philip D'Ath]

You get the %GBIC_SECURITY_CRYPT-4-VN_DATA_CRC_ERROR error when you use non Cisco SFP+ kit.

[zeke.shif]

Correct, but why am I getting an error with regard to Gigabit Ethernet 1/1/4, and not TenGigabitEthernet 1/1/2  ?

The fourth interface on the C3KX-NM-10G module says "GE4/TE2", and in the config, there are both GigabitEthernet 1/1/4, as well as TenGigabitethernet 1/1/2"

In the config, I can do:

F2-1-2-Core-3750x-G#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
F2-1-2-Core-3750x-G(config)#int g1/1/4
F2-1-2-Core-3750x-G(config-if)#

as well as

F2-1-2-Core-3750x-G#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
F2-1-2-Core-3750x-G(config)#int te1/1/2
F2-1-2-Core-3750x-G(config-if)#

Which one of those is that 4th physical interface on the C3KX-NM-10G module?

If I were to obtain a Cisco SFP+ kit, would the switch automatically figure this out, and any config operations I did on Interface TenGigabitEthernet 1/1/2 would automatically apply to this phyisical interface?

[Philip D'Ath]

Refer to these installation notes for the module:

C3KX-NM-10G

Note these specific notes:

The module has four slots. Two slots support only 1-Gigabit SFP modules.

Two slots support either 1-Gigabit SFP or 10-Gigabit SFP+ modules.

Note The GLC-T SFP is not supported on the SFP+ slots of C3KX-NM-10G.

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.

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

A 10-Gigabit SFP+ module takes precedence over a 1-Gigabit SFP module except when an SFP module is first inserted in Slot 1 and has link. When you insert an SFP+ module in Slot 2, the SFP in Slot 1 retains link. The SFP+ module in Slot 2 does not operate.

When the SFP module in Slot 1 is shutdown, loses link, or is removed, the SFP+ module in Slot 2 turns on. The SFP module in Slot 1 does not work as long as an SFP+ module is in Slot 2, whether it has link up or not.

The same precedence applies to Slots 3 and 4

[Philip D'Ath]

I also don't like your chances using what you know to be the wrong modules plugged into the switch.