Docker – Update Docker Container Without Dataloss

docker

I've docker-pulled an image, then ran a named container. How can I update that named container to the latest image?

And it would be perfect to not loos any data and not have to setup data directories and initialize and fill them with old data (just using current volumes).

Env: docker, Ubuntu 14.04

Best Answer

How can I update that named container to the latest image?

That's not how docker is intended to be used.

Each image (and containers based on them) should be stateless. If the processes running in each container need to store state somewhere, it should be somewhere outside of that container. That could be in a RDBMS, a volume mount from the host filesystem, a docker volume, etc.

If you really want to do what you're asking, it's likely that you should not be using docker, as you will be guaranteed to spend more time making the tool do things that it's not meant to do than is appropriate.


After discussion in comments below, it was clarified that all you're asking is: does data in host-volume mounts get deleted along with containers. The answer to that is: no it does not.