[c-nsp] Spanning-Tree vs. EoMPLS links in SXI2?

[Ben Basler (bbasler)]

Gert,

As you might know - Cat6500 is an ingress forwarding model - so the
forwarding engine on the ingress linecard does the work. If there is no
local FWD engine, the PFC on the sup does the work. In case of 67xx
modules a CFC relays the header to the PFC.

Having said that, there are some subtle differences how L2 PDUs (read:
LACP, STP, VTP, CDP, 802.1x, etc.) are handled by the 3B/3BXL and
3C/3CXL.

All in all - best case here to contact TAC and point them to the bug id
I mentioned - they should be able to verify if you are indeed hitting
this or something else.

Cheers,
Ben

> -----Original Message-----
> From: Gert Doering [mailto:gert at greenie.muc.de]
> Sent: Monday, March 15, 2010 3:29 AM
> To: Ben Basler (bbasler)
> Cc: Gert Doering; Cisco Mailing list
> Subject: Re: [c-nsp] Spanning-Tree vs. EoMPLS links in SXI2?
> 
> Hi,
> 
> On Mon, Mar 15, 2010 at 12:54:54AM -0700, Ben Basler (bbasler) wrote:
> > The question is if the ingress linecard has a DFC3B/BXL or DFC3C/CXL
> > or a CFC (and if a CFC if the Sup is a PFC3B/3BXL or PFC3C/3CXL).
You
> > might be hitting CSCtb41832 which from what I understand will be
> > resolved in
> > SXI4 and only applicable to 3C/CXLs.
> 
> Sounds complicated :-)
> 
>  - problematic router:
>     ingress line card is 6724-SFP with CFC
>     egress line card is 6708-10GE with DFC-3CXL
>     supervisor is a Sup720-10G-XL  (PFC3C/XL)
> 
>  - lab router, where I can not reproduce this:
>     ingress, egress and supervisor is Sup720-10G-XL (PFC3C/XL)
>     no DFC or CFC involved
> 
> Mmmh.  Reading up on the bug, I'm fairly sure that our case handler is
not
> going to find it (as it doesn't mention "STP") - but it certainly
smells
> similar "some special case PDUs are not being transported".
> 
> Can you share more details on the combination of PFC and CFC that
triggers
> this?  (In any case: thanks a lot for this pointer!)
> 
> gert
> --
> USENET is *not* the non-clickable part of WWW!
>
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> Gert Doering - Munich, Germany
gert at greenie.muc.de
> fax: +49-89-35655025
gert at net.informatik.tu-muenchen.de