[c-nsp] Will UDLD work with converters ?

[Nick Hilliard]

On 02/10/2009 14:36, Jeff Fitzwater wrote:
> Is there any issues with running UDLD with TX to Fiber converters at
> each end of a gig cisco to cisco link? We are just over the distance
> budget with the 10KM optics.
>
> 6500 TX port--- to fiber converter--- 18KM fiber--- to converter--- back
> to TX port on 3750.
>
> We are looking at the converters because the Cisco ZX optics are very
> expensive and the converters with 30KM optics are much cheaper than the
> 60 KM ZX optics.

UDLD should be fine - it's just data packets, after all.  So unless your 
media converters are doing something very strange and very wrong, it will 
be fine.

You may want to look at third party optics from reputable manufacturers 
(e.g. http://www.finisar.com/optical_modules_2), although many 
organisations have policies in place which work against using third party 
components.  Also, it is very easy to pick up grey optics with cisco serial 
numbers on them, which means that the special command which we all know 
about isn't necessary.

Also, bear in mind that not all c65k ports support reading DDM info from 
SFPs.  SUP720 cards will, as will later hardware revisions of the 6724sfp 
blades.  Earlier hardware revisions won't.  Also, 12.2SX >= SXF9 will not 
present DDM unless it sees a Cisco serial number.

Nick