[Samba] Samba 4 - ISO-8859-15 filenames not listed while browsing

[Ali SIMON]

 Hello,

I have an issue with a german application that generates files with
iso-8859-15 encoded filenames.

I have 2 Linux Suse servers, both connected to the same NAS filesystem, and
sharing it via Samba.

"unix charset" in smb.conf set to default utf-8
LC_CTYPE & LANG locale are set to en_US.UTF-8


- First server is Samba-3.6.3 (SLES11 SP4, kernel 3.0.101-107-default) :
those files are accessible from windows/smbclient, with UCS2 characters (ie
"\344" for "ä") being replaced with a "_"

- Second one is Samba-4.6.9 (SLES12 SP2, kernel 4.4.103-6.38-default) :
those files simply don't show up while browsing.


In any case, log.smdb complains about :
convert_string_internal: Conversion error: Illegal multibyte sequence

If I change the  "unix charset = iso-8859-15" in the config for Samba4, it
shows the file while browsing, but then users are reporting that access is
now very slow (bench method is by compiling a program whose sources are on
the share).

I've tried various things already, but to no avail.

Any ideas or help is much appreciated.
Regards