Upgrade

This page is for the person who runs the server. It covers moving to a new build and going back from one.

Before you upgrade

Run a backup and verify it. See Backup and restore. An upgrade with no verified backup has no way back.

Upgrade

Build the new image and start it, then wait for the readiness answer. The application container applies the migrations before it serves, so a build whose migrations have not run never reports ready.

A migration moves forward only. If one fails, the container exits and the restart policy repeats the attempt, and the application stays unready while that happens. Read the application container log, fix the cause, and the next attempt completes.

Going back

There is no downward migration. To go back to the prior build, restore the verified pre-upgrade database and attachment set into an empty target, then start the prior build against it.

Do not copy a database without its referenced attachments, and do not copy attachments without the matching database snapshot. The two halves are one backup. See Backup and restore.