Email sending limits and throttling – iRedmail free edition

iRedMail is:
1. A ZERO COST, fully fledged, full-featured mail server solution. All components are free and open source software
2. It support unlimited domains and email accounts.
2. SpamAssassin, ClamAV, SPF, DKIM, greylisting, whitelisting, blacklisting.
3. Stores mail accounts in your favorite backend: OpenLDAP, MySQL, MariaDB, PostgreSQL.
4. Supports major Linux distros

Throttling

iRedmail supports following level of throttling for email limits.
Global, per-domain and per-user throttling based on: max size of single message, number of max inbound/outbound messages per time unit.

iRedmail uses a component named iredpad for this. With iRedmail Pro version, you can configure these settings through GUI(iRedadmin panel). However they are not available through GUI for free version. The feature is enabled though we will have to modify them through database directly.

So the database is “iredapd” and table is “throttle”.

Here are some examples

1. Allow user `user@domain.com` to send 50 mails in 5 minutes (period=300):

INSERT INTO throttle (account, kind, priority, period, msg_size, max_msgs, max_quota) VALUES (‘user@domain.com’,’outbound’,100,300,0,50,0);

2. Set global limit of 500 mails per day and a maximum single mail size of 55MB

INSERT INTO throttle (account, kind, priority, period, msg_size, max_msgs, max_quota) VALUES (‘@.’,’outbound’,0,86400,57671680,500,0);

57671680 bytes = 55MB
86400 – 1 Day

# Technical details of throttle plugin
# ————-
#
# Currently you may throttle based on:
#
# – amount of mails sent over a given period of time
# – accumulated mail size sent over a given period of time
# – size of singe message
#
# Eg: You can enforce that user@domain.com does not send more than 1000 mails
# or 1GB of mail (whichever limit is hit first) in 5 minute.
#
# Possible throttling address:
#
# *) Full email address: user@domain.com
# *) Domain name (with a prefixed ‘@’): @domain.com
# *) Sub-domain name (with a prefixed ‘@.’): @.domain.com
# *) IP address: 192.168.1.1
# *) IP network: 192.168.1.*
# *) Catch-all for email address: ‘@.’ (note, the dot is required)
# *) Catch-all for IP address: ‘@ip’
#
# Priorities of different thorttle address (larger digital number has higher priority):
#
# *) email: 100 # e.g. ‘user@domain.com’. Highest priority
# *) wildcard_addr: 90 # e.g. `user@*`. used in plugin `amavisd_wblist`
# # as wildcard sender. e.g. ‘user@*`
# *) ip: 80 # e.g. 173.254.22.21
# *) wildcard_ip: 70 # e.g. 173.254.22.*
# *) cidr: 70 # e.g. 173.254.22.0/24
# *) domain: 60 # e.g. @domain.com
# *) subdomain: 50 # e.g. @.domain.com
# *) top_level_domain: 40 # e.g. @com, @org
# *) catchall: 0 # ‘@.’. Lowest priority

Please note that priority for global setting is 0 and priority of a single user is 100.