[Samba] New Samba 4.22 and SMB3 Directory Leases

[Achim Gottinger]

Am 08.03.2025 um 13:40 schrieb miguel medalha via samba:
> I decided to try the recently released Samba 4.22. I installed it on a file
> server, with no changes to smb.conf.
>
> The new SMB3 Directory Leases function is enabled by default on a
> non-clustered system. In my case, it was therefore automatically enabled. I
> noticed the behavior I am about to describe.
>
> A directory on this server supports a timestamping service. Any document
> copied to that location by the Windows users gets renamed to a timestamp in
> the format "doc-YYYYMMDD-HHMMSS". One of the users contacted me, saying that
> the service was not working anymore, whereas in the previous day everything
> was fine. I made a test, copying a file to the dir. Contrary to the usual
> behavior, which almost immediately presented us with a renamed file, nothing
> seemed to be happening. After some time, the original file suddenly
> disappeared from Windows Explorer, leaving an apparently empty window. Even
> repeatedly refreshing the window manually by using F5 still showed it empty.
> Watching the process from the Linux side the renamed file was there as it
> should. Finally, after literally several *minutes*, the file appeared on the
> Explorer window. I made further testing and the same happened every time.
> Remembering that the only change overnight had been the new SMB3 Directory
> Leases, I edited the smb.conf file to include "smb3 directory leases = no".
> After reloading the Samba config, the files began to appear instantaneously
> on the Explorer window, as usual.
>
> Three question remain:
>
> Is this delay of minutes to be expected with "smb3 directory leases"?
>
> If so, which scenario does the function serve effectively, why and when
> would it be needed?
>
> Being new behavior, which can produce unexpected results, shouldn't the
> smb.conf default be "no" instead of "auto"? Shouldn't new behavior be
> specifically asked for?
>
> Thank you.
>
>
>
Hello,

I experience the delay as well. If I create an file on the linux server it takes a while till it appears on a windows client.
Seeme hitting F5 does alos not trigger an cache flush and reread of the dir. Turning of the smb3 directory leases" fixes that.

Achim~