Hi everybody again,

Another couple of questions for you gurus

Which of the followìing is the correct (default) name resolution process in
win 2000/2003/XP?

a) DNS res first and Netbios res after (as I thought):

DNS Cache -> HOSTS file -> DNS query -> Netbios cache -> WINS query ->
Broadcast Netbios query - LMHOSTS

or

b) DNS res first and Netbios res after (as states in MOC 2276B for netbios
H-node type ):
Netbios cache -> NBNS (WINS) query -> Broadcast Netbios query - LMHOSTS ->
DNS Cache -> HOSTS file -> DNS query

Can the Netbios node type deal with the DNS name resolution process in any
way?
(In the PCs I installed I noticed that the node type was "Unknown" (0x0)
instead of Broadcast as It should be set as the default!)

Sadly, that doesn't make any sense to me!

thanks for any hints!

MD

"M D" <mdbl@NOSPAMinwind.it> ha scritto nel messaggio
news:%23YTVChq0GHA.720@TK2MSFTNGP02.phx.gbl...
> Hi everybody again,
>
> Another couple of questions for you gurus
>
> Which of the followìing is the correct (default) name resolution process
> in
> win 2000/2003/XP?
>
> a) DNS res first and Netbios res after (as I thought):
>
> DNS Cache -> HOSTS file -> DNS query -> Netbios cache -> WINS query ->
> Broadcast Netbios query - LMHOSTS
>
> or
>
> b) DNS res first and Netbios res after (as states in MOC 2276B for netbios
> H-node type ):
> Netbios cache -> NBNS (WINS) query -> Broadcast Netbios query - LMHOSTS ->
> DNS Cache -> HOSTS file -> DNS query
>
> Can the Netbios node type deal with the DNS name resolution process in any
> way?
> (In the PCs I installed I noticed that the node type was "Unknown" (0x0)
> instead of Broadcast as It should be set as the default!)
>
> Sadly, that doesn't make any sense to me!
>
> thanks for any hints!
>
> MD
>

In the book I'm studying windows networking it is written that DNS
resolution comes before NETBIOS resolution.
The only thing that could prevent this from happening is a misconfiguration
of DNS that would leave DNS aside & jump to NETBIOS resolution directly.
The thing that it is still not clear is the MOC 2276B statement about
resolution and the reference to the H netbios node type (how can the node
type rule the DNS resolution???)

Any comments?

Thanks


MD

"M D" <mdbl@NOSPAMinwind.it> wrote in message
news:Osr7Bbx0GHA.4924@TK2MSFTNGP05.phx.gbl...
>
> "M D" <mdbl@NOSPAMinwind.it> ha scritto nel messaggio
> news:%23YTVChq0GHA.720@TK2MSFTNGP02.phx.gbl...
>> Hi everybody again,
>>
>> Another couple of questions for you gurus
>>
>> Which of the followìing is the correct (default) name resolution process
>> in win 2000/2003/XP?
>>
>> a) DNS res first and Netbios res after (as I thought):

The question is either ill conceived or incomplete (and never
likely to be ask as such on a real exam).

The issue is which TOOL (client, program etc.) is being used.

Without knowing that you cannot know whether the query is
a "NetBIOS" resolution OR a "DNS" query.

Once you know that then EACH query may (usually) end up
trying both sets of methods, but each will start with it's own
methods: e.g., DNS will use DNS first, NetBIOS as backup
if all DNS methods fail.

>> DNS Cache -> HOSTS file -> DNS query -> Netbios cache -> WINS query ->
>> Broadcast Netbios query - LMHOSTS

You can never know the NetBIOS ORDER without knowing the client
"node type": B-node (broadcast), P-node (WINS client only), M-node
(b first, Wins request second), and H-node (WINS request, then broadcast.)


>> or
>>
>> b) DNS res first and Netbios res after (as states in MOC 2276B for
>> netbios
>> H-node type ):
>> Netbios cache -> NBNS (WINS) query -> Broadcast Netbios query -
>> LMHOSTS ->
>> DNS Cache -> HOSTS file -> DNS query
>>
>> Can the Netbios node type deal with the DNS name resolution process in
>> any
>> way?

It (all NetBIOS methods) might be used as a SUPPLEMENT to the
DNS methods if all DNS methods fail to return a positive answer.

