In some Cisco equipment you may run into a common error when installing a 3rd party transceiver. 

Here is an example of what will be displayed:

%PHY-4-UNSUPPORTED_TRANSCEIVER: Unsupported transceiver found in Gi1/0/0

%GBIC_SECURITY_CRYPT-4-VN_DATA_CRC_ERROR: GBIC in port 65538 has bad crc 

Depending on the model you have the wording may be different, however the solution remains the same.

Simply input this command into the CLI: service unsupported-transceiver

This will cause this to be displayed on your screen:

Warning: When Cisco determines that a fault or defect can be traced to
the use of third-party transceivers installed by a customer or reseller,
then, at Cisco’s discretion, Cisco may withhold support under warranty or
a Cisco support program. In the course of providing support for a Cisco
networking product Cisco may require that the end user install Cisco
transceivers if Cisco determines that removing third-party parts will
assist Cisco in diagnosing the cause of a support issue.

This error is Cisco telling you they want you to buy their transceivers and will not troubleshoot or guarantee 3rd party transceivers. You must go through the manufacture of the transceiver for support if they malfunction.


Note: This is no way voids your warranty with Cisco.

Now enter the command: no errdisable detect cause gbic-invalid


This disables the auto port shutdown upon inserting a 3rd party transceiver. At this point your switch should happily accept your new compatible transceiver.


If for some reason your transceiver is still not working at this point please open a ticket with us here.