Privzeto so podatki v kontejnerju efemerni — izgubljeni, ko je kontejner odstranjen. Volumes (in bind mount) zagotavljajo trajno shranjevanje podatkov, ki preživi kontejnerje, kar je bistvenega pomena za baze podatkov in vse podatke, ki morajo preživeti ponovni zagon/odstranitev kontejnerja.
Problem: kontejnerji so efemerni
A container's writable layer is DELETED when the container is removed:
→ data written inside the container (e.g. a database's files) is LOST
→ containers are meant to be disposable/replaceable → don't store important data in them
→ For persistent data, you need storage OUTSIDE the container's lifecycle.
