Problème de permission avec un périphérique RAID1

Je rencontre des problèmes avec un serveur domestique (Ubuntu 20.04.3) que j'ai installé.

Ma configuration : 1 Software RAID1 (mdadm) qui est monté via fstab sur /media/altocasa/NetDisk1

J'ai également activé un partage samba pour partager un dossier sur ce disque. Les autres dossiers sur le disque sont dédiés à divers services : -owncloud -transmission -Calibre -kodi

Mon problème concerne... les autorisations ! En effet, même si j'ai réussi à monter le dossier avec un groupe "data" contenant tous les utilisateurs qui ont besoin de R/W sur ce disque, et même si les permissions sont réglées sur drwxrwxrwx, tous les services que j'essaie d'utiliser signalent qu'ils n'ont pas les permissions suffisantes pour écrire sur un dossier du disque.

Mon mdadm.conf

# mdadm.conf
#
# Please refer to mdadm.conf(5) for information about this file.
#

# by default (built-in), scan all partitions (/proc/partitions) and all
# containers for MD superblocks. alternatively, specify devices to scan, using
# wildcards if desired.
#DEVICE partitions containers

# auto-create devices with Debian standard permissions
CREATE owner=root group=disk mode=0777 auto=yes

# automatically tag new arrays as belonging to the local system
HOMEHOST <system>

# instruct the monitoring daemon where to send mail alerts
MAILADDR admin@basat.org

# definitions of existing MD arrays

# This file was auto-generated on Wed, 02 Nov 2016 00:28:16 +0100
# by mkconf $Id$

ARRAY /dev/md0 metadata=1.2 spares=1 name=altocasa.alto:0 UUID=abf104eb:c48a9898:e19f5e29:b810dc85

Mon fstab

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/mmcblk0p2 during installation
UUID=0051b1ea-f028-4e24-852e-60f0e14deba5 /               ext4    errors=remount-ro 0       1
# /boot/efi was on /dev/mmcblk0p1 during installation
UUID=3AC6-9820  /boot/efi       vfat    umask=0077      0       1
/swapfile                                 none            swap    sw              0       0
#raid mount point /dev/md0
#UUID=abf104eb:c48a9898:e19f5e29:b810dc85 /media/altocasa/NetDisk1 auto nosuid,nodev,nofail,silent,permissions,x-gvfs-show umask=000,utf8 0 0
#UUID=1EFCAB415200A4AB  /media/altocasa/NetDisk1 auto nosuid,nodev,users,nofail,x-gvfs-show,uid=1000,gid=1001 0 0
#UUID=abf104eb:c48a9898:e19f5e29:b810dc85  /media/altocasa/NetDisk1 auto nosuid,rw,nodev,nofail,x-gvfs-show,users,uid=1000,gid=1001,permissions,utf8 0 0
/dev/md0  /media/altocasa/NetDisk1 auto nosuid,rw,nodev,nofail,x-gvfs-show,users,uid=1000,gid=1001,permissions,utf8 0 0

Mon Fichier de configuration Samba

#
# Sample configuration file for the Samba suite for Debian GNU/Linux.
#
#
# This is the main Samba configuration file. You should read the
# smb.conf(5) manual page in order to understand the options listed
# here. Samba has a huge number of configurable options most of which 
# are not shown in this example
#
# Some options that are often worth tuning have been included as
# commented-out examples in this file.
#  - When such options are commented with ";", the proposed setting
#    differs from the default Samba behaviour
#  - When commented with "#", the proposed setting is the default
#    behaviour of Samba but the option is considered important
#    enough to be mentioned here
#
# NOTE: Whenever you modify this file you should run the command
# "testparm" to check that you have not made any basic syntactic 
# errors. 

