An upgrade of Deckhouse Code installs a new version over the current one: the configuration and the data are kept, and the configuration run and the database migrations start automatically. The rules below apply to every installation type.
Version order
Upgrade sequentially, without skipping major versions: the database migrations are designed for the transition from the previous major version. If several major releases lie between the current and the target version, install them one by one and wait for the background migrations to finish between the steps. Ask the vendor for the upgrade path for your pair of versions when you obtain the new version.
Background migrations
An upgrade applies the main database migrations and does not wait for the background ones: they keep running on the instance that is already serving users. All background migrations must finish before the next upgrade, otherwise the upgrade stops with an error.
To check the state of the migrations, select “Admin” in the top right corner, then go to “Monitoring” → “Background migrations” in the left pane. The “Queued” and “Finalizing” tabs must have no jobs left and the “Failed” tab must be empty: every migration is in the “Finished” status. On a typical instance this takes minutes, and longer on large amounts of data.
Deckhouse Kubernetes Platform module
In the module delivery, the upgrade is started by the platform, and with backup creation before an update enabled, the operator updates the remaining components after the backup job has finished successfully. The order is described in the Automatic backup creation before module updates section of the module documentation.