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Can I terminate my serial link into the same Cisco router? I mean can I terminate both ends of serial (wan) link into the same router's two different serial ports? This is just for testing purposes.


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What do you expect to happen when you do that? – pjc50 Nov 25 '09 at 14:28

thats not possible as the interfaces on the routers have to be in different subnets, but the interfaces at two ends have to be in same subnets..... so you see the two statements are contradictory....

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Huh? Could you restate what you're trying to say? – joeqwerty Nov 25 '09 at 17:09
OK, I got it. I wasn't following your wording. – joeqwerty Nov 25 '09 at 17:28

No two interfaces IPs on the same router can be in the same subnet(on most vendors anyway). The interfaces on each end of a serial connection must be in the same subnet. So no you cannot do this.

If you wish to do this on Cisco IOS without hardware I would suggest you look into something like GNS3 or Dynamips.

Edit: Actually if you were using IPv6 and link local addresses you probably could do this, but if you're using IPv4 IOS is going to scream at you.

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