Fetching all emailaddresses on a server

In the process of setting up an external mailserver to process email before delivering to my DA-server, I'm looking for a way to populate a list of all existing addresses that the mailserver should accept mail for.

Is there an easy way of getting a list of *all* email-addresses that are valid on a given DirectAdmin system?

Things to note:
* Catchall addresses means all addresses are valid
* Majordomo addresses are not really stored anywhere (?)
* Alias-domains have valid email-addresses too
* Probably more

I was planning to use the API to do something like this:

* Fetch all domains (which there seems to be no API-call for)
* Fetch all email-options/settings for each domain

Instead, it looks like I have to do this:

* Recursively fetch all users created by other users
* Fetch all domains owned by the list of users I now have
* Fetch all email-options/settings for each domain

Am I way off here, or is this the way to do it?

Thanks for any pointers or ideas.

Both ways seem to be OK.

p.s. majordomo lists names can be found in /etc/virtual/<domainname>/majordomo/lists/
e.g. /etc/virtual/domain.com/majordomo/lists/mylist, where [email protected] is a list.

UPD: Remember about email redirects.

Don't forget per-user alias files.

All usernames in /etc/passwd accept mail unless otherwise blocked.

If you're using mbox email boxes, they're not created until after an email is received.

If you're using Maildir I'm not sure whether any of the directory chain is prepopulated or not; perhaps someone who's already checked can tell us.

Of course a completely different way of doing it would be to have your external mailserver check to see if it can deliver mail to a user before accepting mail for that user.

In otherwords, after the recipient is known, check to see if the mail is deliverable on your DirectAdmin server; if yes, accept, if not, refuse.

Jeff

jlasman said:

Don't forget per-user alias files.
All usernames in /etc/passwd accept mail unless otherwise blocked.

If you're using mbox email boxes, they're not created until after an email is received.

If you're using Maildir I'm not sure whether any of the directory chain is prepopulated or not; perhaps someone who's already checked can tell us.

Click to expand...

Is any of this information that I cannot get through the API? I would like to stick with the API as much as possible, to have a well defined interface to talk to.

jlasman said:

Of course a completely different way of doing it would be to have your external mailserver check to see if it can deliver mail to a user before accepting mail for that user.

Click to expand...

Yes, it had crossed my mind. My mailfilters are running postfix, so I looked into it to see if I could find some good documents describing it, and found this howto:

http://www.postfix.org/ADDRESS_VERIFICATION_README.html

I will take a look at that also. Somehow it feels like a more appealing solution.

kristian said:

Is any of this information that I cannot get through the API? I would like to stick with the API as much as possible, to have a well defined interface to talk to.

Click to expand...

As I recall, DirectAdmin doesn't interface with the alias files. So it probably doesn't have an api call for them. But any user with the knowhow and ftp can create an alias file.

So alias files are worth considering.

Jeff

kristian said:

http://www.postfix.org/ADDRESS_VERIFICATION_README.html

Click to expand...

Just for the archive: (Recipient) address verification is what I went with in the end. It was painless to set up, and with the absence of a full list of valid addresses, doesn't generate any more load on the backend (DA) servers than you would otherwise have.