Supported format for Client Identifier.

Simon Hobson dhcp1 at
Wed Jun 17 08:43:08 UTC 2009

pat wrote:
>Does this mean ISC DHCP server supports RFC 4361 format and when the 
>client send the Option 61 with RFC 2132 format the Server supports 
>the option ??
>if it so what happens in the scenario of client sending the option 
>61 in RFC 4361 format and the server supports only RFC 2132 ??

The ISC server (at least up to version 3.x) doesn't "do" anything 
with the Client ID other than use it as a database key. Ie it doesn't 
care what you use, and it doesn't look inside it, it just stores it 
and uses it as a string of bytes. I was under the impression that the 
V4 server is the same.

In the IPv4 world, most clients don't actually send a Client ID at 
all, only Microsoft decided it should be the hardware address. As 
David W Hankins said yesterday :
>You may safely use quotations from _War & Peace_ as your client
>identifier (barring packet size limitations).  ISC dhcpd won't mind.

Simon Hobson

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