8. Configuration considerations

This chapter can be used as a guideline for configuration choices in the archiver rollout, based on the two scenarions of either storage or history based primary usage. All configuration options will be explained together with typical value for the setting.

  • Archive permissions

When the archiver is deployed for storage optimalisation users will require the same permissions on the archive mailbox as on their primary mailbox. In a history based archive the permissions on the archive mailbox will be typically read-only, so the user can delete no items from the archive. With the Kopano Archiver the default permissions can be set when the a user is attached to an archive mailbox.

  • Copying time

In a storage based archive the message will be typically archived after 30 or 60 days, so only the more important will be copied to the archive mailbox and non-important email will not take any space on the archive server as it will be removed prior to the archiving actions. In a history based archive the messages will be automatically archived at delivery time. In this case it’s not necessary to set the archive time, as the messages are already in the archive store available. To use the history based archive feature both the delivery dagent and spooler need to have the option archive_enabled set to yes in order to store directly all emails at receive/sent time.

  • Stubbing time

In both store and history based archives, stubbing will typically be set to 30-60 days. When choosing the right stubbing time, please keep in mind the body and attachments of stubbed emails can only be accessed when there is an online connection to the archive server. For this reason the stubbing time should not be set to low.

  • Deleting time

As the deletion time will make items unavailable in the primary mailbox, the value will be typically have a value of 6 months or 1 year. After this time users normally don’t open those emails that frequently anymore and in case the emails should be access, the archive mailbox can be added as a delegate mailbox. Having a high time for this setting will result in larger amount of items in a folder. When users should always access all items from the primary mailbox, the delete_enable setting setting of archiver should be set to No.

  • Purge time

The purge setting will delete items completely from the archive mailbox, so emails will not be available at all. In case of a history based archive, so users will not be able to cleanup their own archive mailbox, this setting is recommended to use. When this setting is not configured, items will be never removed from the archive server. The typical time for this setting is 5-7 years, depending on your considerations and reasons for using the history based archive. When using the storage based archive the prefered time can be configured based on user experience and the average lifetime of items in mailboxes.


This configuration option should be carefully considered including any legal aspects, as it will remove items from the email system.

  • Quota

Like a normal installation of Kopano, archive servers can also have quotas configured. When using a history based archive setup a reached quota will stop the history archiving process, so in this case quota should not be set. In case of a storage based archive the archive is typically configured to reduce the data size on the primary server. When the quotas are set on the archive server the archive process will not be able to archive emails when the quota is reached and emails will be kept on the primary server, so therefore it’s not recommended to configure quota on the archive.

  • Quota on primary server

Also when the Kopano Archiver is integrated with a running KC environment mailbox quotas can be configured. When having the stubbing setting enabled, the stubbed items will only use around 1kB of size in the database.