Subject: Cisco's DVMRP Discovery ?

From: "Jesus Maria Arango - Ing. Comunicaciones FSM LTDA." <[email-masked]>
Date: Tue, 4 Mar 1997 16:27:39 +0500 (GMT)

Cisco manual says that it uses PIM but that it can discover DVMRP routers
and interoperate with them.

Does any body know the discovery mechanism used by IOS?

If I have 2 ciscos connected by a tunnel in dvmrp mode, will the
discovery mechanish work thus allowing both ciscos to interoperate in
DVMRP? or is this only usefull with non-cisco machines?

Thanks in advance for your help !!!  

  *****************************************
  *             Jesus Arango              *
  *      Ingeniero de Comunicaciones      *
  *  Supernet - FSM LTDA. - Cablesistema  *
  *        E-Mail: [email-masked]        *
  *       Internic POC Handle: JA406      *
  *          Tel: (574) 268-9000          *
  *          Fax: (574) 268-1281          *
  ****************************************

---

From: Chris White <[email-masked]>
Date: Tue, 04 Mar 97 14:23:10 PST

> DVMRP? or is this only usefull with non-cisco machines?

You cannot use DVMRP tunnels between two cisco's, you can however use a GRE
tunnel. The discovery of DVMRP routers is only useful for interoperating
with non-cisco machines, as you said.

-Chris

---

From: "Daniel A. Alvarez" <[email-masked]>
Date: Tue, 04 Mar 1997 14:35:09 -0800

> DVMRP? or is this only usefull with non-cisco machines?

	DVMRP tunnels are not supported between two ciscos.
	For documentation on cisco's implementation please look
	in ftp://ftp-eng.cisco.com/ipmulticast

	You can address cisco specific questions to [email-masked]

dan

---

From: "John M. Zwiebel" <[email-masked]>
Date: Tue, 04 Mar 1997 14:57:12 -0800

Cisco does not support DVMRP tunnels between two cisco routers.
Cisco does support DVMRP tunnels to mrouted routers.
Cisco does support GRE tunnels between two cisco routers.

---

From: "Jesus Maria Arango - Ing. Comunicaciones FSM LTDA." <[email-masked]>
Date: Tue, 4 Mar 1997 17:53:45 +0500 (GMT)

> with non-cisco machines, as you said.

I am also having problems with GRE tunnels that I use for other purposes.
I want to know how can I get cisco's support for this and if I have to pay
for it?

By the way, the problem with the tunnel is the following:

      Ethernet             Point to Point            Ethernet
  --------------------RA---------RB------------RC-------------------
        |                                               |
        |                                               |
        HA                                              HC

I have a tunnel between routers RA and RC. Both are ciscos. RB is an
ascend mx 1800. Tunnel traffic from RA to RC only goes through when
packets originate from RA. If host HA tries to send a packet through the
tunnel, the packet only gets to RA. The opposite is not happening: Both
router RC and host HC are able to transmit packets through the tunnel
succesfuly. There are no route problems. Both tunnels are configured in
the default mode. The only difference I see is that both ciscos are
running diferent IOS version (RA=11.1(9) and RC=11.0).

Does anyone know what could be wrong or point me out to someone who can
help me?

Thanks in advance

---

From: Toerless Eckert <[email-masked]>
Date: Wed, 5 Mar 1997 00:01:31 +0100 (MET)

cat > /var/spool/reminder << EOF
Cisco does not support DVMRP tunnels between two cisco routers.
Cisco does support DVMRP tunnels to mrouted routers.
Cisco does support GRE tunnels between two cisco routers.
EOF

cat >> /var/spool/cron/crontabs/root << EOF
2 0 * * 1,3 /usr/ucb/Mail -s "DVMRP and Cisco reminder" [email-masked] < /var/spool/reminder
EOF

*sigh*