[c-nsp] EoMPLS between subinterface and physical interface

Arie Vayner (avayner) avayner at cisco.com
Tue Aug 18 11:19:51 EDT 2009


Well, you could use a loopback cable solution (not the prettiest
solution around).
So on 7600-2 you use a trunk port with multiple sub-ifs (like on 7600-1)
but loop it back to a regular l2 trunk port. Then you just connect the
CPE's to regular access ports on the VLANs.

What I am not sure is whether the 7600 would even allow you to put an
access port on the same VLAN used on the sub-if. No quick way for me to
test it right now.

Also, if it even works, you would be doing MAC learning on 7600-2, as
the CPEs are attached to access ports...

The right solution for this kind of service would be to use ES20/ES40
and EVCs.

Arie

-----Original Message-----
From: Tassos Chatzithomaoglou [mailto:achatz at forthnet.gr] 
Sent: Tuesday, August 18, 2009 12:19
To: Arie Vayner (avayner)
Cc: cisco-nsp
Subject: Re: [c-nsp] EoMPLS between subinterface and physical interface

Arie,

I'm actually trying something strange in the lab, but i wanted to ask
opinions before
trying all the alternatives.

More specifically i want to transfer double tagged traffic from multiple
subifs of a local 
MUX-UNI interface to multiple remote physical interfaces, where the
outer tag would be 
removed.

CPE <===> 3750 <===> 7600-1 <= MPLS-network => 7600-2 <===> CPE-x


Something like:

7600-1
------
int gi1/1
  desc conn to 3750
  switch mode trunk		! these are single-tagged vlans
following another path
int gi1/1.100
  enc dot 100			! this is double-tagged that needs to be
tunneled
  xconnect x2.x2.x2.x2 y1
int g1/1.200
  enc dot 200			! this is double-tagged that needs to be
tunneled
  xconnect x2.x2.x2.x2 y2

7600-2
------
int gi1/1
  desc conn to CPE-1
  xconnect x1.x1.x1.x1 y1
int gi1/2
  desc conn to CPE-2
  xconnect x1.x1.x1.x1 y2

So double-tagged traffic having an outer vlan of 100, would get
transfered from 7600-1 
gi1/1.100 to 7600-2 gi1/1, where it would/should have the outer vlan
removed. It's 
actually like many L2 VPNs starting from one port on 7600-1 and ending
at many ports (each 
one on its own) on 7600-2.



-- 
Tassos



Arie Vayner (avayner) wrote on 17/08/2009 21:57:
> Tasso,
> 
> What are you trying to achieve?
> 
> Arie
> 
> -----Original Message-----
> From: cisco-nsp-bounces at puck.nether.net
> [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Tassos
> Chatzithomaoglou
> Sent: Monday, August 17, 2009 20:04
> To: cisco-nsp
> Subject: [c-nsp] EoMPLS between subinterface and physical interface
> 
> I'm reading under EoMPLS Guidelines and Restrictions
>
http://www.cisco.com/en/US/docs/routers/7600/ios/12.2SR/configuration/gu
> ide/pfc3mpls.html#wp1109041
> 
> ======================================
> For a particular EoMPLS connection, both the ingress EoMPLS interface
on
> the ingress PE and the egress EoMPLS interface 
> on the egress PE have to be subinterfaces with dot1Q encapsulation or
> neither is a subinterface.
> ======================================
> 
> So, i guess in PFC-based EoMPLS you can't have a subinterface on one
> side (vlan mode) and a physical interface (port 
> mode) on the other side.
> 
> Besides using ES/SPA cards and scalable EoMPLS on both sides, is there
> another solution?
> 
> What about scalable EoMPLS on one side and PFC-based EoMPLS (vlan or
> port mode) on the other? Has anyone tried it?
> 
> --
> Tassos
> _______________________________________________
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> https://puck.nether.net/mailman/listinfo/cisco-nsp
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