Summary

Are you an ISP and would you like to set limits for your users as is mailbox limits, send message limits, data limits, disk quota etc? This article will help you.

Global limits

• Max message size

Here you can set maximum message size, which has highest priority in compare to other message limits. This limit is global, so if some user is allowed to send bigger message, this is more important so the message will not be accepted by mail server.
Mail service --> SMTP service --> general tab

• Max recipients limit

Also this limitation is global, so it applies on all users in mail server. You can choose from two types of recipients limitation. Client and server.
Mail service --> SMTP service --> general tab

• Number of incoming and outgoing connections

Maximum number of simultaneous connections. This can help you in optimizing server load and also helps you find, that something is disordered (when normally max connections are 50 and after 750, something is wrong). Set number a little bit bigger than average load (can be found in statistics or services).
System --> Services --> SMTP --> other tab

Domain limits

• Maximum accounts number

Adjusts maximum number of accounts in selected domain.
Domains & Accounts --> Management --> select domain --> limits tab

• Disk quota

You can set disk quota in kB, MB or GB which is applied to selected domain. After this quota will exceed, all messages will be rejected by error 5.2.2. You can easily check used data of each domain in Status --> Domain section.
Domains & Accounts --> Management --> select domain --> limits tab

• Send out data limitation

If your provider controls amount of data you are sending or you have to block big amount of outgoing data, use this limitation to help you.
Domains & Accounts --> Management --> select domain --> limits tab

• Send out messages number limitation

To makes your server more secure, it's better to use this limitation. Imagine situation, that some of your accounts have been stolen by spammers. If this limitation will be set to whole domain (be careful, set bigger number than usually you are sending) you can avoid this annoying situation. This limitation can be also set on user's level, which is may be easily to set, due to ability to guess amount of messages.
Domains & Accounts --> Management --> select domain --> limits tab

Users limits

• Mailbox size

You can set maximum size of each user's mailbox to any number. There are two ways hot to do that. You can set that "globally" in
Domains & Accounts --> Management --> select domain --> limits tab or you can set that individually for each user. As in global limits were mentioned, global limitation has highest priority, so if user tom@merak.com has it's own limitation of INBOX set to 300MB but domain limitation is set to 250MB, he will be able to dispose only 250MB.
Domains & Accounts --> Management --> select domain --> select user --> limits tab

• Max sent message size

Here you can define size of each message which will be maximum a day for that user to sent.
Domains & Accounts --> Management --> select domain --> select user --> limits tab

• Send out data limitation

As in domain level has been mentioned, here it's in user's level. You can define amount of data which can be sent by concrete user a day.
Domains & Accounts --> Management --> select domain --> select user --> limits tab

• Send out messages number limitation

Again, as in domain level, you can define for each user number of messages which can't be overreached. It's very useful to avoid some intrusion in the server by spammers.
Domains & Accounts --> Management --> select domain --> select user --> limits tab

KB20070622316
made by LukasP