More questions about WINS, interfaces, etc

[Luke Kenneth Casson Leighton]

On Thu, 18 Sep 1997 mac at nibsc.ac.uk wrote:

> Hi all,
> 
> >> I have yet another question about WINS and DNS...  Why can't the
> >> DNS be used as the database of reference for name-to-address
> >> mappings when using NB over TCP/IP?
> >
> >we're working on that, for samba-2.
> 
> 
> No, no, NO !!!

??  i don't understand.

ok.  i'll re-read (or, more like read) your question.  why can't dns be 
used as the database of reference for name-to-address mappings.

it can be.  put "dns proxy = yes" in the [global] section of smb.conf.  
this will do a gethostbyname() call on the NetBIOS name, and cache the 
response received for up to two hours.  this is because gethostbyname() 
is a blocking call, which therefore disrupts your name services and 
browsing services until gethostbyname() returns.

> Why can't I have completely separate DNS and NB namespaces?

i don't understand the intent behind your question.  DNS and NetBIOS 
namespaces are on 

> Windows clients support this quite happily, so why can't Samba?

no they don't: only NT workstation supports DNS resolution of ip 
addresses instead of using NetBIOS name resolution of ip addresses.

because of this limitation (in all windows clients to only use DNS, not 
NIS or NIS+, and in all windows clients except NT, which uses DNS 
directly), we have added an option "dns proxy = yes" which results in a 
gethostbyname() call if a NetBIOS name is not in the WINS cache in nmbd.

> Each system has its own repository of information (named, or WINS server)
> and distinct mechanisms exist for lookup and retrival of info.

true.  it is worth mentioning that the resolution of these names is on 
completely separate port numbers.  it is also worth mentioning that 
rfc1001/2.txt (NetBIOS) is based on rfc883.txt (DNS).

> By all means give Samba the capability to use the DNS as the prime source
> of information, but please, please allow it also to keep the NB namespace
> uterly separate.

we do.  DNS-looked-up names are marked with a special flag: "DNS" or 
"DNSFAIL" in the WINS cache.  if the NetBIOS name is subsequently 
registered (a pc gets switched on), then the DNS entry is deleted.

luke


Luke Kenneth Casson Leighton (lkcl at switchboard.net)
"Deal with difficult problems while they are still easy"