re: route summarization

[lazon]

I have 4507R multi-layer switch and EIGRP is configured for dynamic routing.

router eigrp 101

network 10.223.12.0 0.0.3.255

network 10.223.17.0 0.0.0.255

network 10.223.18.0 0.0.0.255

network 192.168.1.0

network 192.168.10.0

auto-summary

By default EIGRP's auto-summarization is ON, based on the configuration above, I want to disable auto-summarization as the network defined were not contigous network. Please advice if the steps I want to take is appropriate. I am also attaching the configuration of our 4507R core switch. Any advice that will help optimize our core switch is greatly appreciated. Thanks.

[Istvan_Rabai]

Hi Narciso,

If you have a discontiguous network, it is a good idea to disable auto-summary with the no auto-summary command.

However, you should look at the possibility to manually summarize wherever possible.

I looked at the config of your switch and I don't see big problems in it. Of course it also depends on your environment. As this is a core switch, I suppose it is not alone in the network and it must co-operate with other switches and routers.

If you provide info about your environment (i.e. surrounding switches and routers), I think I will be able to tell you more about any expected problems in your configuration.

What I discovered is the following:

- interface vlan 500 has no ip address, so hosts in vlan500 will be isolated from the rest of the network.

- you have the

vlan access-map 17 10

action forward

I suppose you want to do some traffic filtering with it. You should then configure an access-list and apply it to the vlan acl with the "match ip address" command. Also you will have to apply the vlan acl to the appropriate vlan with the "vlan filter" command.

Cheers:

Istvan

[lazon]

Hello Istvan,

We have Concentrator and Router connected to this core switch and also L2 2950 switches. Dis-regard the vlan 500 interface right now. We have 2 seperate network ex. 10.223.17.0 subnet (old) and 10.223.12.0 subnet which is the new one. What I want to do is make these 2 seperate network communicate with each other. Based on the attached config is it possible to do this?, and wether the EIGRP auto summarization is appropriate to use. Thanks again.

-chie

[Istvan_Rabai]

Hi Narciso,

I see now.

Routing will definitely work, but as long as these 2 networks are directly connected to the 4507 switch, you actually don't need to use EIGRP for routing between these 2 vlans.

The switch should be able to do routing out of the box between vlan12 and vlan 17.

A routing protocol is needed if you want to make your switch or router learn about subnets located on other routers and switches.

For local routing you don't have to use a routing protocol. You just have to make sure the 'ip routing' command is issued in global config mode. (This is the default, so it cannot be seen in your running-config you provided).

Cheers:

Istvan