Dank der aufschlussreichen Diskussion unter https://ubuntuforums.org/showthread.php?t=2375075 konnte ich es schließlich zum Laufen bringen. In meinem Fall wurde der folgende Fehler gemeldet
satyadeep@satyadeep:~$ sudo mount -a
[sudo] password for satyadeep:
mount error(22): Invalid argument
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)
Ich habe Folgendes in kern.log überwacht und gesehen
11:09 $ tail -f /var/log/kern.log
Mar 1 10:06:51 satyadeep kernel: [160456.442423] input: USB Optical Mouse as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/0003:0461:4D81.0003/input/input13
Mar 1 10:06:51 satyadeep kernel: [160456.442670] hid-generic 0003:0461:4D81.0003: input,hidraw0: USB HID v1.11 Mouse [USB Optical Mouse] on usb-0000:00:1d.0-1.2/input0
Mar 1 10:30:33 satyadeep kernel: [161879.205573] No dialect specified on mount. Default has changed to a more secure dialect, SMB2.1 or later (e.g. SMB3), from CIFS (SMB1). To use the less secure SMB1 dialect to access old servers which do not support SMB3 (or SMB2.1) specify vers=1.0 on mount.
Mar 1 10:30:33 satyadeep kernel: [161879.206637] CIFS VFS: Unable to select appropriate authentication method!
Mar 1 10:30:33 satyadeep kernel: [161879.206640] CIFS VFS: Send error in SessSetup = -22
Mar 1 10:30:33 satyadeep kernel: [161879.206658] CIFS VFS: cifs_mount failed w/return code = -22
Mar 1 10:48:22 satyadeep kernel: [162948.218284] No dialect specified on mount. Default has changed to a more secure dialect, SMB2.1 or later (e.g. SMB3), from CIFS (SMB1). To use the less secure SMB1 dialect to access old servers which do not support SMB3 (or SMB2.1) specify vers=1.0 on mount.
Mar 1 10:48:22 satyadeep kernel: [162948.219378] CIFS VFS: Unable to select appropriate authentication method!
Mar 1 10:48:22 satyadeep kernel: [162948.219382] CIFS VFS: Send error in SessSetup = -22
Mar 1 10:48:22 satyadeep kernel: [162948.219408] CIFS VFS: cifs_mount failed w/return code = -22
Wie angegeben, habe ich fstab wie folgt geändert:
//QQQ/share/sdm /mnt/store cifs username=XXX,password=YYY,domain=ZZZ,iocharset=utf8,sec=ntlm,vers=1.0 0 0
Beachten Sie das extra
vers = 1,0
Parameter. Danach habe ich getan
satyadeep@satyadeep:~$ sudo mount -a
Und es hat wie Charme funktioniert!