Unbounded logs eat the disk: cap with size and file count so old pages get torn out.

Docker's default json-file logging driver keeps every line indefinitely, so a chatty service slowly consumes the host's disk. The fix lives in the logging options: set a maximum file size and a maximum number of files, and Docker rotates and discards the oldest. Restart policies and healthchecks answer different questions.

Read it once, then a question tests whether the trick stuck.