[c-nsp] 10gig Link Bouncing Consistently

Nick Hilliard nick at foobar.org
Thu Apr 4 09:38:41 EDT 2013


On 04/04/2013 00:03, Justin Krejci wrote:
> Unfortunately SR/MMF transceivers have no DOM support.

I'd better RMA my SR optics then.  They report DDM just fine, so there's
obviously something wrong with them :-)

> 3. Cable length is between 150 and 200 ft. OM2 should be good up to 150
> meters @10 gig-e. The fiber is also pretty new, perhaps 2 years old.

82m according to http://goo.gl/gf3nG, or 66m if you're using standard
50/125 MMF. The important figure is not the length but the link
attenuation, and the attenuation will be affected if you use patch cables.

Have you cleaned everything thoroughly with one-click cleaners and a swipe
cleaner?  You should get a light meter and measure the rx level at both
ends.  This will tell you whether you are within your optical budget.

Nick

> We'll definitely get some fiber power meter tests ran during "the problem" time @ 850nm
> 
> Physical inspection has been completed already as well. No obvious places where there would be any sort of environmental impact and no current signs of distress/damage to the fibers.
> 
> Fiber ends have been cleaned thoroughly.
> 
> ________________________________________
> From: cisco-nsp-bounces at puck.nether.net [cisco-nsp-bounces at puck.nether.net] on behalf of Michele Bergonzoni [bergonz at labs.it]
> Sent: Wednesday, April 03, 2013 2:29 AM
> To: cisco-nsp at puck.nether.net
> Subject: Re: [c-nsp] 10gig Link Bouncing Consistently
> 
>> Beginning several days ago both links began flapping every 5 and a half
>> hours, both links have this happen within a couple of minutes of each
>> other.
>> They will flap for several minutes and then return to normal operation
>> requiring no user action and the ports never enter err-disable or show
>> any other symptoms.
> 
> Your story popped me up a distant memory of a heating system that
> happened to leak steam on a fiber cable. That cable contained all the 4
> fibers of a presumed redundant connection.
> 
> I would not let the next predicted flapping time pass without:
> 
> * "show interface transc det" when everything works, and when things go bad
> * technicians at both ends ready to disconnect one line and test the
> loss on the fibers with appropriate instruments, in the first window
> (~850 nm)
> * physical inspection of the fiber run, if feasible
> 
> If the fibers turn out to be OK, when you have a Cisco 6509 on one end
> and a Netgear on the other, and you need to try to replace one of them,
> we all know where to start.
> 
> Regards,
>                                 Bergonz
> 
> 
> --
> Ing. Michele Bergonzoni - Laboratori Guglielmo Marconi S.p.a.
> Phone:+39-051-6781926 e-mail: bergonz at labs.it
> alt.advanced.networks.design.configure.operate
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
> 
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
> 



More information about the cisco-nsp mailing list