[c-nsp] Simultaneous drops - 2 upstream providers

[Antoine Monnier]

I thought fibre optic cable were immune from electrical interference.

What about Spanning-Tree ? Is your 3750X talking STP with any of the third
party equipment?


On Tue, Aug 20, 2013 at 7:16 AM, CiscoNSP List <cisconsp_list at hotmail.com>wrote:

> Not that I am aware of, and not that they have advised (I have asked)
>
> fibre x-connect to carrier A from our rack, ME3400 in our rack for carrier
> B to x-connect back to there rack
>
> Can electrical interference cause something like this on the x-connects?
> (And not present as drops/errors on the ports?)
>
> Going to try an alternate port on the 3750 tonight for carrier A
>
>
> Date: Tue, 20 Aug 2013 07:03:45 +0200
> Subject: Re: [c-nsp] Simultaneous drops - 2 upstream providers
> From: mattias at gyllenvarg.se
> To: cisconsp_list at hotmail.com
> CC: ikiris at gmail.com; cisco-nsp at puck.nether.net
>
> A and B uses A or Bs infrastructure at eighter end of the link? Or a
> common third party somewhere in the signal path.
> Den 20 aug 2013 05:23 skrev "CiscoNSP List" <cisconsp_list at hotmail.com>:
>
> Thanks Blake -
>
>
>
> Both links (that drop) are doing minimal traffic (One is only a backup
> link, so isnt used) - the link that is not affected is doing
> ~100-150Mb/sec, Carrier A link is doing 5-10Mb/sec and Carrier B virtually
> zero(As it's a backup link as mentioned)....seeing minimal output drops on
> each port
>
>
>
>
> All links are Gb (physical), and carrier rate limits (Carrier A 50M,
> Carrier B 200M and carrier C 1Gb)
>
>
>
>
>
>
>
> From: ikiris at gmail.com
>
> Date: Mon, 19 Aug 2013 21:51:10 -0500
>
> Subject: Re: [c-nsp] Simultaneous drops - 2 upstream providers
>
> To: cisconsp_list at hotmail.com
>
> CC: cisco-nsp at puck.nether.net
>
>
>
> You don't give too much information here, so its hard to speculate.
>
>
>
> My guess as to the first thing to check would be out of buffer drops on
> the 37x, but like I said above, it's only really a wild guess, since you
> don't specify port layout or link speeds. You can verify by looking at the
> ASIC stats, as the interface stats can be unreliable for that type of drop.
>
>
>
>
>
>
>
>
> -Blake
>
>
>
>
>
> On Mon, Aug 19, 2013 at 9:11 PM, CiscoNSP List <cisconsp_list at hotmail.com>
> wrote:
>
>
>
>
>
> Hi - bit of a strange one - We have 3 interpop links (3 different
> carriers) terminating on a 3750X+ASR at one of our POPs, and are seeing
> intermittent drops on 2 of the links(And ospf loses adjancency) at the same
> time
>
>
>
>
>
>
>
>
> Carrier A - POPA -> POPB - We see drops/ospf adjancency issues once/twice
> a dayCarrier B - POPA -> POPC - We see drops/ospf adjancency issues
> once/twice a dayCarrier C - POPA -> POPB - No issues at all
>
>
>
> All links terminate on the same 3750, and then are trunked to an ASR1006
> for L3 - There are no errors/physical link issues on the 3750, and both
> carriers also do not see any errors/link drops.
>
>
>
> It would be improbable that both carriers have issues on there networks at
> precisely the same time, so it is either our switch(3750), or something
> weird happening with the x-connects that doesnt cause the links to drop,
> doesnt cause any errors etc, but causes ospf to lose adjacency (but only
> for 2 providers, not the third?)
>
>
>
>
>
>
>
>
> Any suggestions/assistance is greatly appreciated
>
>
>
>
>
>
>
> _______________________________________________
>
>
>
> 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/
>
>
> _______________________________________________
> 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/
>