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Windows PC DNS Lookups Slow?

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The Question is:

Dear Wizard,
I am working at a client site using an Alpha running OpenVMS V7.1, UCX V4.2.
I noticed that the NAME_SERVICE in UCX was set incorrectly as a UCX SHOW HOST
 produced an error after the list of local hosts had been displayed. So I set
 it using.....
UCX> set name /server=(name1,name2) /system /enable -
 /transport=tcp /domain="<name-here>.com"
And then....
Showed loads of remote hosts and did not produce any errors.
However, there has been one side-effect. The customer uses the terminal
 emulation package SmarTerm to connect from their PC's to the Alpha. When name
 server was incorrect, the initiation of a connection from the PC to the Alpha
 using SmarTerm or telnet fr
om the DOS prompt was immediate.
Since I made the change there is now a 30 second or so delay between invoking
 SmarTerm and getting the Username prompt from the Alpha. Once a connection has
 been established, response is normal. A ping from the PC DOS prompt to the
 Alpha shows a delay tim
e of only 1mS.
I can telnet from other VMS nodes using both the i/p name and the i/p address
 and the initiation of a connection is immediate.
I did a....
UCX> set name /noserver=(name1,name2) /system
and the initiation of a connection from SmarTerm and telnet from the PC's was
 then immediate, as it was when the name server was incorrect. I set the name
 server correctly again and the delay re-appeared.
What would be the cause for the delay when the correct name server is used? Is
 the delay caused by UCX checking for rejected hosts?

The Answer is :

  Please contact a PC wizard and find out what the PC is doing.
  You may/will need to perform some level of packet tracing, to
  see what the PC is doing.  (This is probably a DNS-based lookup
  timing out somewhere.)
  Please move to supported OpenVMS Alpha and TCP/IP Services
  versions, and please apply the ECOs for the installed kits.

answer written or last revised on ( 6-FEB-2002 )

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