Docker Disk Usage Persists After Pruning Containers, Due to Persistent Volumes

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A Linux user found their disk still full after removing old containers and images with Docker cleanup commands. Investigation with du showed that the Docker directory under /var/lib was consuming about 79 GB, the largest share of disk usage on the machine. The author used docker system df to examine storage across images, containers, volumes, and build cache. The main takeaway is that persistent volumes hold much of this space and are not removed by ordinary pruning. The article explains how to locate and clean up unused resources without deleting data belonging to active containers.

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ProgrammingDEV Community ·

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