Quotas

Cyrus IMAP features a flexible Quota scheme with support for limiting various resources, such as storage or number of folders or messages.

• Quota Roots
• Supported Quota Types

Monitor and Repair

Quotas may be monitored and repaired via the quota(8) command.

Controlling Quota Behavior

How restrictive quotas will be may be tailored to the needs of different sites, via the use of several settings in imapd.conf(5):

• lmtp_over_quota_perm_failure

• lmtp_over_quota_perm_failure

• lmtp_strict_quota

• quotawarnpercent

• quotawarnsize

• quotawarnmsg

• autocreate_quota

• autocreate_quota_messages

Quota Database

Quota information is stored either in a database (i.e. twoskip, skiplist) or in "quotalegacy" format, which is a filesystem hierarchy. This is controlled by the quota_db and quota_db_path settings in imapd.conf(5).

Converting Quotas Database

The cvt_cyrusdb(8) utility may be used to convert between formats. It's usage with quotalegacy is a special case, in that the first argument ("<old db>") will be the path to the base of the quotalegacy directory structure, not to a particular file.

For example, given this typical layout:

/var/lib/imap/
|            /quota/
|                  /A/
|                    /user/
|                         /bob/

The proper cvt_cyrusdb command would be:

cvt_cyrusdb /var/lib/imap/quota quotalegacy /var/lib/imap/quotas.db twoskip

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