Migrating your app to Kubernetes: what to do with files?

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While building a CI/CD pipeline with Kubernetes, you may face an issue when requirements of the new infrastructure and an application that is being migrated to it are incompatible. Specifically, it is essential to build a single image when building an application*. It will be used in all environments and clusters of the project.

* This principle underlies the correct approach (according to Google, Red Hat and many others) to managing containers.

Yet there are situations when some site uses a ready-made framework that imposes various restrictions on its future operation. You can easily find a way around this in the “standard environment,” but in Kubernetes, things are much more complicated, especially when you encounter this problem for the first time. Sure, an inventive mind may find infrastructure workarounds that may seem obvious and compelling at first glance… However, you always have to remember that you ought to implement architectural solutions in most cases.

Let’s examine popular workarounds for storing files that may have unintended consequences during the cluster operation. We will also provide more appropriate approach to each of them.

Please, read the rest here.