asked on

DHCP server options 005 and 006 - what's the difference?

Hi experts!

When I setup a Windows DHCP server I always used the the option "006 DNS Servers" to automatically assign DNS server addresses to the clients. Recently I found a server where both, "005 Name Servers" and "006 DNS Servers" were configured with the same values. Does someone know what's the difference between these options? Until now I never had problems when only configuring the 006 option. Are there any environments where it's necessary to set both options?

Thanks in advance!
ghana

chad

Check this link regarding information about 005 - name servers
https://www.experts-exchange.com/questions/20997486/Windows-Server-2000-DNS-Xp-clients.html
let me know if you have any questions
Hope this helps
KaBaaM

sirbounty

I thought it had more to do with whether the server was authoritative or cache-only...
I wonder if it's more for backward-compatibility - we do not use 005 in our network (so I don't believe it's necessary as is suggested in the link you provided kabaam)...

I'll admit, I'm not 100% certain though - interested to see what other experts post here...

ghana

ASKER

kabaam, I found a similar PAQ where adding "005 Name Servers" resolved a DNS name resolution problem. Until now I've never used this option and never had those problems. But I don't have deep experience with XP and Server 2003 because most of the clients still run Windows NT 4.0 and 2000. It seems that it is necessary in some environments to use the 005 option. I want to know why...? There must be somewhere on the web an explanation - but I couldn't find it.

At the moment I fully agree with sirbounty regarding backward-compatibility. I thought it is some kind of 'very old' configuration when the internet was called arpanet....

ASKER CERTIFIED SOLUTION

oBdA

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

sirbounty

Perhaps it is also or maybe more for non-Microsoft name servers.
That would make more sense as well...

oBdA

sirbounty,
IEN-116 has nothing to do with the OS the DNS server is running on; it's got nothing to do with DNS at all. IEN-116 is a completely different protocol.

ghana

ASKER

Great job oBdA, thanks!

It's still strange why configuring IEN-116 seems to fix some name resolution problems. The only common thing I could find: IEN-116 used port 42-tcp and 42-upd. And WINS replication uses port 42-tcp. But it's the replication and not WINS NetBios over TCP/IP name service (port 137-upd). Could IEN-116 work as 'WINS alternative'??? I don't think so...

chad

Excellent info there oBda.
>>dates back to stone-age
I would have to say so. That text file that you linked is dated 1979 :-)

ghana

ASKER

> That text file that you linked is dated 1979 :-)
Yes. And I thought it was a joke when talking about ARPANET...

oBdA

I actually doubt that specifying the 005 option actually helps anything; never used it, never had problems in several surroundings. If on the specified server nothing listens on the port (not to mention actually listening to IEN-116), it simply can't have anything to do with name lookup problems. It's like an American standing on the North Pole trying to read a Russian text to a Japanese who's standing on the South Pole.
My guess is that the client(s) or the DHCP server had a hickup, and changing something (anything) cured it.

ghana

ASKER

Nice example oBdA. ;-) That's the most probably explanation. As already mentioned I've never used it too and also never had any problems.

Thanks again!