I have a cifs mounted filesystem and I will like to know, does
sudo postconf -e 'home_mailbox = Maildir/' mean that Maildir is chosen as default mailbox format or it just specifies a directory where an email is meant to be stored?
As far as I know, there are two ways that postfix will store email. Either in the mbox format which is a single file with delimiters and what not to help separate the messages or, in the Maildir format which keeps each message in a separate file and each virtual directory in the email server is a real directory.
When you specify the home_mailbox with a / at the end then it means that you are telling postfix to use Maildir. Without the / then it uses mbox. The part before that is the name of the mbox or Maildir that you are storing and can be called anything but most people prefer to use the name Maildir/ as it's more accurate of the content.
You can technically use
Another option would be to use