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ODR should be a very simple feature.

I have a FR hub and spoke where R4 is hub and R5 is spoke. R4 receives prefixes from spoke but the spoke does not receive any default route from the hub.

CDP looks fine, when I debug CDP I see that hub is generating a default but it's not sending it out the serial interface. Any ideas?

I know if there is ANY routing protocol configured on the spoke, it will not install the ODR default

If CDP is wroking and you can see the enighbor, ODR should work. Only thing is CDP is by default not enabled on multipoint interface/sub-interface, we should manually enable on it.

interface Serial0/0/0.2 point-to-point
 frame-relay interface-dlci 504 ppp Virtual-Template1

Serial0/0/0.2 is up, line protocol is up
  Encapsulation FRAME-RELAY
  Sending CDP packets every 60 seconds
  Holdtime is 180 seconds

R5#sh ip prot

*Jun 28 19:25:56.810: CDP-IP: Writing prefix 120.1.5.5/32
*Jun 28 19:25:56.810: CDP-IP: Writing prefix 120.100.40.0/24

Just can't find why I'm not receiving the default. R4 does not send it out the interface to R5 (Virtual-template 1).

What does the config look like on R5? Is frame-relay configured on the main interface of R5? Can you actually see R4 when you "show cdp neighbor" ? 

Both R4 and R5 were running PPPoFR. They could see each other as CDP neighbors.

ODR needs to be running on the hub router only.

daniel.dib:

Both R4 and R5 were running PPPoFR. They could see each other as CDP neighbors.

Hi Daniel

We need to enable cdp on virtual-template if PPPoFR is running, in this case it does matter whether cdp is enabled on physical interface or not. But if cdp is enable on both physical interface and virtual template, the hub will have two routes installed for same destination one via virtual -access and other via physical interface. Though this does not make any difference whether two routes are install or just one because ultimately even virtual-access is also using physical interface for packet forwarding. And obviously spokes will have a default route advertise by hub.

Thanks,

I'll try to lab it up with PPPoFR and manually enabling CDP.

OK, so I labbed it up. For anyone interested just connect two routers in GNS3 via frame switch and run PPPoFR between them.

If I run default settings, CDP enabled on physical interface then the hub router does get the prefixes announced by the spoke. If I enable CDP with cdp enable on virtual-template of hub nothing changes. If I enable CDP on spokes virtual-template then ODR starts working.

*Mar  1 00:11:41.779: CDP-IP: Reading default route 120.1.1.1 via Virtual-Access1
*Mar  1 00:11:41.779: CDP-IP: Updating default route 120.1.1.1 in routing table

So the conclusion is to enable CDP manually when running PPPoFR.

Thanks for pointing me in the right direction dcancerian.

daniel.dib:

OK, so I labbed it up. For anyone interested just connect two routers in GNS3 via frame switch and run PPPoFR between them.

If I run default settings, CDP enabled on physical interface then the hub router does get the prefixes announced by the spoke. If I enable CDP with cdp enable on virtual-template of hub nothing changes. If I enable CDP on spokes virtual-template then ODR starts working.

*Mar  1 00:11:41.779: CDP-IP: Reading default route 120.1.1.1 via Virtual-Access1
*Mar  1 00:11:41.779: CDP-IP: Updating default route 120.1.1.1 in routing table

So the conclusion is to enable CDP manually when running PPPoFR.

Thanks for pointing me in the right direction dcancerian.

 

that would make sense since CDP is a link level protocol so you'd need it at the link level

the virtual template takes logical configurations...i doubt the cdp enable cmd on the virtual-template gets picked up by the cloned virtual access interface

i doubt CDP enabled on the spoke virtual templates is helping...you only need it on the hub...remove it and it should still work

..just my 2 cents 

Tox!