1G SFP in a Catalyst 3850 uplink module reported unsupported and err-disabled
6
The poster has a stack of two Cisco Catalyst 3850-48T switches, each fitted with a 2x1G/2x10G fiber uplink network module. Two 10G fiber links already run in slots 2/1/3 and 2/1/4. When a single-mode 1G SFP is inserted into 1G slot 2/1/1, the switch reports the module as unsupported and places the port in err-disabled state. The poster asked whether the 1G slots become unusable once the 10G slots are populated, or whether something else is wrong. No module part number, IOS version or exact log line was provided, and the thread ends without a confirmed fix.
- Hardware: Cisco Catalyst 3850-48T (WS-C3850-48T) stack, Cisco C3850-NM-2-10G (2x1G + 2x10G) uplink module
- Transceivers: 1G single-mode SFP (unspecified), 10G SFP+ (unspecified)
- Form factor: SFP, SFP+
Symptoms / messages:
module unsupported
port err-disabled
1G SFP not accepted in uplink module slot 2/1/1
Comments 4
Identify the exact network module with 'show module' or 'show inventory' and review Cisco's document on unsupported GBIC/SFP modules in sub-modules (document 200296).
Verify the optic against the Cisco transceiver compatibility matrix at tmgmatrix.cisco.com.
The combination should normally work; if the SFP is not on the supported list, try 'service unsupported-transceiver'.
A respondent asked which firmware the stack is running; the poster never replied.