samba - May 2023 - vfs_shadow_copy2 cannot read/find snapshots

On Tue, 2023-05-23 at 11:52 +0200, Sebastian Neustein via samba
wrote:
> Am 23.05.2023 um 10:27 schrieb Anoop C S:
> > On Mon, 2023-05-22 at 15:32 +0200, Sebastian Neustein via samba
> > wrote:
> > > log still says:
> > > [2023/05/22 15:23:23.324179,? 1]
> > > ../../source3/modules/vfs_shadow_copy2.c:2222(shadow_copy2_get_sh
> > > adow
> > > _copy_data)
> > > ??? shadow_copy2_get_shadow_copy_data: SMB_VFS_NEXT_OPEN failed
> > > for
> > > '/srv/glvol_samba/admin/projects/.snaps' - Permission
denied
> > > 
> > > I had it working before and had some trouble with these two
> > > parameters aswell.
> > 
> > Since you mentioned that it was working before, what changed now?
> > Is
> > that an update to GlusterFS or Samba that is causing the issue? Or
> > something else?
> 
> The only thing I am aware of is that I changed
> - mounting the device from /etc/fstab to 
> /etc/systemd/system/srv-glvol_samba.mount, which looks like this:
> - debian version changed from 11.6 to 11.7.
> - smb.conf to resolve this
Ok.

Initially I thought whether we missed any fixes on both sides(Samba
4.17.8 and GlusterFS 10.4). I looked at the patches and it looks like
everything needed are part of installed versions. I even tried to
reproduce(without acl_xattr) without any luck. This might have to do
with how FUSE mount is setup on the server.

Can you also please check whether you can list the contents of various
snapshots present under /srv/glvol_samba/admin/projects/.snaps from
server?
> > Can you check for any other errors in
> > /var/log/glusterfs/snaps/glvol_samba/snapd.log or in GlusterFS FUSE
> > mount log under /var/log/glusterfs/?
> 
> These are all log entries when I unmount and mount the volume:
> 
> root at B741:/var/log/glusterfs# cat glusterd.log
> The message "I [MSGID: 106496] [glusterd-
> handshake.c:954:__server_getspec] 0-management: Received
> mount request for volume shd/glvol_samba" repeated 19 times between 
> [2023-05-22 22:00:21.718887 +0000] and [2023-05-22 22:00:21.980543
> +0000] [2023-05-23 09:14:20.346930 +0000] I [MSGID: 106496] 
> [glusterd-handshake.c:954:__server_getspec] 0-management: Received
> mount request for volume /glvol_samba
In addition to that there will be a log file corresponding to the FUSE
mount of GlusterFS volume under /var/log/glusterfs with mount point as
log file name? Please check if there are any warning/error entries
while trying to list previous versions from windows.


Regards,
Anoop C S.

Hi Anoop

this might bring us closer!

Am 23.05.2023 um 19:35 schrieb Anoop C S:
>
> Can you also please check whether you can list the contents of various
> snapshots present under /srv/glvol_samba/admin/projects/.snaps from
> server?
I can see all? snapshots which are available on the gluster cluster. I 
can enter those directories and see and read all files I expect.
> In addition to that there will be a log file corresponding to the FUSE
> mount of GlusterFS volume under /var/log/glusterfs with mount point as
> log file name? Please check if there are any warning/error entries
> while trying to list previous versions from windows.
Yes, there is a file called; /var/log/glusterfs/srv-glvol_samba.log

When the error in samba occurs there are these entries:
[2023-05-24 12:30:09.764077 +0000] I [MSGID: 139001] 
[posix-acl.c:252:posix_acl_log_permit_denied] 0-posix-acl-autoload: 
client: -, gfid: 08ee40ea-8f84-4240-a6b1-e56e0d393016, 
req(uid:1001103,gid:1000513,perm:4,ngrps:20), 
ctx(uid:0,gid:0,in-groups:0,perm:000,updated-fop:INVALID, acl:-) [Keine 
Berechtigung]
[2023-05-24 12:30:09.764234 +0000] W [fuse-bridge.c:1642:fuse_fd_cbk] 
0-glusterfs-fuse: 201346: OPENDIR() /admin/projects/.snaps => -1 (Keine 
Berechtigung)

This looks like we are getting closer!

And you are right, you asked what has changed. And in the back of my 
head it rings a bell. I might have added vfs_glusterfs_fuse later on. So 
probably I used the mount point directly when it was working. But 
removing the vfs module does not heal the situation.

I am really thankful for all your effort you are putting in this!

Regards
Sebastian