Single label DNS

[Roger Beall]

Based on service pack 4 and Q300684 workaround for single
label domain names, the following question arises: Does
microsoft intend to support single label domain names in
the future or should one plan to remove the single label
domain and rebuild it following dns rfc guidance? Several
customers have the single label domain and while the
workaround of Q300684 works, they are wondering if this
will be an issue in future service packs.

 

[Danny Sanders]

I'm not from MS but my take is they are moving away from supporting single
label domain names. In NT 4.0 it was perfectly acceptable to have a single
label domain name. In Win 2k it is "strongly recommended" to use a domain
name that follows the DNS rfcs. They provide a "workaround" for those that
don't.

I would not think they would take a step backwards now.

hth
DDS W 2k MVP MCSE

 

[Alan Wood [MSFT]]

Hi Roger,
We really would preffer to use FQDN over Single labled. There are
alot of other issues that you can run into when using a Single labeled
domain name with other AD integrated products. Exchange would be a great
example. Also note that the DNR (DNS RESOLVER) was and is designed to
Devolve DNS requests to the LAST 2 names.

Example: Single Labeled domain .domainA
then, you add additional domains on the forest.
child1.domainA
Child2.child1.domainA

If a client in the domain Child2 wants to resolve a name in domainA
Example. Host.DomainA and uses the following to connect to a share
\\host then it is not going to resolve. WHY, because the resolver is
first going to query for first for Host.Child2.child1.domainA, then it
next try HOST.Child1.domainA at that point the Devolution process is
DONE. We only go to the LAST 2 Domain Names.

Also note that if you have a single labeled domain name it causes excess
DNS traffic on the ROOT HINTS servers and being all Good Internet Community
users we definitely do not want to do that. NOTE that in Windows 2003,
you get a big Pop UP Error Message when trying to create a single labeled
name telling you DON'T DO IT. It will still allow you to do it, but you
will still be required to make the registry changes, which is really not
fun.

Microsoft is seriously asking you to NOT do this. We will support you but
it the end results could be limiting as an end results depending on the
services you are using.


Thank you,

Alan Wood[MSFT]

This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Ace Fekay [MVP]]

In

Hi Roger,
We really would preffer to use FQDN over Single labled. There
are alot of other issues that you can run into when using a Single
labeled domain name with other AD integrated products. Exchange
would be a great example. Also note that the DNR (DNS RESOLVER) was
and is designed to Devolve DNS requests to the LAST 2 names.

Example: Single Labeled domain .domainA
then, you add additional domains on the forest.
child1.domainA
Child2.child1.domainA

If a client in the domain Child2 wants to resolve a name in domainA
Example. Host.DomainA and uses the following to connect to a share
\\host then it is not going to resolve. WHY, because the
resolver is first going to query for first for
Host.Child2.child1.domainA, then it next try HOST.Child1.domainA
at that point the Devolution process is DONE. We only go to the
LAST 2 Domain Names.

Also note that if you have a single labeled domain name it causes
excess DNS traffic on the ROOT HINTS servers and being all Good
Internet Community users we definitely do not want to do that. NOTE
that in Windows 2003, you get a big Pop UP Error Message when trying
to create a single labeled name telling you DON'T DO IT. It will
still allow you to do it, but you will still be required to make the
registry changes, which is really not fun.

Microsoft is seriously asking you to NOT do this. We will support
you but it the end results could be limiting as an end results
depending on the services you are using.


Thank you,

Alan Wood[MSFT]

This posting is provided "AS IS" with no warranties, and confers no
rights.

Hi Alan,

Great explanation.

Would you mind if we save your post here and repost this in the future for
others' questions on single label names?

Thanks

--
Regards,
Ace

Please direct all replies to the newsgroup so all can benefit.
This posting is provided "AS IS" with no warranties.

Ace Fekay, MCSE 2000, MCSE+I, MCSA, MCT, MVP
Microsoft Windows MVP - Active Directory