Ich schätze mal du solltest das in der smb.conf festlegen können.
[global]
workgroup = Your_Workgroup
guest account = nobody
security = share
browseable = yes
guest ok = yes
guest only = no
log level = 1
max log size = 100
encrypt passwords = yes
dns proxy = no
[smbshare1]
path=/opt/share/samba1
writeable = yes
browseable = yes
[smbshare2]
path=/opt/share/samba2
writeable = yes
browseable = yes
guest ok = yes auf no stellen. Kann ich grad nicht ausprobieren. Zudem kannst du über "/etc/smbpasswd" User anlegen.