matching vendor-encapsulated-options?

Glenn Satchell Glenn.Satchell at
Thu Mar 23 11:25:15 UTC 2006

>Date: Wed, 22 Mar 2006 14:01:08 +0100
>From: "Johan Berglund" <bergis42 at>
>To: dhcp-users at
>Subject: matching vendor-encapsulated-options?
>Dear Sirs,
>I'm trying to match clients based on information in the option 43
>My goal is to be able to send the correct filename depending on the clients
>software version.
>The clients are sending their current version as a option 43 suboption along
>with other information.
>I've played around with option spaces but that is just for send encapsulated
>options _to_ the client or am I wrong?
>I would like to do something like this:
>option space vendor;
>option vendor.swversion code 12 = text;
>vendor-option-space vendor;
>if substring (option vendor.swversion, 0, 9) = "Version 2" {
>   filename "swversion3.boot";
Have you actually tried this? I think it might just work as you're not
assigning anything to the option, but rather reading from it.

The dhcp-options man page is not entirely clear on this point. However,
I have used "if exists option ..." to see if the client sent it and
this does work.


More information about the dhcp-users mailing list