Kopano Basic

Kopano Basic for ClearOS provides a powerful mail and groupware solution with:

  • Mail / Webmail
  • Contacts
  • Calendars
  • Tasks


If your system does not have this app available, you can install it via the Marketplace.

Because Kopano uses objects directly in OpenLDAP, Kopano is NOT compatible with accounts in Active Directory provided by the AD Connector app. While support does exist in Kopano for users that wish to modify their Active Directory Schema, this mode has neither been tested nor supported by ClearCenter

You can find this feature in the menu system at the following location:

<navigation>Server|Communication and Collaboration|Kopano Basic</navigation>

Purchase and Kopano Serial Number

After purchasing Kopano Basic through Marketplace, a serial number will be issued to you within one business day. You will need to enter this serial number into the ClearOS app page in order to fully activate your Kopano install. The serial number will be emailed to the address you have used when creating your ClearCenter Account.

Your Kopano serial number is not the same as your ClearCenter subscription serial number.

If you ever need to retrieve your serial number or did not receive an email, login to the ClearCenter Portal and navigate to “Account –> Asset Management –> Subscriptions”. Click on “View” to see a subscription's detail. See screenshot below that illustrates how to find your Kopano serial that is used in Webconfig.


The base mail domain is used by a number of apps: SMTP Server, IMAP, Mail Filter, etc. Each app saves this information in its own configuration file, but we really only want to see the domain in one place in the user interface. That's where the Mail Settings app comes in.

Account Manager

Go to <navigation>System|Account Manager|Account Manager</navigation> to make sure the accounts system (users/groups) is running.

Mail Settings

Go to <navigation>System|Settings|Mail Settings</navigation> to set the Mail Domain and Mail Hostname. You can check the app's documentation here .


Go to <navigation>System|Accounts|Users</navigation> to create a few users. Please make sure the SMTP Server User and Kopano Account are enabled for the user. Feel free to fill out the contact information too - this information is shown in Kopano's address book!


Go to <navigation>System|Accounts|Groups</navigation> to create a group or two. You will see a new option when adding/editing a group: Distribution List. If you leave this option enabled, the group becomes a mail distribution list (e.g. will go to all the members of the sales group).

Kopano Settings

Go to <navigation>Server|Communication and Collaboration|Kopano Basic</navigation> and start all the services (if not running).

  • Change the POP and IMAP ports if required
Clearfoundation recommend you leave these set to default unless you have strong reason to change

Clearcenter recommend the use of the secure protocols POPS and IMAPS over the insecure protocols POP and IMAP
  • A serial number is provided within one business day of making the Kopano purchase via Marketplace. Add this serial number to your install via the web-based administration tool.

  • Optionally you can set up backups.

Webapp Access

You can access the webapp interface by visiting https://your_Clearos_FQDN_LAN_IP_or_WANIP/webapp.

Backing Up and Restoring

The principal document for backing up and restoring e-mails in here on Kopano's website.

They have a tool called kopano-backup but it does not restore to the exact same state as things like the last modified date will be the time of the restore and not the time of the backup.

Restoring data up to 30 days old

In Kopano, when you delete a message, it only does a soft-delete. It is possible to recover these messages with the Restore deleted items in many MAPI clients. The Kopano Webapp can do this. This function can be performed by the user.

Disaster Recovery

For full disaster recovery both the MariaDB database and the attachments need to be backed up. To dump the whole system-mariadb database to /tmp/filename.sql, use the following command:

/usr/clearos/sandbox/usr/bin/mysqldump --port=3308 --single-transaction --routines --all-databases \
    --password=$(awk '{print $3}' /var/clearos/system_database/root) > /tmp/filename.sql

Attachments are stored in /var/lib/kopano and can be copied out using tools such as rsync, tar or cp. If using rsync there is a useful switch, –link-dest which allows you to keep rolling backups with minimal storage space (if a file is need my multiple backups, it is only, in reality, stored once). There is a good explanation here and an example of using rsync with the –link-dest switch can be found here .

The kopano-backup tool

This is used by the webconfig. It initially takes a full backup and then incremental backups if it finds a full backup in the destination folder.

To keep the backup under control, you may want to periodically run it with the “–purge N” option. Please check the man page.

Restoring from kopano-backup

This also uses the kopano-backup utility with the “–restore” switch. There are usage examples at the end of the man page.

Incremental Backups for Offline Storage

The backup taken from the webconfig is effectively a snapshot of the whole system and, if copying offline for security, a full backup must be copied each time. Internally the kopano-backup is working incrementally so it is fast, but the storage is not incremental.

If you want incremental storage so it is suitable to be written incrementally elsewhere e.g. with rsync, then you can run kopano-backup manually with the –differential option.

The downside of this approach is that, when restoring, you would need to specify the diff on disk from where you want to restore the item (kopano-backup currently does not traverse all diffs). For a full restore you would have to merge the differential files back in one first.

Rsync with the –link-dest switch is a very powerful backup tool which minimises file storage.

Using your own certificates for Kopano POPS/IMAPS/Outlook

If you want to use your own certificates for POPS/IMAPS and Outlook (Using Exchange Sync via z-push) you can if you follow these instructions but please be careful.

This does not apply to the Webapp. The Webapp just uses the certificates configured in the default Web Server

User certificates are either found in /etc/clearos/certificate_manager.d if you have imported them through the Certificate Manager or are in /etc/letsencrypt/live/{your_certificate_name} if you want to use a Let's Encrypt certificate.

For Let's Encrypt certificates, please use this guide.

For you own imported certificates, start with checking your certificates in /etc/clearos/certificate_manager.d. If you certificate contains a single certificate, you will need to create a file with the contents of both the certificate and the intermediate certificate. The certificate should go above the intermediate certificate. Give the certificate file ownership of root:ssl-cert e.g:

chown root:ssl-cert /etc/clearos/certificate_manager.d/my_combined_file

Similarly, make sure your certificate is owned by root:ssl-cert.

Then edit /etc/kopano/server.cfg and point the entries:


to your own certificates.

Optionally, also edit /etc/kopano/ical.cfg change:


And point these to your own certificates.

Then restart Kopano with a:

Do not change the /etc/kopano/gateway/cert.pem and /etc/kopano/gateway/privkey.pem file as the webconfig can and will overwrite them from time to time. If you change them to symlinks to your own certificates you risk stopping the webserver and webconfig as well and your own certificates will get overwritten.

Test Repositories

ClearCenter operates a separate repository for testing the latest stable releases of Kopano and the supporting packages. If you would like to run the latest version and it is not installed by default from the ClearOS Marketplace, try upgrading with the following command:

ENABLE_BETA=True yum upgrade app-kopano kopano*
content/en_us/7_ug_kopano_basic.txt · Last modified: 2019/12/20 15:45 by nickh