RE: Dhcp, relay and option 82

Check this post, hope it clarifies you the issue.

http://www.netcontractor.pl/blog/?p=177

Cheers,

Dominik Nowicki, CCIE R&S #24543

Cisco Network Consultant

NetContractor

tel.: +48 606-711-009

 <mailto:dominik.nowicki_at_netcontractor.pl> dominik.nowicki_at_netcontractor.pl

 <http://www.netcontractor.pl/> www.netcontractor.pl

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Antonio Saez
Sent: Friday, July 16, 2010 10:55 AM
To: nobody_at_groupstudy.com; ccielab_at_groupstudy.com
Cc: 'Antonio Saez'
Subject: Dhcp, relay and option 82

Hi all,

I am going deeper in my dhcp understanding and have one question

?is it possible for a router relay agent to keep the information option 82

but set the giaddr field?

If I have understood well the information option, when one dhcp snoop and

option 82 enabled switch is connected to a dhcp relay router, the giaddr

field is set to 0s by the witch. If the relay trust the information option,

the giaddr field keep to 0. In this case the dhcp server always has to

derive the client IP from the 82 option, am I right? It is a little bit

confusing;)

Regards

Blogs and organic groups at http://www.ccie.net
Received on Fri Jul 16 2010 - 22:29:31 ART