OpenCloud

What OpenCloud does

OpenCloud is a file sync, sharing and collaboration server developed by OpenCloud GmbH, part of the Berlin-based Heinlein Group. People use it through a web interface, desktop apps for Windows, macOS and Linux, and mobile apps for iOS and Android (from the App Store, Play Store and F-Droid). Files can be shared with colleagues or groups, or sent to outsiders through password-protected links. Versions are saved automatically and can be restored, and search covers both file contents and metadata, with tags for organizing.

The central idea is spaces: shared workspaces for teams and projects that own their files, so content stays available when members change. Office documents are edited in the browser with Collabora. Federation over the Open Cloud Mesh protocol connects OpenCloud with other installations and with compatible platforms, which the datasheet lists as including CERNBox, ownCloud, Nextcloud and Seafile. Calendars and contacts can be used from common calendar and contacts clients.

Architecture and security

The server is written in Go and, like ownCloud Infinite Scale, uses no database: files and metadata are stored directly on the storage. Backups can therefore be taken as storage snapshots, with no database dump to coordinate. Users sign in through OpenID Connect, using the embedded identity provider or an external one such as Keycloak; Entra ID and ADFS integration are documented. The built-in user management is intended for up to 500 users, for example a family or a small organization.

The datasheet lists TLS for transport and server-side encryption through S3 SSE when an S3 bucket is used. End-to-end encryption is not documented. Other security features include role-based access control, two-factor authentication, SSO through LDAP, SAML or OAuth, audit trails, antivirus scanning with ClamAV or any ICAP scanner, and a file firewall that blocks chosen file types.

Self-hosting OpenCloud

The recommended way to run OpenCloud is with containers, using Docker Compose or Podman. Production installs need Linux; macOS and Windows WSL are for testing. Storage must be a fully POSIX-compliant filesystem such as ext4, XFS, ZFS, CephFS or NFS 4.2 or later, with extended attributes for the posix driver, or an S3 bucket for the S3 driver.

Hardware needs are modest at the low end: the documentation names a Raspberry Pi 3 class machine, a 1 GHz single core and 512 MB of RAM for up to 10 users, and a 2 GHz dual core with 8 GB of RAM for up to 1,000 users. OpenCloud also runs as a single binary on bare metal, but that is not officially supported and integrations such as Collabora, Tika search and antivirus are not documented for it. Helm charts for Kubernetes are available only with a professional or premium subscription.

Hosted version

OpenCloud GmbH does not run its own public hosted service. The website and datasheet say SaaS and managed hosting are available through partners. The company sells subscriptions with support and updates for professional use.

Limitations

Kubernetes deployment through the official Helm charts requires a paid subscription. The storage must meet specific POSIX requirements, which can rule out some network filesystems. There is no documented end-to-end encryption, and no hosted service from the developer itself.

Who it suits

OpenCloud fits public bodies, schools, research groups and businesses that want a file platform with team spaces and accessible web design, and households that want a light server for a few users. Compare it with Nextcloud if you also need calendars, chat and many add-ons.