We have 2*c3850-48p in stack
ver 03.02.03.SE
We use 8 SFP as one trunk.
Suddenly 4 sfp became unknown, but link was active.
Gi2/1/1 connected trunk a-full a-1000 unknown
Gi2/1/2 connected trunk a-full a-1000 unknown
Gi2/1/3 connected trunk a-full a-1000 unknown
Gi2/1/4 connected trunk a-full a-1000 unknown
As soon as interface was still up and connected - packets were still redirected to this links, but packets were dropped.
So some users lost connection to some services connected to this stack. (4 links out of 8 were still active)
I have disabled these ports and reinserted SFP's, but that helped only for 3 of 4 links.
Gi2/1/1 disabled trunk auto 1000 1000BaseLX SFP
Gi2/1/2 disabled trunk auto auto unknown
Gi2/1/3 connected trunk full 1000 1000BaseLX SFP
Gi2/1/4 connected trunk full 1000 1000BaseLX SFP
After that i have replaced SFP's to NEW, but links are still same.
SFP's can be seen via show int trans det
Optical Optical
Temperature Voltage Tx Power Rx Power
Port (Celsius) (Volts) (dBm) (dBm)
--------- ----------- ------- -------- --------
Gi1/1/1 35.2 3.30 -7.3 -6.6
Gi1/1/2 34.0 3.30 -7.2 -6.2
Gi1/1/4 47.1 3.27 -7.4 -4.8
Gi2/1/1 44.6 3.27 N/A -6.9
Gi2/1/2 46.1 3.26 N/A -7.4
Gi2/1/3 45.5 3.27 N/A -7.4
Gi2/1/4 44.5 3.26 N/A -6.4
Switch is broken or what else?