#======================= Global Settings =======================

[global]
    map to guest = bad user
    workgroup = workgroup
    logging = file
    netbios aliases = altoserver,altocasa
    socket options = TCP_NODELAY IPTOS_LOWDELAY SO_SNDBUF=131072 SO_RCVBUF=131072
    netbios name = AltoServer
    log file = /var/log/samba/log.%m
    passwd program = /usr/bin/passwd %u
    passdb backend = tdbsam
    default = NetDisk1
    obey pam restrictions = yes
    panic action = /usr/share/samba/panic-action %d
    os level = 20
    auto services = NetDisk1
    max log size = 1000
    server role = standalone server
    passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* .
    usershare allow guests = yes
    unix password sync = yes
    pam password change = yes
    server string = %h server (Samba, Ubuntu)

## Browsing/Identification ###

# Change this to the workgroup/NT-domain name your Samba server will part of

# server string is the equivalent of the NT Description field

#### Networking ####

# The specific set of interfaces / networks to bind to
# This can be either the interface name or an IP address/netmask;
# interface names are normally preferred
;   interfaces = 127.0.0.0/8 eth0

# Only bind to the named interfaces and/or networks; you must use the
# 'interfaces' option above to use this.
# It is recommended that you enable this feature if your Samba machine is
# not protected by a firewall or is a firewall itself.  However, this
# option cannot handle dynamic or non-broadcast interfaces correctly.
;   bind interfaces only = yes

#### Debugging/Accounting ####

# This tells Samba to use a separate log file for each machine
# that connects

# Cap the size of the individual log files (in KiB).

# We want Samba to only log to /var/log/samba/log.{smbd,nmbd}.
# Append syslog@1 if you want important messages to be sent to syslog too.

# Do something sensible when Samba crashes: mail the admin a backtrace

####### Authentication #######

# Server role. Defines in which mode Samba will operate. Possible
# values are "standalone server", "member server", "classic primary
# domain controller", "classic backup domain controller", "active
# directory domain controller". 
#
# Most people will want "standalone server" or "member server".
# Running as "active directory domain controller" will require first
# running "samba-tool domain provision" to wipe databases and create a
# new domain.

# This boolean parameter controls whether Samba attempts to sync the Unix
# password with the SMB password when the encrypted SMB password in the
# passdb is changed.

# For Unix password sync to work on a Debian GNU/Linux system, the following
# parameters must be set (thanks to Ian Kahan <<kahan@informatik.tu-muenchen.de> for
# sending the correct chat script for the passwd program in Debian Sarge).

# This boolean controls whether PAM will be used for password changes
# when requested by an SMB client instead of the program listed in
# 'passwd program'. The default is 'no'.

# This option controls how unsuccessful authentication attempts are mapped
# to anonymous connections

########## Domains ###########

#
# The following settings only takes effect if 'server role = primary
# classic domain controller', 'server role = backup domain controller'
# or 'domain logons' is set 
#

# It specifies the location of the user's
# profile directory from the client point of view) The following
# required a [profiles] share to be setup on the samba server (see
# below)
;   logon path = \\%N\profiles\%U
# Another common choice is storing the profile in the user's home directory
# (this is Samba's default)
#   logon path = \\%N\%U\profile

# The following setting only takes effect if 'domain logons' is set
# It specifies the location of a user's home directory (from the client
# point of view)
;   logon drive = H:
#   logon home = \\%N\%U

# The following setting only takes effect if 'domain logons' is set
# It specifies the script to run during logon. The script must be stored
# in the [netlogon] share
# NOTE: Must be store in 'DOS' file format convention
;   logon script = logon.cmd

# This allows Unix users to be created on the domain controller via the SAMR
# RPC pipe.  The example command creates a user account with a disabled Unix
# password; please adapt to your needs
; add user script = /usr/sbin/adduser --quiet --disabled-password --gecos "" %u

# This allows machine accounts to be created on the domain controller via the 
# SAMR RPC pipe.  
# The following assumes a "machines" group exists on the system
; add machine script  = /usr/sbin/useradd -g machines -c "%u machine account" -d /var/lib/samba -s /bin/false %u

# This allows Unix groups to be created on the domain controller via the SAMR
# RPC pipe.  
; add group script = /usr/sbin/addgroup --force-badname %g

############ Misc ############

# Using the following line enables you to customise your configuration
# on a per machine basis. The %m gets replaced with the netbios name
# of the machine that is connecting
;   include = /home/samba/etc/smb.conf.%m

# Some defaults for winbind (make sure you're not using the ranges
# for something else.)
;   idmap config * :              backend = tdb
;   idmap config * :              range   = 3000-7999
;   idmap config YOURDOMAINHERE : backend = tdb
;   idmap config YOURDOMAINHERE : range   = 100000-999999
;   template shell = /bin/bash

