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Re: More 6509 problems...

  • From: Rodney Dunn
  • Date: Thu Feb 01 22:56:16 2001

Danny,

You are correct.

In later code you cannot disable dCEF either.

hth,
rodney


 
On Tue, Jan 30, 2001 at 08:27:24PM -0600, Danny Snyder wrote:
> Now that I think about it, I was given somewhat of an explanation of what
> was happening.....I didn't remember until now though.
> 
> Basically the MSFCs act as the route processors for the 6509s.  A simple
> description of what these do is inter-VLAN routing.  If you look at show
> trunk off of the Supervisor engine on a 6509, you see that there is an ISL
> trunk from the supervisor to the MSFC.  In an ethernet-only environment,
> this is no big deal and is fairly straight-forward.  In the case of the
> FlexWAN modules, the switch creates a "hidden" VLAN- that is a VLAN numbered
> outside the allowed range for VLAN ids.  If for some reason this VLAN cannot
> be created and associated with the serial (or other interface off of the
> FlexWAN), the circuit shows as being up/down when it should be up/up because
> the communication between the FlexWAN module and MSFC isn't happening
> correctly.
> 
> With IOS 12.1.3aE4 (also earlier versions, but I'm not sure how much
> earlier) on the MSFC, cef is enabled and cannot be turned off.  Again, this
> does not present a problem for an ethernet network.  With the FlexWAN,
> distributed cef must be enabled for the hidden VLAN to be created correctly.
> There are debugging commands to see what is going on with the hidden VLANs,
> but you cannot get information about these through non-debugging commands.
> Once the hidden VLAN is created correctly, the interface can go up/up since
> communication between the FlexWAN and MSFC is then allowed to happen.
> 
> I didn't ask for details as to what specifically happens with distributed
> cef turned vs. having it turned off, and I was really suprised that not
> having *one* global configuration command was causing all of my problems....
> 
> That's everything I can recall about this....hope that helps.
> 
> --Danny
> 
> 
> 
> 
> -----Original Message-----
> From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of
> Rodney Dunn
> Sent: Thursday, February 01, 2001 5:22 PM
> To: Danny Snyder
> Cc: Kenny Sallee; agudgeon@firstnet.co.uk; nanog@merit.edu
> Subject: Re: More 6509 problems...
> 
> 
> 
> Danny,
> 
> The interface status should be independent of
> the swithcing path.  I've never seen the line
> state be affected by the switching mechanism
> (although I have seen the opposite).
> 
> Can you email me the case# you had so I can take
> a look?
> 
> rodney
> 
> 
> On Tue, Jan 30, 2001 at 02:22:21PM -0600, Danny Snyder wrote:
> >
> > Ya got me on that one....Cisco didn't really say why and I didn't think to
> > ask them either....
> >
> > --Danny
> >
> >
> >
> >
> > -----Original Message-----
> > From: Kenny Sallee [mailto:k_sallee@yahoo.com]
> > Sent: Tuesday, January 30, 2001 11:28 AM
> > To: agudgeon@firstnet.co.uk; 'Danny Snyder'
> > Cc: nanog@merit.edu
> > Subject: Re: More 6509 problems...
> >
> >
> > How would CEF cause an interface to be up/down?  Just curious....Kenny
> >
> > ----- Original Message -----
> > From: "Alison Gudgeon" <agudgeon@firstnet.co.uk>
> > To: "'Danny Snyder'" <dsnyder@nowdocs.com>; <nanog@merit.edu>
> > Sent: Tuesday, January 30, 2001 8:36 AM
> > Subject: RE: More 6509 problems...
> >
> >
> > >
> > > Hi
> > >
> > > Hybrid IOS
> > >
> > > I've got IP CEF DISTRIBUTED set globally.  Did you have it enabled or
> > > disabled on the T3 interface?
> > >
> > > Ali
> > >
> > > -----Original Message-----
> > > From: Danny Snyder [mailto:dsnyder@nowdocs.com]
> > > Sent: 30 January 2001 16:21
> > > To: agudgeon@firstnet.co.uk; nanog@merit.edu
> > > Subject: RE: More 6509 problems...
> > >
> > >
> > > Alison,
> > >
> > > I've had VERY similar problems with a 6509 (Sup 1a + MSFC2) with a
> FlexWAN
> > > and a PA-2T3+.  After spending the better part of two weeks on the phone
> > > with Cisco, we finally determined that ip cef distributed needed to be
> > > turned on in global configuration.
> > >
> > > Also, are you running native IOS or Catalyst OS on the Supervisor and
> IOS
> > on
> > > the MSFC ?
> > >
> > > Danny Snyder
> > > Network Administrator
> > > NowDocs, Inc.
> > >
> > >
> > >
> > >
> > > -----Original Message-----
> > > From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of
> > > Alison Gudgeon
> > > Sent: Tuesday, January 30, 2001 10:18 AM
> > > To: nanog@merit.edu
> > > Subject: More 6509 problems...
> > >
> > >
> > >
> > > Hi,
> > >
> > > Is anyone doing the following:
> > >
> > > 6509 (supervisor 1a + msfc) - with a flexWAN adapter to take a Packet
> Over
> > > Sonet OC-3 card.
> > >
> > > I'm having great problems getting up/up on the interface, the current
> > > situation is up/down, a hardware loop at the telco kit brings the line
> > up/up
> > > but otherwise just up/down.  Config is default I've just put IP's on.
> > >
> > > I'm running very new code - 12.1(4)E1
> > >
> > > many thanks in advance for any help.
> > >
> > >
> > > Kind Regards
> > >
> > >
> > > Alison
> > >
> > >
> >





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