SC / LC connector gives CRC at SC end.

[leninstcs]

HI ,

I have a PIX 535 connected through OFC to Cisco 2960 Switch.

PIX end - G0 (SC type Connector) - Switch End - Gi1/0/28 (LC type connector)

When I am pinging from either side, I am getting packet drops.  CRC error is increasing at PIX interface.

Speed settings, tried with

auto - auto

auto - nonegotiate

nonegotiate - auto

nonegotiate - nonegotiate

But no improvements. 

When its connected with SC - SC connector, its working fine.

Switch also working fine when connected LC - LC.

Switch OS is 15.x  version.

Cisco PIX Security Appliance Software Version 7.0(4) <system>

Device Manager Version 5.0(4) Cisco PIX Security Appliance Software Version 7.0(4) <system>
Device Manager Version 5.0(4)

What could be the problem, and is there any work around available?

[chris-hart]

I know nothing about PIX Firewalls but the type of connector should not be causing CRC errors.  As you say that the CRC errors are only occuring at the PIX when you use the LC connector then I would check to make sure you have the same type of SFPs at both ends and also that the fibre patch leads are the same type.I would check to make sure that the optical cables are the correct type for the interface ie use Multimode Fibres to connect to SX GBICs/SFPs and Singlemode Fibres for LX GBICs/SFPs.

Another thing worth checking is that the optical power that is being received is correct, if its to high or low that could cause errors, I would also check to make sure that the optical face is not dirty or damaged, try replacing the fibre with a spare, it is also possible that you have a faulty SFP so try swapping that out for a known good one as well.

I'm not sure if you can do this but swap the fibre round by moving the TX to the RX at both ends, do the CRC errors move?

Also check that the speed and duplex settings are the same at both ends.