[cifs-protocol] Question about MS DNS server dropping packets from client

Hongwei Sun hongweis at microsoft.com
Thu Sep 29 12:46:15 MDT 2011

Hi, Kai,

   Just confirming what we already discussed in lab.   This is an known behavior to Windows DNS server.   Windows DNS server will suppress sending  responses  for  DNS  queries with format error (DNS_RCODE_FORMERR ) if there is a same error encountered in the last 60 seconds.   You can disable the suppression of the bad response using the registry key documented in the following KB  http://support.microsoft.com/kb/837928

  Please let me know if the setting works for you and if you have more questions.



-----Original Message-----
From: Kai Blin [mailto:kai at samba.org] 
Sent: Wednesday, September 28, 2011 11:52 PM
To: Interoperability Documentation Help; pfif at tridgell.net; cifs-protocol at samba.org
Subject: Question about MS DNS server dropping packets from client

Hash: SHA1

Hi folks,

While trying to test corner cases of the DNS implementation of Microsoft, I've noticed that if I send DNS packets that cause FORMERROR return values, the DNS server will silently drop further packets that would trigger a FORMERROR. I can still send and get replies to valid packets from the machine that is blocked for FORMERROR packets. If I wait a couple of minutes or restart the DNS server service, I can get one reply for a FORMERROR packet again, then I'm blocked again.

What's going on there, and more importantly, is there something I can do to turn this of?


- --
Kai Blin
Worldforge developer http://www.worldforge.org/ Wine developer http://wiki.winehq.org/KaiBlin Samba team member http://www.samba.org/samba/team/ -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.10 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/


More information about the cifs-protocol mailing list