Unlocking CISCO devices to work with “unsupported” SFP
by tnk on Sep.21, 2008, under Cisco, Huawei, Networking
In cisco equipment there is one very irritating problem – it works only with “cisco” SFPs.
Well actually cisco is not manufacturing sfps so basically there is just some check going on inside the router/switch. It can drive you crazy if your only cisco sfp dies and you have nothing except for some normal 3rd party sfp (which is by cisco standard not compatible).
Well there is a way how to go around this. In ios command line write the following :
service unsupported-transceiver
This will cause this to come up 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.if that did not scared you off just continuewith the following:
no errdisable detect cause gbic-invalid
There are some cases that the sfp is not working properly but the odds are something like 100:1
As a side note Huawei equipment does not block any vendor’s sfp but has also list of supported modules which is rather to good idea to read because the “non-supported” sfps have usually some issues.
11 Comments for this entry
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March 8th, 2010 on 06:59
There is nothing clearly mentioned of how to unlock cisco device, the information you have provided seem to be not enough, can you expand your explanation.
March 8th, 2010 on 17:24
Hi the software unlock is done by those two commands mentioned above, the problem though is that the SFP does not have to be compatible i.e.: it will not properly register with the device or it will register but will not work anyway (I saw both variants multiple times with multiple SFPs).
Generally Cisco has this software lock for multiple good reasons
A) to avoid End users to complain about their no-name SFPs that are not manufactured to the desired standards
B) to avoid testing hundreds of SFP vendors and then solving the issues (usually because the vendor is just not able to follow proper specs)
C) to earn more money for their overpriced re-branded SFPs
So there are only two good options here
– either buy Cisco’s SFPs that will work always
– or try some decent brand which should work as well but is obviously not supported (I know that Agilent and Optech should work just fine).
If you decide otherwise and go for some cheap no-name brand you should be expecting some troubles…
April 4th, 2010 on 20:58
How to add this to my RSS reader? I’m sorry I am a novice :(
April 5th, 2010 on 18:33
There are three ways:
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or
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June 8th, 2011 on 10:45
Hi,
I would like to know if the two commands will unlook the C3750 to support GLC-FE-100FX? can you help on this issue: I have C3750V2-24TS-S and GLC-FE-100FX that in unkown by the Switch.
Thank you in advanced
BR
June 8th, 2011 on 11:22
In short these commands will make no difference to your current state.
In long – the port seems to be 1Gbps only (according to the manual on cisco web) so 100mbps SFP will not work as it is physically different on L1. These commands are just for disabling a CRC check of the SFP so it allows SFPs of vendors that are not certified by cisco (i.e. coretek/finisar) but the SFP you are mentioning is either cisco or prolabs who both have the crc in place so it should work straight away.
So check if the port is capable of 100mbps first and if it is (which I doubt) you have a faulty sfp.
June 8th, 2011 on 18:15
The port support 100 Mbps with the GLC-GE-100FX but I have GLC-FE-100FX that is not supported on C3750.
Can you help me with this issue. we tested with two Switches and two SFP modules and we have the same error message:
%PM-4-ERR_DISABLE: gbic-invalid error detected on Gi1/0/1, putting Gi1/0/1 in err-disable state
%LINK-5-CHANGED: Interface Vlan1, changed state to adminis tratively down
Thank you in advance
BR
June 8th, 2011 on 23:24
You can use those commands from the article as they are harmless no matter what the message says (and you can always remove them later from the configuration if you want). The only thing they do is that they disable the automatic check of the SFP and subsequent move of the port into err-disabled state. So if you say that the port does support the speed then it should be no problem. I am just wondering – are you using cisco (certified) SFP or some other vendor’s ? As if you use certified SFP I wouldn’t expect this sort of behavior…
June 9th, 2011 on 09:13
Thank you for your response, I confirm we use the Cisco modules and I have used the commands of your articles and i do not receive the message error that I have mentionned but the port is always down, it does not recognize the module.
BR
June 9th, 2011 on 10:48
I though that would be the case as you should never need those commands for the cisco’s own SFPs – the problem will be more likely that the switch just cannot support this type of modules in HW/IOS (or that the SFPs are faulty which i think is quite unlikely) anyway the supported types should be listed somewhere in documentation for the 3750 switch.
Sorry i couldn’t help you any more than this…
BR
July 7th, 2011 on 21:40
Thanks!