Thread: Postfix User Mailbox Quota

I have been doing some research on implementing a user quota on a production mail server. It seems like this is a feature that is missing in postfix, and in order to do so, one must compile the program with an external plugin. Can anyone confirm or deny this?

Are you talking about disk quota or mailbox size or outgoing / incoming email quota (like only allow 200emails per day)?

Almost all of them can be implemented in postfix. but we need more info..

Sorry for not being more clear - I'm referring to actual disk quota. I'd like to set a 300mb limit on all users, but have the ability to change the limit of an individual user on the fly.

For virtual email box use:

Code:

virtual_mailbox_limit = size_in_bytes

For direct loca mailbox use:

Code:

mailbox_size_limit = size_in_bytes

If you are looking to set different size for different users use program such as Postfixadmin with mysql backend+virtual mail box size.

Thanks for getting back to me Vivek. I'm still a rookie at this whole unix admin thing - but I subscribe to your mailing list and find it very informative.

As it turns out, the main.cf file already has those limits set:

message_size_limit = 20240000
virtual_mailbox_limit = 30480000
mailbox_size_limit = 30480000

However, they're not being enforced, as I have several accounts that are far above quota. Any thoughts?

Are you using any other external command that are executed by postfix local delivery agent? Also, you need to configure IMAP or POP3 server such as dovecot. For e.g. following line must exists to work it correctly:

Code:

virtual_mailbox_limit_inbox = yes

Here is what I typically use in main.cf

Code:

mailbox_size_limit = 51200000
message_size_limit = 10240000
virtual_mailbox_base = /nas/mailstorage/virtual
virtual_mailbox_domains = proxy:mysql:/usr/local/etc/postfix/mysql_virtual_domains_maps.cf
virtual_mailbox_limit = 51200000
virtual_mailbox_limit_inbox = yes
virtual_mailbox_limit_maps = proxy:mysql:/usr/local/etc/postfix/mysql_virtual_mailbox_limit_maps.cf
virtual_mailbox_limit_override = yes
virtual_mailbox_lock = fcntl, dotlock
virtual_mailbox_maps = proxy:mysql:/usr/local/etc/postfix/mysql_virtual_mailbox_maps.cf

Oh, if you are not using mysql as backend, then you need something as follows:

Code:

# disk quotas config per mailbox
virtual_mailbox_limit_maps = hash:/etc/postfix/vquota
virtual_mailbox_limit_override = yes
# A maximum limit of a mailbox
virtual_mailbox_limit = 100000000
# Limits only INBOX part for IMAP
virtual_mailbox_limit_inbox = yes

And /etc/postfix/vquota:

Code:

# 2048000 bytes limit
user1@domain.com    2048000
user2@domain.com    2048000 
# 5192000 bytes limit
user3@domain.com    5192000
# no limit
user4@domain.com    0