groupadd smbgrp
useradd user1
usermod -aG smbgrp user1
chgrp smbgrp /folder
smbpasswd -a user1

cat << EOF > /etc/samba/smb.conf
[global]
workgroup = AUGIN
security = user
map to guest = bad user
wins support = no
dns proxy = no
 
[folder]
path = /folder
valid users = @smbgrp
guest ok = no
browsable = yes
writable = yes
map to guest = bad user
EOF