Setting up route redundancy using EIGRP

[GRANT GATHAGAN]

I'm trying to set up some redundancy to a remote location via EIGRP and I'm stuck on whether or not any static routes or default gateways should be included in any of the switches located at that location.

Up until recently, the sole route to the site was through a T1 line.

We now have gigabit radio link between the main campus and a 2nd remote site, as well as a gigabit radio link between the two remote sites

So I now have the two routes to the remote campus 1 as show below.

main campus ------------------------------- T1 --------------------------- remote campus 1

main campus---- 1.2Gbps ---remote campus 2---- 1.2Gbps ----remote campus 1

These aren't my real IP subnets, but my main campus uses 192.168.30.xxx/23, remote campus 1 uses 192.168.36.xxx/23 and remote campus 2 uses 192.168.40.xxx/23.

My router links all use 192.168.50.xxx/30.

Most of the current EIGRP statements are the same on all devices:

router eigrp 100

network 192.168.0.0

no auto-summary

The routers also add:

"eigrp log-neighbor-changes"

and

"redistribute static"

Most of the switches have "eigrp stub connected summary", but some do not.

Some also have "redistribute static" and some do not.

So I have four questions:

1) If I am using EIGRP routing, should there be any any static routes or default gateways settings in any of my switch or router configurations?

2) If I want to keep the T1 line as a fallback connection, how do I configure the connections so that the faster connections is the route of choice; change AD/metrics on the slower-but-more-direct connection or some other mechanism?

3) In all of my current router/switch configurations, auto-summarization is disabled.

Should I enable it?

4) Should all of my network statements be "network 192.168.0.0" or should there be multiple network statements with the smaller subnets identified, depending on which router is involved?

network 192.168.30.0

network 192.168.40.0

network 192.168.36.0

[John Blakley]

Grant,

So I have four questions:

1) If I am using EIGRP routing,  should there be any any static routes or default gateways settings in  any of my switch or router configurations?

You can use statics to do some traffic engineering if you want to go one direction vs another. Your static will take precedence because of the AD that statics have (1 vs 90)

2)  If I want to keep the T1 line as a fallback connection, how do I  configure the connections so that the faster connections is the route of  choice; change AD/metrics on the slower-but-more-direct connection or  some other mechanism?

You can change the delay on the T1 to make your other connections prefered. You'd do this directly on the interface. Don't change bandwidth statements on your interfaces because those also affect other things like qos.

3) In all of my current router/switch configurations, auto-summarization is disabled.

Should I enable it?

Don't enable it. It's safer to leave it with no auto-summary

4)  Should all of my network statements be "network 192.168.0.0" or should  there be multiple network statements with the smaller subnets  identified, depending on which router is involved?

network 192.168.30.0

network 192.168.40.0

network 192.168.36.0

I would keep them separated like this for the ease of reading...

[GRANT GATHAGAN]

Thanks for the quick response, John,

I'll be the first to admit that I know just enough about routing to be dangerous, so some of my "Aha!" moments are probably routing basics.

I am currently using static routes and gateway of last resort statements, but one of my goals was to set the system up to automatically fail over to the T1 line if something happened to the radio links.

I can do that in fairly quick order manually, but it'd be nice if I knew it would failover while I'm on vacation.

To this point, I've concentrated on data traffic only, but I also want to route my voip traffic through the same pathway. Currently VoIP traffic to remote site 1 is still being routed over the T1.

I've made a picture of the current setup.

Here are the route-related statements in all of the various devices:

6506/SUP1A engine:

ip route 192.168.36.0 255.255.254.0 192.168.50.2

ip route 192.168.50.0 255.255.255.252 192.168.40.7

router eigrp 100

redistribute static

network 192.168.0.0

no auto-summary

eigrp log-neighbor-changes

Main campus 1760V:

router eigrp 100

redistribute static

network 192.168.0.0

no auto-summary

Main campus 3750E:

  router eigrp 100

redistribute static

no auto-summary

eigrp stub connected summary

network 192.168.0.0

ip default-gateway 192.168.30.1

ip route 0.0.0.0 0.0.0.0 192.168.30.1

Remote site 1 1760V:

router eigrp 100

redistribute static

network 192.168.0.0

no auto-summary

ip route 0.0.0.0 0.0.0.0 192.168.50.1

Remote site 1 - 3750_1:

router eigrp 100

network 192.168.0.0

redistribute static

eigrp stub connected summary

ip route 0.0.0.0 0.0.0.0 192.168.50.1

Remote site 1 - 3750_2:

router eigrp 100

network 192.168.0.0

redistribute static

ip route 0.0.0.0 0.0.0.0 192.168.40.7

Remote site 2 - 3750E_1:

router eigrp 100

redistribute static

no auto-summary

eigrp stub connected summary

network 192.168.0.0

ip default-gateway 192.168.30.1

ip route 0.0.0.0 0.0.0.0 192.168.30.1

Remote site 2 - 3750E_2:

router eigrp 100

no auto-summary

eigrp stub connected summary

network 192.168.0.0

ip default-gateway 192.168.40.1

ip route 0.0.0.0 0.0.0.0 192.168.40.1