topic dhcpd.conf domain search option example ? in Operating System - Linux

dhcpd.conf domain search option example ?

Al Licause — Fri, 09 Jun 2006 13:20:39 GMT

Does anyone have an example of a dhcpd.conf entry for the domain search option ?

The option allows for a list of domain names that can be passed to a client, allowing it to search those domains first when looking for a dns name or address.

I have found many articles on the internal format via rfc's but nothing showing an actual implementation. I'm begining to wonder if this option was ever implemented in any server or understood by any client ?

Re: dhcpd.conf domain search option example ?

Ivan Ferreira — Fri, 09 Jun 2006 13:56:23 GMT

This is what I have found:

The DHCP standard has no provision for that. You might want to check the archives of the ISC DHCP lists as this question comes up periodically there (particularly dhcp-server).

On the domain search order issue, there isn't a standard configuration
parameter or option that I know of which supports this.

http://lists.freebsd.org/pipermail/freebsd-current/2005-June/052215.html
http://lists.freebsd.org/pipermail/freebsd-current/2005-June/051634.html

Re: dhcpd.conf domain search option example ?

Al Licause — Fri, 09 Jun 2006 14:01:52 GMT

Ivan,

Thanks much for the quick reply. But when you say there is no dhcp standard for domain search, do you mean for the server or the client ?

I have found references to an rfc 3397 authored in November of 2002 which describes this feature.

Has this not yet been implemented on both client or server or either ?

Al

Re: dhcpd.conf domain search option example ?

Al Licause — Fri, 09 Jun 2006 14:29:19 GMT

Ivan,

Again thanks. The second reference you posted allowed me to come up with the following syntax in my dhcpd.conf file:

option domain-search-order code 119 = string;
option domain-search-order "domain1.net domain2.net domain3.net";

At least it allows dhcpd to start. As to whether or not it's serving this group of domainnames to the clients, that's more difficult to tell. And whether or not the clients will actually accept and do anything with these strings is another story.

Al

Re: dhcpd.conf domain search option example ?

Alexander Chuzhoy — Fri, 09 Jun 2006 15:41:18 GMT

I've never tried it-but worth a shut:

http://www.redhat.com/archives/redhat-list/2005-June/msg00239.html

Also:
If the client is a linux box, then make sure that you don't have such etry in your network interface configuration file:
PEERDNS=no
or better yet place an entry
PEERDNS=yes

Re: dhcpd.conf domain search option example ?

Al Licause — Mon, 12 Jun 2006 14:44:52 GMT

Alexander,

Thanks for the pointer. Unfortunately I've already tried this and the dhcpd server won't even start if you specify more than one domain on the domain-name line.

At least with the previoulsy listed option, I can start the dhcpd process.

Heard back from customer and he says it didn't load his Microsoft client....I'm waiting to hear back as to whether or not he saw the multiple domains in the offer from the server.

If they did, then there isn't much we can do if the client doesn't know what to do with the data.