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Linksys GBIC in a Cisco 3560

I work in a medium size facility that uses CISCO switches. I recently received 2 Linksys MGBSX1s to evaluate. Normally SFP GBICs are a commodity item. We use several vendors with no problem. When I plug the Linksys GBIC in I get these messages:

%LINK-5-CHANGED: Interface GigabitEthernet0/1, changed state to administratively down

%GBIC_SECURITY_CRYPT-4-VN_DATA_CRC_ERROR: GBIC in port 65537 has bad crc

%PM-4-ERR_DISABLE: gbic-invalid error detected on Gi0/1, putting Gi0/1 in err-disable state

%LINK-3-UPDOWN: Interface GigabitEthernet0/1, changed state to down.

Checking the the Cisco Site I find this info for the CRC message:

%GBIC_SECURITY_CRYPT-4-VN_DATA_CRC_ERROR : GBIC in port [dec] has bad crc

Explanation The GBIC was identified as a Cisco GBIC, but it does not have a valid CRC in the EEPROM data.

Recommended Action Check to see if the Cisco IOS software running on the system supports the GBIC. If the GBIC is newer, a system software upgrade might be required. Even if the GBIC is unrecognized by the system, the GBIC may still operate properly but might have limited functionality.

I have updated my test switch to the most current level of IOS with no help.


Re: Linksys GBIC in a Cisco 3560

These errors usually mean the SFPs are not recognized or supported. Cisco-approved Small Form-factor Pluggable (SFP) modules have a serial EEPROM that contains the module serial number, the vendor name and ID, a unique security code, and CRC. When an SFP module is inserted in the switch, the switch software reads the EEPROM to verify the serial number, vendor name and vendor ID, and recompute the security code and CRC. If the serial number, the vendor name or vendor ID, the security code, or CRC is invalid, the software generates the security error message and possibly places the interface in an error-disabled state.

New Member

Re: Linksys GBIC in a Cisco 3560

It turns out that there is a setting to ignore the GBIC error. However, my boss is uncomfortable with that solution, so we returned the Linksys GBICs and purchased Cisco labeled GBICs.

Re: Linksys GBIC in a Cisco 3560

Hi Jim

Can you try using this command ?

service unsupported-transceiver


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