1st here's the switch type that I'm demo'ing this on.
Next, we will install a inferior SFP optical transceiver; 1gig SFP MM . And you will notice the port will go into err-disabled and cisco will log this;
Okay let's stop here and see why we get this. Per cisco, they don't like or allow anybody else SFP/SFP+. Here's the quote from cisco website on how the checks works;
Basically they have a eprom that contains a crc code and serial information and when cisco runs the check, they fail and the SFP is marked incompatible.
Here's a list of SFP that are supported.
Now I know of one vendor that seems to make vendor neutral optics.
So if you have to use a 3rd party optics or don't want to buy cisco new prices, look at transition and call them up. btw: I used to work for one of their sister company. Transition networks has always been an alternatiev optic vendor. I have not used any of their SFP+ optics, but their 1gig stuff is solid.
Okay so now when we install the correct SFP into a cisco switch, it 's now happy and dorky and ready to go.
I 've worked on numerous projects and deals, where the cost of the optics and any conversion , became the deal breaker.
Xenpak to Xenpak2 to SFP+
GBIC to SFP
Almost all new network gear are moving to the Small Form Pluggable format. And it's a big forklift ( $$$$.$$ ) from path-cables and optics to refresh your network or DataCenter from one type to another. In one client that did a refresh, they spent over 30K in patch cables alone, with moving from the SC-SC to LC-SC interfaces cables, & across 30 sites and on two continents.
btw: I can help and consult on matters related to this example.
Cisco and most other vendors , does; " the buy my optics & only my optics", only due to any of the below factors;
- to ensure you buy a quality transceiver
- to eliminate any tac support case due to hardware issues related to a 3rd party
- to make money with the customer, & buying the cisco branded product
- to eliminate any knock offs or fakes
Now you will be surprised to find , that the SFPs in use today, are made normally by a handful of vendor and they make these across the board for all network/server suppliers.
In fact, they make one round for vendor X and then another round for vendor Y and so on. And if I had to guess, it comes from the same chinese shop.
Now with all of the above said, I want to show you some interesting things pertaining to SFP transceivers and 3rd parties. The unknown SFP from the above example, actually works in a cisco 3835.
Yes the cisco 3560 switch, rejected the same SFP , but the router was okay with it. Here's a "show controller gi 0/0" output for that transceiver;
Notice the FINISAR corp? And part# FTFL8519P2BNL?
Okay guess what, the cisco brand GLC-SX-MM are also manufactor by the same vender ; FINISAR.
So the same vendor with a cisco brand vrs non-cisco brand. And the non-branded SFP does not, and let me repeat, " does NOT work in a cisco switch " but works in a router.
Okay you think that's weird, a cisco brand GLC-SFP-T 1000baseT SFP adapter of mine that works in a cisco switch. Does not work in a cisco router. I have numerous cisco TAC case on this exact issues, and TAC has been mute and speechless with giving me an solid answer; "as to why?". They have always exchanged or replaced the SFP transceiver, but you would expect a cisco branded SFP, would work in a cisco router or switch.
Look here if you doubt me;
Yes, this was from a cisco brand GLC-T, & that did not work in a cisco router.
Here's the line up of the 4 SFP that I tested for this blog, one being a 1000baseT and 3 being a GLC-SX-MM fiber. With the top SFP being a cisco badge SFP, you can make it out if you look very close. The only un-labeled cisco SFP works in a router, but not in a switch.
And lastly, here's a another cisoc SFP that works in a router or switch;
So always remember to check for cisco compatible SFP, & if you don't buy cisco branded SFPs. And even a branded cisco SFP , might not work across all cisco hardware and linecards and ios versions.
btw: these last examples where done against a cisco 3825 running ioscode;
Freelance Network & Security Engineer
kfelix -at- hyperfeed --dot-- com