This is the default but can be disabled in the registry.

NetBIOS resolution only uses DNS methods as a supplement IF
you check a box on the WINS tab of the IP config. (If you knew
your NetBIOS was setup correct AND that DNS could never
you would NOT want your machines going "out to the Internet DNS
servers" looking for INTERNAL names, thus the check box option.)

>> (In the PCs I installed I noticed that the node type was "Unknown" (0x0)
>> instead of Broadcast as It should be set as the default!)

Did you use DHCP to assign IP addresses?

If you do that and assign a WINS server address you MUST also assign
the NetBIOS node type (usually H-node which is code 0x08)

>> Sadly, that doesn't make any sense to me!

That because those sources are both incomplete and and in some sense
worrying about the wrong level of detail (for both the exam and real
life.)

>> thanks for any hints!
>>
>> MD
>>
>
> In the book I'm studying windows networking it is written that DNS
> resolution comes before NETBIOS resolution.

That book is too simplistic.

Tools like ping ALWAYS start with DNS name resolution.
Tools like Internet explorer MAY start with the NetBIOS name
if the name is formatted a certain way.) (Earlier versions did, but
I haven't checked lately for IE.)

> The only thing that could prevent this from happening is a
> misconfiguration of DNS that would leave DNS aside & jump to NETBIOS
> resolution directly.

No, that is a slight misconception. The client software DECIDES which
type of resolution is going to be tried, but the OS (name resolvers) decide
the order of that particular resolution AND whether the alternate mathods
will be used to supplment the resolution.

Does that make more sense?

[The original practice question was written by someone who doesn't
fully understand what is actually happening.]

> The thing that it is still not clear is the MOC 2276B statement about
> resolution and the reference to the H netbios node type (how can the node
> type rule the DNS resolution???)

It doesn't. It only rules the order of the "NetBIOS portion" of the
supplementary methods when DNS resolution is taking place but
not succeeding with "DNS methods", and thus fails through to the
NetBIOS methods.

Learn it this way:

Internet names and clients start with DNS, NetBIOS may be used
to supplment.

NetBIOS names and clients start with NetBIOS, but DNS methods
MAY be used (if checked) to supplement.

In either case the individual method sets will follow their own order.

DNS: Own name, hosts file (if any), DNS server (if available)
(plus NetBIOS methods)

NetBIOS: Cache*, "node type" stuff*, LMhosts file
(plus optional DNS methods)

*Node type stuff means what we discussed above for each node type,
whether Broadcast, WINS request, or both and in what order are used.

NetBIOS cache includes: names loaded explicitly in cache, own names
registered, and recently resolved names.

The only thing that might SEEM odd, is that LMHosts files are not
checked until AFTER your machine has potentially gone onto the
network TWICE (broadcasts and WINS request): This is due to
the ability of LMHOSTS entries to be #PRE preloaded into the
cache.

The idea is that IF you wanted it "checked first" you would have
#PRE loaded it -- and the dynamic methods will NORMALLY
override any old, out of date entries left in LMHOSTS files.

One of the issues with HOSTS files (and LMHOSTS to a lesser
extent) is that incorrect entries are USED once they are found and
therefore could override more accurate information that is at
the server (but not ever seen by the resolver.)

The order of the LMHOSTS file alleviates this issue for all but
those entries which are #PRE loaded.

Thing that always seems to confuse newcomers (but isn't covered
well in any text or on any exam) is that once a WRONG address
is 'resolved' the machine is stuck with that address, and that if
a DNS server is 'contacted' (even if it returns NO SUCH NAME)
then NO OTHER DNS server will be tried.

This latter appears as people trying to put "mixed DNS Server"
settings on their client NIC IP configuration thinking (incorrectly)
that the first will be tried, and if that server does not have the answer
then the other will be tried -- it won't.

Rule: All (internal) DNS clients must use STRICTLY the (internal)
DNS Server (set) which can resolve ALL of the names they will
ever need.


--
Herb Martin, MCSE, MVP
Accelerated MCSE
http://www.LearnQuick.Com
[phone number on web site]

Any comments?
>
> Thanks
>
>
> MD
>

Thanks Martin for your unexpected reply!
What you say really does make sense but I'm going to think about that later:
it's almost half past 2 in the morning right now

Thanks again

MD