Subject: pim-to-dvmrp problems

From: [email-masked] (Craig M Votava)
Date: Wed, 1 Jan 1997 11:49:26 -0600

Folks-

I'm looking for some help in figuring out the problem we're having here
trying to get a cisco router to route multicast packets with a PowerHub
router.

The PowerHub wants to do DVMRP routing, and we believe that we've followed
all of the instructions properly, to tell our cisco router (version 11.1)
to connect with it in dense mode, but things still don't seem to be working.

We see that the PowerHub seems to recognize the cisco as a router, and
starts routing to it, according to our mrinfo output:

1.1.1.2 (powerhub) [version 2.0]:
  1.1.1.2 -> 1.1.1.1 (cisco) [1/1/querier]

But the cisco doesn't seem to recognize the powerhub:

1.1.1.1 (cisco) [version 11.1,prune,mtrace]:
  1.1.1.1 -> 0.0.0.0 (local) [1/4/pim/querier]

Any suggestions? We've had the cisco guy out once to try and figure things
out, but he wasn't able to. We hope to get him back soon, to finish the job.

Any help is appreciated.

Thanks

-Craig

	()_()	Craig Votava
	 (_)	Lucent Technologies
		[email-masked]

---

From: Manoj Leelanivas <[email-masked]>
Date: Thu, 2 Jan 1997 09:40:02 -0800 (PST)

=>    We see that the PowerHub seems to recognize the cisco as a router, and
=>    starts routing to it, according to our mrinfo output:
=>    
=>    1.1.1.2 (powerhub) [version 2.0]:
=>      1.1.1.2 -> 1.1.1.1 (cisco) [1/1/querier]
=>    
=>    But the cisco doesn't seem to recognize the powerhub:
=>    
=>    1.1.1.1 (cisco) [version 11.1,prune,mtrace]:
=>      1.1.1.1 -> 0.0.0.0 (local) [1/4/pim/querier]
=>    
=>    Any suggestions? 

For a start, please turn on "debug ip dvmrp" on the cisco, when you do
an mrinfo and check if you see debug messages for the Ask-Nbr-2 request
and response.

Please contact us at [email-masked] with details of the
topology, your cisco's config etc and we may be able to provide
further assistance.

-Manoj

---

From: Bill Fenner <[email-masked]>
Date: Fri, 3 Jan 1997 01:57:00 PST

>  1.1.1.1 -> 0.0.0.0 (local) [1/4/pim/querier]

This is "normal", due to Cisco's incomplete DVMRP implementation.
e.g.:

204.162.228.1 (parc.dart.net) [version 3.8]:
  204.162.228.1 -> 204.162.228.251 (disco-dart.parc.xerox.com) [1/1/querier]
  204.162.228.1 -> 204.162.228.7 (dodgedart) [1/1/querier]

204.162.228.251 (disco-dart.parc.xerox.com) [version 11.1]:
  204.162.228.251 -> 0.0.0.0 (local) [1/32/pim/querier]

The only way I know to figure out if the Cisco sees the DVMRP neighbor
is to use "show ip dvmrp route" to see if it has learned routes from it,
or, if it's the only neighbor, "show ip igmp interface <foo>" will say
something like

  DVMRP/mrouted neighbors present for 5w2d
     [version mrouted 3.8] [flags: GPM]

In any case, you're probably getting at least partially stung by the
fact that the 2.0 implementation of DVMRP didn't support a default route.
Alantec/Fore apparently has a newer implementation that you can get
which claims to implement the features of mrouted 3.8 (except for multicast
traceroute).  Since most configurations of stub DVMRP clouds hanging off
of PIM clouds use the default route, this probably explains why it doesn't
seem to be working.

  Bill

---

From: Anh Vu <[email-masked]>
Date: Fri, 3 Jan 97 10:32:20 PST

Craig,

If you contact our TAC, you can get a patch version of the 2.0 implementation
that will support the default route.

We do have a newer implementation that supports the features of mrouted
3.8, but it's in Beta right now.

Anh