How do you view container logs in Docker?
In Docker, container logs are viewed using the docker logs command. It streams or displays the stdout and stderr output of a container. Docker provides rich options to filter logs by time, follow live output, show timestamps, and limit the number of lines — making it the primary tool for debugging and monitoring containerized applications.
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Docker captures everything written to stdout and stderr as container logs
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Logs from files inside the container are NOT captured by docker logs
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The default logging driver is json-file — stores logs as JSON on the host
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docker logs works for both running and stopped containers
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Logs persist until the container is removed or logs are rotated
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Container name or container ID can be used interchangeably
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docker logs <container> — show all logs
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docker logs -f <container> — follow/stream live logs
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docker logs -t <container> — show logs with timestamps
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docker logs --tail N <container> — show last N lines only
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docker logs --since Xm <container> — logs from last X minutes/hours
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docker logs --until <time> — logs before a specific time
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docker logs -tf --tail 100 — most useful debug combo
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docker logs only captures stdout and stderr — app must log to these streams
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docker logs -f is the go-to command for real-time debugging of live containers
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Pipe docker logs to grep for powerful filtering — docker has no built-in search
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Use --since and --until to narrow logs to a specific incident time window
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Configure log rotation with max-size and max-file to prevent disk exhaustion
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docker logs does NOT work with non json-file drivers like fluentd or awslogs
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In production, ship logs to a centralized system — ELK Stack, CloudWatch, Datadog, Loki