Q169416: RIP Routes May Have a Different Metric Than Expected

Article: Q169416
Product(s): Microsoft Windows NT
Version(s): 4.0
Operating System(s): 
Keyword(s): kbnetwork
Last Modified: 09-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Server version 4.0 
- Microsoft Routing and Remote Access Service Update for Windows NT Server version 4.0 
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SUMMARY
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Routes learned from the Routing Information Protocol (RIP) may not have the
metrics that you would expect. When a Windows NT Router is advertising a non-RIP
route over RIP, it will always be advertised with a metric of 2.

MORE INFORMATION
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A metric is a value that shows how desirable a particular route is. Other
routing protocols give different meanings to the metric. Because the meanings
for the metric are different, the metrics cannot be directly converted. When RIP
advertises a non-RIP route, RIP will advertise the route with a metric of 2.

A simple example is a Windows NT router advertising its local subnet routes.
Routes for the locally attached LANs will show in the route table with a metric
of 1 and the Protocol is Local. This local route will be advertised to a
neighbor RIP router with the metric of 2. This neighbor router will then
increase the metric for all routes by one to reflect its own hop count to the
destination. In this neighbor's route table, you will see the metric of 3 when
you would expect to see the metric of 2.

Additional query words: RRAS
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Keywords          : kbnetwork 
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbAudDeveloper kbRRASNTSearch kbRRASNT400
Version           : 4.0

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