# Setup usershare options to enable non-root users to share folders
# with the net usershare command.

# Maximum number of usershare. 0 means that usershare is disabled.
#   usershare max shares = 100

# Allow users who've been granted usershare privileges to create
# public shares, not just authenticated ones

#======================= Share Definitions =======================

# Un-comment the following (and tweak the other settings below to suit)
# to enable the default home directory shares. This will share each
# user's home directory as \\server\username
;[homes]
;   comment = Home Directories
;   browseable = no

# By default, the home directories are exported read-only. Change the
# next parameter to 'no' if you want to be able to write to them.
;   read only = yes

# File creation mask is set to 0700 for security reasons. If you want to
# create files with group=rw permissions, set next parameter to 0775.
;   create mask = 0700

# Directory creation mask is set to 0700 for security reasons. If you want to
# create dirs. with group=rw permissions, set next parameter to 0775.
;   directory mask = 0700

# By default, \\server\username shares can be connected to by anyone
# with access to the samba server.
# Un-comment the following parameter to make sure that only "username"
# can connect to \\server\username
# This might need tweaking when using external authentication schemes
;   valid users = %S

# Un-comment the following and create the netlogon directory for Domain Logons
# (you need to configure Samba to act as a domain controller too.)
;[netlogon]
;   comment = Network Logon Service
;   path = /home/samba/netlogon
;   guest ok = yes
;   read only = yes

# Un-comment the following and create the profiles directory to store
# users profiles (see the "logon path" option above)
# (you need to configure Samba to act as a domain controller too.)
# The path below should be writable by all users so that their
# profile directory may be created the first time they log on
;[profiles]
;   comment = Users profiles
;   path = /home/samba/profiles
;   guest ok = no
;   browseable = no
;   create mask = 0600
;   directory mask = 0700

#[printers]
#   comment = All Printers
#   browseable = no
#   path = /var/spool/samba
#   printable = yes
#   guest ok = no
#   read only = yes
#   create mask = 0700

# Windows clients look for this share name as a source of downloadable
# printer drivers
#[print$]
#   comment = Printer Drivers
#   path = /var/lib/samba/printers
#   browseable = yes
#   read only = yes
#   guest ok = no
# Uncomment to allow remote administration of Windows print drivers.
# You may need to replace 'lpadmin' with the name of the group your
# admin users are members of.
# Please note that you also need to set appropriate Unix permissions
# to the drivers directory for these users to have write rights in it
;   write list = root, @lpadmin

[Share]
    path = /media/altocasa/NetDisk1/Shared
    writeable = yes
    directory mode = 777
    create mode = 777
    public = yes

De plus, si j'essaie d'utiliser chmod ou chown sur le point de montage (/media/alto...) la commande s'exécute sans aucun changement effectif.

ls du disque :

drwxrwxrwx 1 altocasa data     4096 Aug 15  2018  DRIVERs
-rwxrwxrwx 1 altocasa data  9401704 Dec  2  2019  DTTarget2.1.0.0072.exe
drwxrwxrwx 1 altocasa data     8192 Apr 14  2021  FILMs
-rwxrwxrwx 1 altocasa data 12218104 Mar 22  2021 'Fusion 360 Client Downloader.exe'
drwxrwxrwx 1 altocasa data     4096 Oct  4 16:03  ISO
-rwxrwxrwx 1 altocasa data     1091 May 12  2019  ObstacleAvoidV1.py
drwxrwxrwx 1 altocasa data        0 Oct 28  2016  Programmi
drwxrwxrwx 1 altocasa data     4096 Feb 12  2017 'System Volume Information'
drwxrwxrwx 1 altocasa data     4096 Apr  8  2021  Torrent
drwxrwxrwx 1 altocasa data      264 Feb  2 20:03  UNLISTED
drwxrwxrwx 1 altocasa data     4096 Mar 23  2021  Vpn
drwxrwxrwx 1 altocasa data     4096 Jan 27 15:01  html
drwxrwxrwx 1 altocasa data     4096 Jan 27 15:02  openrsd

Je suis littéralement à court d'options. Quelqu'un sait-il pourquoi un utilisateur (www-data) qui fait partie du groupe data ne peut pas lire ou écrire sur un dossier appartenant à data ?

Merci !