Hi!
Samba4 require ACL and XATTR. I can install it locally because I did this:
[proxmox01]
apt-get install acl attr
tune2fs -o user_xattr,acl /dev/sda1
tune2fs -o user_xattr,acl /dev/mapper/pve-data
tune2fs -o user_xattr,acl /dev/mapper/pve-root
nano /etc/fstab
<file system> <mount point>...