[Samba] Problems related to error status_file_locking_conflict

[Robert W. Smith]

I am running two Fedora 13 servers, one as a Samba PDC and the other as
a BDC. For the past week I have been tracing a series of issues which
may or may not be related to Samba 3.5.4. Here is one problem that I am
tracking and need help from the list with suggestions.

>From a wireshark trace between my Samba server and an XP client I am
seeing the following error status returned for up to a minute for
certain files:

error: STATUS_FILE_LOCK_CONFLICT after a SMB Write AndX Request

Specifically, this is during the login process which now takes over a
minute due to these error messages. The files in question are related to
MS credentials in /Application
Data/Microsoft/CryptNetUrlCache/Content/<long string> and /Application
Data/Microsoft/CryptNetUrlCache/Metadata/<same long string>. After a
while we get an error that pops up in XP and says that the contents of
this file could not be saved. As an aside I have had the same message
occur for /History/index.dat and /Cookies/index.dat.

Running lsof during the login process I do see the files in questions
but the lsof output does not indicate that they are locked in any way as
shown next:

smbd    6884 <user>   36u   REG       0,22       24 60784737 <some
prefix>/Application Data/Microsoft/CryptnetUrlCache/Content/<long
string>

The [homes]  and [profiles] shares are stored on the BDC with an LDAP
slave backend. The PDC provides login services and the [netlogon] share
and the primary LDAP backend.

In the wireshark trace I see the following related to the
file /Application Data/Microsoft/CryptNetUrlCache/Content/<long string>:
1) the file  gets queried with a Trans2 Request, Query Path Info, Query
File Basic Info, and return Success
2) the file is created with NT Create AndX Request, with return Success
3) the file is queried again, Trans2 Request, Query File Info, Query
File Internal Info, with return Success
4) the file is written to with, Write Request, 0 bytes at offset 24,
with return Success
5) the file is written again with, Write AndX Request, 24 bytes at
offset 0, with return ERROR: STATUS_FILE_LOCK_CONFLICT
and this last Write Andx Request continues for up to a minute or longer.

As I mentioned all of our domain login times have increased
significantly and many other aspects of general computing and network
shares have slowed. My users are complaining and frustrated that I have
not resolved this issues. Where can I look on my Samba servers and
Linux/Fedora 13 specifically if I am having file and record locking
issues related to the XP clients. (note: my wife is one of the users and
she is about to fire me or worse... ;)

Any and all suggestions are welcome.

Bob Smith
BISLink Internet Services
Private Consultant
Great Falls, VA USA