No, the 'guest' user with 'guest ok = yes' set on a share is generally the user 'nobody' which doesn't have a password. What you could do is create a user with a password, remove 'map to guest = bad user' from global and 'guest ok = yes' from the share, add 'valid user = your_new_user' to the share and use the username and password when connecting to the ...
Okay, here is the minimum you need for a guest only share, that doesn't use SMBv1:
security = USER
map to guest = Bad User
client min protocol = SMB2
server min protocol = SMB2
path = /smbshare
read only = No
guest ok = yes
guest only = yes
When you have got that working and then want authenticated users, ...
I think I figured out the problem: You mention you want no security, so I suppose you didn't add any user and ran smbpasswd. User ecb may be the user you login to your Debian system.
Yet on your config you have security = user, which means user authentication.
So for no authentication you only need:
map to guest = Bad User
Why the permissions are set as they are?
When a Unix-style program creates a new file, it will specify initial permissions for it. These initial permissions specified are typically 0666 or rw-rw-rw- for regular files, and 0777 or rwxrwxrwx for directories or executable files. This is something coded right into each program and not easily changeable.
OK, have you created users with 'smbpasswd -a username' (needs to be run as root) ?
If you haven't, then your guest account 'myuser' will not work. This means that no one will be able to access your share.
Authentication (based on your smb.conf) works like this:
A user connects to Samba and if the user is known and supplies the correct password, they are ...
Finally found it. The samba-ad-dc service was never started.
Details on fixing that are at https://wiki.samba.org/index.php/Managing_the_Samba_AD_DC_Service_Using_Systemd
No idea why the first page never referenced the second. Still some issues, but that at least got me past this problem.
It sounds like your Samba share is on the root partition. If you expect this to be the largest section, you can:
Copy the entire contents of the Samba share to the 2TB drive.
Delete the contents of the old Samba share, but keep the folder. E.g. If your share is in /opt/samba, delete everything inside /opt/samba but keep the folder.
Mount the 2TB drive at /...