Vaild serial number for GLC-SX-MM..thnx for help!

Unanswered Question
Giuseppe Larosa Sat, 11/14/2009 - 12:00

Hello Ted,

may you explain what is your problem?

the GLC has troubles or are you evaluating it to buy?

I may be wrong but there is no tool that given a serial number can tell you if the product is original or not.

Hope to help


Richard Bradfield Sun, 11/15/2009 - 16:32

I have a number of SFPs starting with s/n "FNS" I beleive I bought Cisco SFPs.

Note I tried to plug in an HP SFP and it was rejected by the switch



Leo Laohoo Sun, 11/15/2009 - 17:59


Cisco's SFP has an EEPROM algorithm that gets interrogated by the appliance. If the response doesn't match, the appliance will "err-disable" the port.

You have to either use Cisco SFP modules to get this to work or google for the other method.

Hope this helps.

The problem is there are knockoffs that have that have cloned the program in the eeprom so that CISCO gear recognizes it as valid, but CISCO has gone to setting up a database of valid serial numbers. They have an internal database but if you have a CISCO maintenance contract you can plug the serial number in and it will come back EITHER A) that the prodcut is not valid for coverage(due to the fact that it is covered by the switch) or B) that the serail number is invalid which means its not in CISCO's internal database and the odds are it is a knockoff. The one caveat is that there are reports of serial numbers not getting transmitted or added to the database. In any event if it comes back invalid the odds are it is genuine CISCO.

Leo Laohoo Sun, 11/15/2009 - 19:36

So are you saying that Cisco has loaded every router with the valid s/n? This doesn't make sense.


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