Frame Relay Question

Shanman

When setting up your frame relay switch do you have to use the frame relay route command and setup the routes statically all the time? Is there a way of this happening dynamically.

NetAdmin84

I'm not 100% sure on this, but I'm pretty sure that by configuring Frame-Relay, by default the mappings are created dynamically -

R1#show frame map

Serial0 (up): ip 200.1.1.2 dlci 122(0x7A,0x1CA0), dynamic, broadcast,, status defined, active

Serial0 (up): ip 200.1.1.3 dlci 123(0x7B,0x1CB0), dynamic, broadcast,, status defined, active

In order to assign static routes you must:

Disable inverse arp at the interface configuration prompt -

R1(config-if)#no frame-relay inverse-arp

Next, you must use the frame map statements -R1(config-if)#frame map ip 200.1.1.2 122

Also, be sure to add the keyword broadcast to the end of your static mappings to allow broadcast to cross the frame-relay -

R1(config-if)#frame map ip 200.1.1.2 122 broadcast

The frame-relay map command should read as follows after assigning static routes -

R1#show frame map

Serial0 (up): ip 200.1.1.2 dlci 122(0x7A,0x1CA0), static, broadcast, CISCO, status defined, active

Serial0 (up): ip 200.1.1.3 dlci 123(0x7B,0x1CB0), static, broadcast, CISCO, status defined, active

Hope this helps!

Shanman

Yes I understand that but I am talking on the frame relay switch itself. Do I need to do a frame relay route or can that be done dynamically.

QHalo

This should help you out.

Frame Relay Switch Configuration For Cisco Lab

Shanman

That is the course I am using for my studies. I am curious about the frame relay cloud itself. When you have the router enabled with frame relay switching. Must you set the routes on the frame relay switch (DCE) end of the connection? This can be done with the frame relay route command. This would become very labor intensive as your frame relay cloud grows. You must be able to have it populate the routes dynamically. If not I can't imagine the work it would take for the ISP to keep all of these static routes configured.

QHalo

Dymanic Frame relay updates are done using Inverse ARP however that is only on the DTE side. The DCE side is still manually configured from what I can find and I kind of get that because you're leasing a PVC with the service provider so it would be configured statically on their end.

Perhaps someone with more service provider experience can debunk that theory but that's what I get from all the documentation I can find.