samba - Jun 2020 - Issues with FLOCK on NFS Share

Hello,

We are using Samba 4.10.16 as a readonly file server on a linux box with SLES
12. All is working fine with our NAS NFS Shares. We are now trying to integrate
new NFS Shares from an archive provider. We have some problems with samba not
responding, when accessing files on these archive NFS shares.
We have done some Samba-Debugging and found out, that the call to flock in
source3/lib/system.c (kernel_flock) do not return and is blocking samba!
Is it necessary to use file locking when using Samba as fileserver for readonly
access with NFS shares?
Can I disable locking with
#define HAVE_KERNEL_SHARE_MODES 0
in config.h.
What are the consequences?

Kind regards

Georg

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Howdy!

Am 6/30/20 um 2:37 PM schrieb Georg.Biberger--- via
samba:
> We are using Samba 4.10.16 as a readonly file server on a linux box with
SLES 12. All is working fine with our NAS NFS Shares. We are now trying to
integrate new NFS Shares from an archive provider. We have some problems with
samba not responding, when accessing files on these archive NFS shares.
> We have done some Samba-Debugging and found out, that the call to flock in
source3/lib/system.c (kernel_flock) do not return and is blocking samba!
kernel oplocks = no
> Is it necessary to use file locking when using Samba as fileserver for
readonly access with NFS shares?
Probably not.

-slow

-- 
Ralph Boehme, Samba Team                https://samba.org/
Samba Developer, SerNet GmbH   https://sernet.de/en/samba/
GPG-Fingerprint   FAE2C6088A24252051C559E4AA1E9B7126399E46

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On 30/06/2020 14:55, Ralph Boehme via samba wrote:
> Howdy!
>
> Am 6/30/20 um 2:37 PM schrieb Georg.Biberger--- via samba:
>> We are using Samba 4.10.16 as a readonly file server on a linux box
with SLES 12. All is working fine with our NAS NFS Shares. We are now trying to
integrate new NFS Shares from an archive provider. We have some problems with
samba not responding, when accessing files on these archive NFS shares.
>> We have done some Samba-Debugging and found out, that the call to flock
in source3/lib/system.c (kernel_flock) do not return and is blocking samba!
> kernel oplocks = no
Only problem with that, it is the default setting :-(

Can we see your smb.conf ?

Rowland