How to solve “Internal Server Error” when logging into CubeBackup, after recreating a docker container with “docker-compose up”

You may encounter this error if you have used the web console to upgrade CubeBackup to the latest version (for example, v4.7), but later created a new docker container from the same docker-compose.yml file using the command:

docker-compose up

Internal Server Error

This happens because a number of changes were made to where CubeBackup stores certain files, beginning with version 4.7. If you use docker-compose up after upgrading, it will replace your upgraded version of CubeBackup with an older image, which will be unable to handle the new location of configuration files and altered SQLite databases.

Fortunately, there is a simple solution. Update the docker image to the latest version before creating the new container. For example:

docker-compose pull
docker-compose down
docker-compose up -d --force-recreate