Using quotas to manage the size of user mail files

Users may receive and save a high volume of e-mail, including their own sent messages, in their mail files. Large mail files can overwhelm a server's disk capacity and reduce the performance of the mail client. Because you generally cannot provide users with unlimited storage space, set a size limit, or database quota, for each mail file. When delivering mail to a user's mail file, the Router checks the current size of the mail file against the specified quota.

You set mail database quotas on the Mail pane when registering users with Advanced user registration in the Domino® Administrator or by setting a database size quota from the Files tab in the Tools pane in the Domino® Administrator.

You can configure the Router to respond in several ways when a mail file exceeds its quota, each representing a higher level of enforcement. The least restrictive response is to have the Router issue automatic notifications to users when their mail files exceed the quota. If users fail to respond to notifications, you can hold pending messages in MAIL.BOX or return messages to the senders as undeliverable until the users reduce the size of their mail files.

In addition to setting a quota, you can configure a warning threshold and use it as the basis for providing users with advance notice that their mail files have grown too large. For example, you might set a warning threshold of 25MB on a mail file that has a 30MB quota. In the Configuration Settings document, you can enable the Router to send notifications to users who exceed their warning threshold. If you enable this option, the Router delivers an Quota Warning Report to users whose mail files exceed the warning threshold. Sending such warnings allows users to reduce the size of their mail files before they exceed the quota.

When used with the setting Hold mail and retry in the Over quota enforcement field of the Configuration Settings document, the NOTES.INI setting, MailTimeout, designates the number of days that mail is held for the user when the user's mail file exceeds the mail file size quota. By default, MailTimeout=1. If a user's mail file exceeds the quota for mail file size, mail is held for that user for one day. If the user does not reduce the size of the mail file within one day, mail is returned to the sender as undeliverable. If the mail file size is reduced during that one day, mail that was being held is delivered. You may want to use a value greater than one so that users are allowed a reasonable grace period before their mail is returned to the sender. For example, if a user is on vacation and is notified that their mail file exceeds the set mail file size quota, the user would not be able to reduce the size of the mail file. After being held for one day, mail would be returned to the sender as undeliverable. You can set a value greater than one (1) to allow mail to be held for several days before being returned to the sender.

Along with the methods the Router uses to enforce quotas, the Notes® client also displays a warning to any user who has exceeded their designated warning threshold or quota whenever the user attempts to send mail.