Connected routes

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Jan 17th, 2008
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I was asked if a router can route between connected subnetworks just after its startup & loading. No configuration was added. Does anyone knows if that can happen?

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Jon Marshall Thu, 01/17/2008 - 12:52
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Hi


Do the interfaces on the router have ip addresses assigned ?


Jon

MachadoGB Fri, 01/18/2008 - 05:13
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Hi Jon,

The answer to your question is no.

So as you can see by the replies below there will be no routing going on unless you have the IP address configured and the interfaces are not in admin down state.


Thanks for your reply.

Gilson

pciaccio Thu, 01/17/2008 - 12:53
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Just after its startup and with no configuration in it a router will not route packets between its interfaces. Routing is enabled by default but no interface parameters are on the configuration. Once you have IP addresses on the interfaces then it will route to directly connected interfaces only.

Richard Burts Thu, 01/17/2008 - 14:50
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Gilson


In addition to the points made by Jon and Phil, if the router just booted up and no configuration was added it is very likely that the interfaces are in the admin down state. This would also prevent routing between the interfaces.


HTH


Rick

MachadoGB Fri, 01/18/2008 - 05:07
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Rick,

Thanks for the reply - yes you are correct. When you first boot a router the interfaces are in the admin down state and the routing will not happen.


Regards,

Gilson

MachadoGB Fri, 01/18/2008 - 05:09
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Yes, you are correct - if you do not configure the ip address ubder the interface you want to route it will not route (layer 3 is not active).

Thanks for your reply.

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