[PATCH 34/71] cifs: Set default Netbios RFC1001 server name to hostname in UNC

[PATCH 34/71] cifs: Set default Netbios RFC1001 server name to hostname in UNC

[Steve French]

>Windows SMB servers (including SMB2+) which are working over RFC1001
>require that Netbios server name specified in RFC1001 Session Request
>packet is same as the UNC host name. Netbios server name can be already
>specified manually via -o servern= option.
>With this change the RFC1001 server name is set automatically by extracting
>the hostname from the mount source.
>
> Signed-off-by: Pali Rohár <pali@kernel.org>

Pali,
Is there a good way to simulate this with SMB2.1 or SMB3+ mount to Windows?

-- 
Thanks,

Steve

Re: [PATCH 34/71] cifs: Set default Netbios RFC1001 server name to hostname in UNC

[Pali Rohár]

On Sunday 19 January 2025 19:38:23 Steve French wrote:
> >Windows SMB servers (including SMB2+) which are working over RFC1001
> >require that Netbios server name specified in RFC1001 Session Request
> >packet is same as the UNC host name. Netbios server name can be already
> >specified manually via -o servern= option.
> >With this change the RFC1001 server name is set automatically by extracting
> >the hostname from the mount source.
> >
> > Signed-off-by: Pali Rohár <pali@kernel.org>
> 
> Pali,
> Is there a good way to simulate this with SMB2.1 or SMB3+ mount to Windows?
> 
> -- 
> Thanks,
> 
> Steve

Sure, it is very easy. Just call standard mount with -o port=139 option.
For example:

mount //hostname/share /mnt/smb -t cifs -o vers=3.1.1,port=139

And you can watch network traffic in wireshark.

Just to note that for SMB 3.1.1 it is currently broken and other patches
in this series are fixing it:
https://lore.kernel.org/linux-cifs/20241222163050.24359-1-pali@kernel.org/t/#u

Your mentioned change "cifs: Set default Netbios RFC1001 server name to
hostname in UNC" is the last one in that patch series.