On Sat, Sep 01, 2018 at 05:50:27PM +0000, Gilles Chehade wrote: > > I'll describe how things work in this mail so it serves as reference for > future questions regarding aliases, virtual and userbase: > > Aliases and virtuals are mutually exclusive features that operate at the > same level, converting an e-mail address into a local user. > > Userbases operate at a lower level, allowing to lookup system details of > a local user such as uid, gid and home directory. > > You don't have to have aliases or virtuals, but you MUST have a userbase > which defaults to the system user database when you don't specify one. > > Aliases and virtuals can be seen as functions that take an e-mail as the > input and produce usernames that _MUST_ exist in the underlying userbase > as the output, otherwise the recipient will be rejected. > > The difference between aliases and virtuals is subtle but simple: > > - aliases assume that all users on the system are allowed to get e-mails > and that the user-part of recipient e-mail addresses are the usernames > on the system. the mechanism allows you to provide an OPTIONAL list of > transformations in case some recipients have user-parts that are not a > system user, and it assumes that if no alias is found, then user-parts > must be looked up as real usernames. > > - virtuals assume that users are NOT allowed to get e-mails, unless they > are EXPLICITELY allowed on a list. either a transform is found and the > recipient is converted into a username, or the recipient is rejected. > > > You can receive e-mail if you're not in the aliases list, if you have an > account on the system with a username matching the user-part. > > You can't receive e-mail if you're not in the virtuals list, EVEN if you > have an account matching the user-part. > > > Now with that being said, converting a recipient into a username doesn't > help us much if that username doesn't exist for real. We need a uid, gid > and a home directory, so no matter if you used aliases, virtuals or none > of them, the username behind a recipient must be found in the user base. >
Thanks, this helps a lot Just one more question. You reply sounds like I should choose either aliases or virtual, but not both. Is this correct? What about programs such as femail? Do they work fine with just virtuals? Thanks Chris Bennett -- You received this mail because you are subscribed to [email protected] To unsubscribe, send a mail to: [email protected]
