Set OWNCLOUD_DOMAIN, OWNCLOUD_ADMIN_PASSWORD, DB_PASSWORD and DB_ROOT_PASSWORD.
Map the domain to port 8080 and deploy. The first start installs ownCloud and creates the admin account.
Log in with OWNCLOUD_ADMIN_USERNAME / OWNCLOUD_ADMIN_PASSWORD.

Health check: /usr/bin/healthcheck, the image's own script, also the compose healthcheck. It requests /status.php on port 8080.

Every start runs occ upgrade when config.php on owncloud-data says ownCloud is installed, and a fresh install otherwise. A new image version is therefore migrated on the next deploy, against whatever database db holds.

Environment

Variable	Default	Purpose
`OWNCLOUD_DOMAIN`	—	Public hostname, without scheme
`OWNCLOUD_ADMIN_USERNAME` / `OWNCLOUD_ADMIN_PASSWORD`	`admin` / —	Admin account
`DB_NAME` / `DB_USER` / `DB_PASSWORD`	`owncloud` / `owncloud` / —	Database credentials, read by both containers
`DB_ROOT_PASSWORD`	—	MariaDB root password

OWNCLOUD_DOMAIN also fills OWNCLOUD_TRUSTED_DOMAINS; ownCloud rejects requests for any host not on that list.

TLS ends at the proxy, so ownCloud sees plain HTTP. OWNCLOUD_OVERWRITE_PROTOCOL makes the URLs it generates https, and OWNCLOUD_PROTOCOL does the same for the URL occ and cron jobs use in links.

The admin variables are read only by the first-start install. Changing them later does not change the account; use the web UI or occ user:resetpassword.

The database credentials are stored inside the MariaDB data directory when it is first created. Changing them in the environment afterwards breaks the connection rather than changing the password.

Storage

Volume	Mount	Holds
`owncloud-data`	`/mnt/data`	User files, apps, `config.php`
`db-data`	`/var/lib/mysql`	The database
`cache-data`	`/data`	Redis locks and cache

The Redis volume follows ownCloud's own compose. Its contents are rebuilt after a restart, but the redis image declares /data a volume, so without a named one Docker creates an anonymous volume on every recreate.

Images

owncloud/server:11 tracks the 11.x line, so patch releases arrive on the next deploy and a move to a new major stays a deliberate upgrade. ownCloud's own compose pins a full version instead.

mariadb:10.11 is the release ownCloud 11's compose uses and the top of the MariaDB range ownCloud supports (10.2 to 10.11); a newer major is outside it. MARIADB_AUTO_UPGRADE=1, also from ownCloud's compose, runs mariadb-upgrade when the server version changes. A MariaDB data directory cannot move back to an older major, so going down a version means a dump and restore into an empty volume, not an image change. Back up db-data before changing the tag.

redis:7 is the version ownCloud's compose uses.

ownCloud 11 runs on PHP 8. Apps installed into /mnt/data/apps from the marketplace under 10.x were built for PHP 7, so they are removed or replaced with PHP 8 versions before moving a 10.x install to 11.