[Samba] File locking problem

[Jeremy Allison]

On Wed, Mar 23, 2005 at 08:38:59PM +0100, Ulrik Guenther wrote:
> Hello everyone,
> 
> I have a 50-client Samba installation here (version of Samba is 3.0.12). The problem is, that files are not locked correctly. The scenario is the following:
> 1. User A opens a word document file and edits it
> 2. User B tries to open the same file, too
> 3. Instead of getting a warning that the file is in use by another user (like it was when we had NT4), Word opens the file without any problems
> 4. Now, both users edit the file and save it.
> 5. Result: Data loss.
> 
> This was just an example, the same thing occurs with AutoCAD files, Excel files, OpenOffice.org files,... every file, to sum it up.
> I already tried turning opportunistic locking off, turning strict locking on/off, nothing worked (you can find the smb.conf of the server attached to this mail). Last weekend I noticed a strange behavior: I was logged in on two clients with the same user and tried to open the same file on both. This time, the program (tried with Notepad, Word) protested and said that the file is already open.
> If I understood the functionality of Samba right, a new smbd process is spawned for every client who logs on (for every user or for every client?)... so might this be an issue with SystemV IPC?
> On this server we use LDAP for storing group and user information for Samba. The following data might also be valuable:
> * the server is empowered by an AMD Opteron 144 with 1 GiB of RAM
> * the operating system is FreeBSD 5.3-STABLE
> * Samba version is 3.0.12
> * OpenLDAP version is 2.2.23
> * OpenLDAP is running on the same computer as Samba
> * the data is stored on a Geom-Vinum RAID-1 volume set (mirrored)
> 
> Please, please help as soon as possible, as we already have lost a big bunch of data! If you need more information, just ask, I'll try to provide it asap.

This is strange - I don't see this with the current code, I don't
think too many others are either (there are people reporting issues
with Excel, but nothing this generic).

Try getting a debug level 10 log from two clients opening the same
file simultaneously.

Jeremy.