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Good Afternoon,

I ran into an issue this morning where static routes on a certain device weren't being redistributed into an EIGRP process configured on the same device. I'd originally thought this was because the "default-metric" command (or it's route-map subcommand equivalent) wasn't in place. The issue ended up being due to licensure level on the device. It was a 4500X licensed for IPBase, and therefore auto-configured "eigrp stub connected summary" when we turned up the EIGRP process.

I fired up a GNS3 lab to check if redistribution from a static routing table into EIGRP needed the "default-metric" command, and routes redistributed just fine without it. From looking at different documents, they all say the default metric needs to be specified for redistribution from all routing processes spare another EIGRP or IGRP instance. Can anyone tell me why the routes are redistributed from static without a default-metric command, and what metrics are being used/why those metrics?

Thanks in Advance,

Phillip

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When one routing protocol is being redistributed into another, the router doesn't have a way to translate the routing metric from one routing protocol into another. Statics also fall in this category.

There are a couple of ways to redistribute statics:

1) network command http://www.cisco.com/c/en/us/support/docs/ip/enhanced-interior-gateway-routing-protocol-eigrp/16406-eigrp-toc.html#statictointerface

2) redistribulte static where you'd need a rule to calculate a metric default-metric which sets the default metric for redistributing other protocols into EIGRP.

It might be that in your GNS3 lab you used 1st method.

  • Alexey, Thank you for your response. I specified specific network statements to make sure the route I wanted to be redistributed wasn't covered by a network statement.. It would be advertised as internal in case 1. Routes that are being redistributed show up with code "D EX" meaning they are in the table via redistribution (2) instead of the network command (1) My question is, I didn't specify a "default-metric" in any way, and I am still getting redistributed static routes in my routing tables. Because the metric isn't specified, redistribution should not occur; I'm confused as to why it is. – S Phillip R Simonds Sep 9 '15 at 14:39
  • Anither thing to consider is that if you define static route with egress interface EIGRP might consider them as directly connected . Also there is some evidence that redistributing static routes into EIGRP also does not require setting the seed metric. The bandwidth & delay values of the egress interface of the static route is considered in the metric calculation, just like connected routes being redistributed into EIGRP link. – Alexey Smirnov Sep 9 '15 at 15:44
  • So you're saying that if no seed metric is set, the metrics ascribed to the route's egress interface are utilized? – S Phillip R Simonds Sep 9 '15 at 18:40
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A static route does not have a metric unless is redistributed into s dynamic routing protocol in that case the assignement of a metric is dependent on the particular routing protocol.

  • Hi. I agree. In the case of EIGRP on cisco routers, I believe you have to specify the metric (bandwidth, load, delay, reliability, MTU) otherwise EIGRP won't redistribute routes as it has no metric to do so with. EIGRP is redistributing, but I believe it shouldn't be as no metric is specified. So my question is, 1) Why is EIGRP redistributing when no specified metric exists and 2) What metric is it using to do so? – S Phillip R Simonds Sep 9 '15 at 14:44

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