samba - Oct 2017 - Share mounts in SMBv1 mode, but fails weirdly in SMBv2 mode

Hi,

We're slowly deprecating SMBv1 support at work, so I'm trying to mount 
our Samba network shares using SMBv2.0. This should in principle be 
supported by the server, and seems works well enough for the Windows 
clients. But it fails for me with some errors which I do not understand.

Can you help me figure out what's going on? Here's my system 
configuration and a quick summary of what I have so far:

hadrien at linux-2ak3:~> uname -a
Linux linux-2ak3 4.13.5-1-default #1 SMP PREEMPT Thu Oct 5 18:28:26 UTC 
2017 (3fd9659) x86_64 x86_64 x86_64 GNU/Linux
hadrien at linux-2ak3:~> /sbin/mount.cifs --version
mount.cifs version: 6.5
hadrien at linux-2ak3:~> sudo mount -v -t cifs //nfsserv22/expsi test -o 
credentials=<path to credentials file>,vers=2.0
domain=LAL
mount.cifs kernel mount options: 
ip=134.158.91.155,unc=\\nfsserv22\expsi,vers=2.0,user=grasland,,domain=LAL,pass=********
mount error(95): Operation not supported
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)
hadrien at linux-2ak3:~> dmesg | tail
[...]
[13424.783242] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-2
[13424.789504] CIFS VFS: cifs_read_super: get root inode failed

Replacing "vers=2.0" with "vers=1.0" in the mount command
line makes
this work, so I'm quite confident that my general configuration is 
correct and the problem is somehow specific to the SMBv2 protocol. 
However, I'm a Samba newbie and would welcome any tips on how to extract 
more information from this machine/server in order to figure out why 
SMBv2 specifically is failing.

Thanks in advance for your help,
Hadrien Grasland

On Thu, Oct 12, 2017 at 03:58:58PM +0200, Hadrien Grasland via samba
wrote:
> Hi,
> 
> We're slowly deprecating SMBv1 support at work, so I'm trying to
> mount our Samba network shares using SMBv2.0. This should in
> principle be supported by the server, and seems works well enough
> for the Windows clients. But it fails for me with some errors which
> I do not understand.
> 
> Can you help me figure out what's going on? Here's my system
> configuration and a quick summary of what I have so far:
> 
> hadrien at linux-2ak3:~> uname -a
> Linux linux-2ak3 4.13.5-1-default #1 SMP PREEMPT Thu Oct 5 18:28:26
> UTC 2017 (3fd9659) x86_64 x86_64 x86_64 GNU/Linux
> hadrien at linux-2ak3:~> /sbin/mount.cifs --version
> mount.cifs version: 6.5
> hadrien at linux-2ak3:~> sudo mount -v -t cifs //nfsserv22/expsi test
> -o credentials=<path to credentials file>,vers=2.0
> domain=LAL
> mount.cifs kernel mount options:
ip=134.158.91.155,unc=\\nfsserv22\expsi,vers=2.0,user=grasland,,domain=LAL,pass=********
> mount error(95): Operation not supported
> Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)
> hadrien at linux-2ak3:~> dmesg | tail
> [...]
> [13424.783242] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-2
> [13424.789504] CIFS VFS: cifs_read_super: get root inode failed
> 
> Replacing "vers=2.0" with "vers=1.0" in the mount
command line makes
> this work, so I'm quite confident that my general configuration is
> correct and the problem is somehow specific to the SMBv2 protocol.
> However, I'm a Samba newbie and would welcome any tips on how to
> extract more information from this machine/server in order to figure
> out why SMBv2 specifically is failing.
Can you get a wireshark trace on port 445 between client and
server ? That would help.

Le 13/10/2017 à 01:46, Jeremy Allison via samba a
écrit :
> On Thu, Oct 12, 2017 at 03:58:58PM +0200, Hadrien Grasland via samba wrote:
>> Hi,
>>
>> We're slowly deprecating SMBv1 support at work, so I'm trying
to
>> mount our Samba network shares using SMBv2.0. This should in
>> principle be supported by the server, and seems works well enough
>> for the Windows clients. But it fails for me with some errors which
>> I do not understand.
>>
>> Can you help me figure out what's going on? Here's my system
>> configuration and a quick summary of what I have so far:
>>
>> hadrien at linux-2ak3:~> uname -a
>> Linux linux-2ak3 4.13.5-1-default #1 SMP PREEMPT Thu Oct 5 18:28:26
>> UTC 2017 (3fd9659) x86_64 x86_64 x86_64 GNU/Linux
>> hadrien at linux-2ak3:~> /sbin/mount.cifs --version
>> mount.cifs version: 6.5
>> hadrien at linux-2ak3:~> sudo mount -v -t cifs //nfsserv22/expsi
test
>> -o credentials=<path to credentials file>,vers=2.0
>> domain=LAL
>> mount.cifs kernel mount options:
ip=134.158.91.155,unc=\\nfsserv22\expsi,vers=2.0,user=grasland,,domain=LAL,pass=********
>> mount error(95): Operation not supported
>> Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)
>> hadrien at linux-2ak3:~> dmesg | tail
>> [...]
>> [13424.783242] CIFS VFS: ioctl error in smb2_get_dfs_refer rc=-2
>> [13424.789504] CIFS VFS: cifs_read_super: get root inode failed
>>
>> Replacing "vers=2.0" with "vers=1.0" in the mount
command line makes
>> this work, so I'm quite confident that my general configuration is
>> correct and the problem is somehow specific to the SMBv2 protocol.
>> However, I'm a Samba newbie and would welcome any tips on how to
>> extract more information from this machine/server in order to figure
>> out why SMBv2 specifically is failing.
> Can you get a wireshark trace on port 445 between client and
> server ? That would help.
>
There you go. I attached it to the e-mail, not sure if that's the proper 
way to send (small) files around on this list, if not please tell me :)