Why filename with weird chars can be created but not accessed via CIFS?

Question

I have a filesystem with some old files, which were probably copied there with some windows encoding in filenames (and not UTF8). When I try to backup them to samba share (Hetzner Storage Box) via CIFS-mounted filesystem, the files are created, but are not accessible in any way. The only way to remove them is via other means (like SFTP access to the share). I am using rdiff-backup, but the same happens with rsync or plain cp.

Original file:

-rwxr-xr-x 1 www-data www-data 2082 May 21  2010 ./domain/old/images/images2010/news/53x53_A?istýjrancejevonku.jpg

File on the samba share:

ls: '53x53_A?istýjrancejevonku.jpg': No such file or directory
total 48
-rwxr--r--  1 root root 2082 Nov 20 23:49 53x53_A?istýjrancejevonku.jpg

The share is mounted with unix/posix extensions, but needs vers=1.0 option in Debian 11 as otherwise it says unix extensions are not available on the server via SMB 3.1.1.

grep cifs /proc/mounts
//xxx.your-storagebox.de/backup /backups/xxx cifs rw,relatime,vers=1.0,cache=strict,username=xxx,uid=0,forceuid,gid=0,forcegid,addr=2a01:xxxx,soft,unix,posixpaths,serverino,mapposix,acl,noperm,rsize=1048576,wsize=65536,bsize=1048576,echo_interval=60,actimeo=1 0 0

Filenames with utf8 chars are working normally when copied to this share, just files with non-utf8 chars are problematic. Is there any mount option which can allow me to copy/backup these files? Or rdiff-backup option, which would workaround it (I guess not as the copy operation itself succeeds)?

Answer 1

(1) Workaround :

You can try this :

cd ./domain/old/images/images2010/news/
mv 53x53_*ancejevonku.jpg normal_name.jpg

Proceed with your workflow.
When required , you can rename that back to something like the original.

(2) Solution :

I am not very clear what your Issue is or what you want to achieve.
The way I am interpreting your Situation , this Solution will work :
On the Original Directory, top-level of the back-up , you can make a zip (or tar) file of the whole Directory.
Then back-up this zip (or tar) file to you cifs volume. The weird filename will then be hidden inside that container , hence the workflow will not encounter the Current Issue.
When necessary , you can unzip to the original Directory where the weird filename will come out to be visible , but there is no Access Issue on the workflow there.