Kartik Vaidyanathan wrote:

Well one major doubt that was prevailing was that do i need to create a system account for each person in order to send/receive mails, and from both (Sven Kirmess & Johannes Berg ) your mails i gather it is a must.

That's not correct. Take a look at http://wiki.dovecot.org/. They have an example with "Virtual user support with OpenLDAP" and "Virtual user support with PostgreSQL". You either use LDAP or a PostgreSQL database to store the mail users. The mail can then be stored in any directory.

The software that i am creating , which is going developed in JSP, will take a new users name and password and create a account for him by executing a shell script in my linux machine.

Should be possible. You have to create the account in SQL or LDAP with that script...

I assume yahoo also does something similar to this to create new mail boxes for any new user.

You use the mailbox for the mailing list archive?

In fact this very mail that i have received from you is because i have subscribed to the dovecott mailing list. How do you think dovecott has been able to accomplish this.

That's done by the mail delivery agent (sendmail, postfix). If you just have to send a mail to each recepient you do not need an IMAP server.

2.Will the mail server support me in anyway by giving me some functionality to add users, thereby creating maildir's (imap) for the users.

No. You have to add the user to the database (LDAP, SQL or /etc/passwd) and create the directory yourself.

3.Dont I need to know the admin login and passwd, to create users?

Yes and no. You need either the root account to create an entry in /etc/passwd or a user which is able to write to SQL or LDAP. Depending on which database you use.

3.Lastly i know this is not that prevalent a question -> I was told mail man does a similar job as to what my software will do. Do you know how mailman works (or even yahoogroups)?.

You probably should ask in as mailman group. They might know better. I will explain how majordomo does this. Majordomo is abother mailing list software (Probably not the best one, but the one I know).

In the /etc/aliases file (which belongs to sendmail, postfix or whatever is your MDA. This files does _not_ belong to dovecot.) there is an entry like this:

dovecot: :include:/usr/local/majordomo/lists/dovecot

Then, the file /usr/local/majordomo/lists/dovecot contains a list of all the persons subscribed to this mailing list. One email address per line. The MDA does send each mail sent to dovecot individually to each entry in the /usr/local/majordomo/lists/dovecot file. The mailing list software does now manage the /usr/local/majordomo/lists/dovecot (adding and removing users). To create a new list, you have to add an entry to /etc/aliases.

Please let me know if the answer does not match to your question. ;-)

Sven

On Fri, 16 Apr 2004, Kartik Vaidyanathan wrote:

Hi,

I have actually configured dovecot because i required a mail server in order to build a mailing list manager.A mail list manager is something in the likes of yahoogroups, where each group in my case must have a mailbox.

You need a MTA, such as postfix, qmail, sendmail, exim, etc. It's more important than an imap server for what you want to do.

Actually, I don't really understand why you need an imap server when making a mailinglist manager.

1. I am using Debian OS. The software that i am creating , which is going developed in JSP, will take a new users name and password and create a account for him by executing a shell script in my linux machine.I assume yahoo also does something similar to this to create new mail boxes for any new user.Please correct me if i am wrong.

I don't know, I don't work at yahoo. But I think they create virtual users in database systems for email, I can't imagine all of the users they have are in one passwd file on one tiny machine.

In fact this very mail that i have received from you is because i have subscribed to the dovecott mailing list. How do you think dovecott has been able to accomplish this. Is it not because that dovecott has a mailbox in the group name "dovecott" in some system, that internally does the sending of mails to all those in the groups refering to some database.

Dovecot doesn't have anything to do with that. It's mostly the MTA, aided by the mailing list manager.

Here's how majordomo (popular mailinglist manager) works:

Bob wants to subscribe to the pigeonhole mailinglist. He emails or enters his email address in a web form so it ends up in a database file with all the other users on that list. The mailinglist manager's job is to take care of adding (or removing) email addresses to (from) that file; it adds Bob's address.

When an email is sent to pigeonhole@pigeonhole.org, the mailer daemon (MTA) receives this email, and instead of delivering it to a local user, either it (1) delivers it to a pipe - it passes the email to the mailinglist software, which then just generates an email that replaces the original destination with the list of email addresses; or (2) the mailer daemon itself forwards the email by alias expansion to the list of email addresses the mailinglist software made.

In the former case, the mailinglist manager reads the original message and replaces the address with all those in the list's database; in the latter case, basically the only thing a mailinglist manager does, is taking care of an error-free database file with email addresses so the MTA can forward the email to the addresses in this file.

Because Bob's email address is in this file, his address will be inserted in the headers of the message, and he will receive the email.

2.Will the mail server support me in anyway by giving me some functionality to add users, thereby creating maildir's (imap) for the users.

No, adding users is not the job of a mail server daemon. Or of an imap server. Usually, you don't allow people to add users to your system, for obvious reasons.

If you want to add users to a mailing list, you don't need accounts for those users, only when you also want to provide them with an email address.

What do you want to do: provide email addresses, or a mailinglist manager?

3.Dont I need to know the admin login and passwd, to create users?

Yes, ofcourse. Unless your users are in a database server, in that case you need the ability to add records to that database.

(Shared webhosting accounts usually allow adding virtual users, if that's the reasoning behind your question.)

3.Lastly i know this is not that prevalent a question -> I was told mail man does a similar job as to what my software will do.Do you know how mailman works (or even yahoogroups)?.

Not precisely, but pretty much like I said above. You can check out the documentation and source code of said software.

Yahoogroups probably uses custom written software, but still based on the simple approach of a mailinglist manager taking care of a list of subscribers, and the mailer daemon either itself or by aid of an external program multiplicating the recipients.

A mailinglist manager has nothing to do with Dovecot. Dovecot has nothing to do with *sending* email, only with retrieving it from a system with IMAP of POP. It's the end-of-the-line for emails, delivery to final destination; it does not forward or duplicate.

Please enlighten me on the above issues. Thanks a lot for you time.

I'll send you the bill later. ;)

Regards Kartik