EIGRP Multipoint Bandwidth Pacing

Hi, could any one please tell me how to allocate bandwidth percents to point to multipoint connections and point-to-point to connections? Is there any specific method other than allocating them by ip bandwidth-percent cmd?

This lab confuses me because the ip addresses are configured under the physical interface. There are no multi-point interfaces configured. And the lab says not to change the framerelay configurations don't we need "frame-relay map" commands to reach full connectivity?

Hello James,

Good question. The whole EIGRP "bandwidth" pacing for frame-relay is an annoying topic if you ask me.

Everything is configured on the physical interface so the question is...what type of interface is the physical one? Is it point-to-point or multipoint?

The answer is that the physical interface is always a multipoint interface to frame-relay. You don't need frame-relay mappings because Inverse ARP will take care of that. You only need to do mappings yourself when you use sub-interfaces because the router doesn't know which DLCI belongs to which (sub)interface.

Does that make sense? Let me know if you have any more questions.

Rene

Rene,

Router Tilburg learned all Loopback networks:

2.0.0.0/24 is subnetted, 1 subnets
D 2.2.2.0 [90/2297856] via 192.168.1.2, 00:18:52, Serial0/0
3.0.0.0/24 is subnetted, 1 subnets
D 3.3.3.0 [90/2297856] via 192.168.1.3, 00:17:29, Serial0/0
4.0.0.0/24 is subnetted, 1 subnets
D 4.4.4.0 [90/2297856] via 192.168.1.4, 000:51, Serial0/0
5.0.0.0/24 is subnetted, 1 subnets
D 5.5.5.0 [90/2297856] via 192.168.1.5, 000:12, Serial0/0

All other routers only learned 1.1.1.0 loopback network from router Tilburg.

How can I get full connectivity on all the routers?

Thank you.

In order to get full connectivity I had to use 'no ip split-horizon eigrp' command under s0/0 interface, although split-horizon is disabled by default on physical interface:

Berlin#show ip route eigrp
1.0.0.0/24 is subnetted, 1 subnets
D 1.1.1.0 [90/2297856] via 192.168.1.1, 00:104, Serial0/0
2.0.0.0/24 is subnetted, 1 subnets
D 2.2.2.0 [90/2809856] via 192.168.1.1, 008:25, Serial0/0
4.0.0.0/24 is subnetted, 1 subnets
D 4.4.4.0 [90/2809856] via 192.168.1.1, 008:25, Serial0/0
5.0.0.0/24 is subnetted, 1 subnets
D 5.5.5.0 [90/2809856] via 192.168.1.1, 008:25, Serial0/0

Hi Dmitri,

Good that you found the solution. EIGRP is disabled by default on the physical interface, it will be enabled on sub-interfaces.

Not sure why i had split horizon enabled on the physical interface

Rene

Rene,

For the last question all I had to do is to set bandwidth to 256kbps on Tilburg and 64kbps on all other routers. Am I right?

Thank you.

Hi Dmitri,

That's correct. If you configure bandwidth on the physical interface it will be divided by the number of PVCs.

Rene

Rene, Is there anything special or any analogy to help you remember the bandwidth calculations for the different frame relay situations other than Brute Memorization?

@Thomas

I don't have an analogy to remember these for EIGRP & Frame-relay. I do have some for OSPF and frame-relay. I always forget about EIGRP frame-relay so i have to look it up ;D

Hey Rene',
last part of the question:

Configure your network so the bandwidth reflects the CIR on the PVCs and there are no congestion problems with EIGRP.

Why do we use 256 kb on Tilburg, based on what info that was given? Did you say that if you config the 256, it automatically splits it evenly and the other spokes dont need BW config? Note, split horizon was disabled on the physical interface, but had to use
Tilburg(config-router)# no ip split horizon eigrp 1 command
Thats specific for the eigrp updates correct?

Thanks, until next time
Joe

Hi Joe,

There's a single interface on router Tilburg (multipoint) and we have multiple PVCs with different CIR rates. If you configure multipoint interfaces EIGRP will divide the bandwidth / number of PVCs that you have. In this case the lowest CIR is 64kbps so we can set the bandwidth at 256kbps. 256 / 4 = 64kbps. We need to use the lowest CIR rate to be safe or router NewYork could be overburdened if it were any higher.

The "no ip split horizon" command is specific for EIGRP but I *think* split horizon is disabled by default on the frame-relay physical interface. It's something to be aware of when you use a sub-interface though.

I think I'll record the video for this one next week.

Rene

Thanks, that makes sense now.