set up mailserver without sql

priit · 03-07-2019, 03:38 AM

There is lot of manuals with examples how to set up mailserver.
Some of them describes to install postfix, dovecot and mysql.
Others describe You have to install postfix and dovecot only. That's it.

My question is why do I need sql database like Mysql or Mariadb if mailserver runs freely without them?

Is using sql database like mysql or mariadb, gives some extra security to preserve mailboxes and all its content ? Or if you dont use those, then Dovecot does sql job by itself ?

serafean · 03-07-2019, 06:02 AM

Hi,

you can use PAM for authentication, thus having a direct mapping between unix users an mailboxes.
A database is the most common usecase because it allows for "virtual" users.

I personally have a dovecot+postfix setup to use PAM for auth. Dovecot performs authentication. Postfix asks dovecot for permission through LMTP.

joe_2000 · 03-07-2019, 06:31 AM

Quote:

Originally Posted by serafean

A database is the most common usecase because it allows for "virtual" users.

I am using virtual users on my postfix / dovecot setup with just plain text configuration, so that's definitely possible, too.

priit · 03-08-2019, 12:53 AM

Thanks for quick answers. I expect using sql is more secure way to hold, store data (virtual users, mail accounts, emails) on server harddrive? Does'nt affect network and login security.

joe_2000 · 03-08-2019, 01:58 AM

Quote:

Originally Posted by priit

Thanks for quick answers. I expect using sql is more secure way to hold, store data (virtual users, mail accounts, emails) on harddrive? Does'nt affect network and login security.

I don't think so. Even the opposite. Making the data available through sql (and possibly an administrator web frontend) would rather decrease security imho. I think it's more a matter of convenience and maintainability for large installs. Would be interested to hear counter arguments to the above though.

priit · 03-08-2019, 04:53 AM

Quote:

Originally Posted by joe_2000

it's more a matter of convenience and maintainability for large installs.

Idea is to built a mailserver with around 150 + accounts, max. 200 not more. So using sql is'nt definitely important?
How about later managing mailboxes: increase/decrease box size, send/receive size limit etc ? Does it concerns to sql base ?
Backup purpose. With sql base coping faster than without it ?

serafean · 03-08-2019, 06:27 AM

Security - Anything that doesn't store passwords in plain text and/or in a readable format is not insecure.
Mails pretty much have to be stored in plaintext. The admin will always be able to read them.
As for mailbox quotas, pick your approach : https://wiki2.dovecot.org/Quota

At 200 users, IMO a db won't be any faster than a passwd file. Just a bit more complex to set up.