{"id":48407,"date":"2025-02-08T08:25:21","date_gmt":"2025-02-08T08:25:21","guid":{"rendered":"https:\/\/www.devopsschool.com\/blog\/?p=48407"},"modified":"2025-07-12T05:38:43","modified_gmt":"2025-07-12T05:38:43","slug":"docker-logs","status":"publish","type":"post","link":"https:\/\/www.devopsschool.com\/blog\/docker-logs\/","title":{"rendered":"Docker commands Guide – docker logs with examples"},"content":{"rendered":"\n

Here\u2019s a complete tutorial<\/strong> on docker logs<\/code>, explaining what it does<\/strong>, a comprehensive list of examples<\/strong>, and use cases<\/strong>.<\/p>\n\n\n\n

\n\n\n\n

What is docker logs<\/code>?<\/strong><\/h2>\n\n\n\n

docker logs<\/code> is a Docker command used to retrieve logs from a running or stopped container<\/strong>. It shows the stdout (standard output)<\/strong> and stderr (standard error)<\/strong> streams of the main process inside the container.<\/p>\n\n\n\n

Key Features:<\/strong><\/h3>\n\n\n\n
    \n
  • Works for both running and stopped containers<\/strong>.<\/li>\n\n\n\n
  • Supports real-time log streaming<\/strong> (--follow<\/code>).<\/li>\n\n\n\n
  • You can filter logs by time<\/strong> or show recent logs<\/strong> (--since<\/code>, --tail<\/code>).<\/li>\n\n\n\n
  • Helps in debugging and monitoring<\/strong> containerized services.<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n

    Basic Syntax<\/strong><\/h2>\n\n\n
    docker<\/span> logs<\/span> [OPTIONS]<\/span> CONTAINER<\/span>\n<\/code><\/span>Code language:<\/span> CSS<\/span> (<\/span>css<\/span>)<\/span><\/small><\/pre>\n\n\n
    Common Options:<\/strong><\/h3>\n\n\n\n
      \n
    • -f<\/code>, --follow<\/code>: Stream real-time logs.<\/li>\n\n\n\n
    • --since<\/code>: Show logs since a specific timestamp (--since 10m<\/code> for last 10 minutes).<\/li>\n\n\n\n
    • --tail<\/code>: Show only the last n<\/strong> lines (--tail 50<\/code>).<\/li>\n\n\n\n
    • -t<\/code>, --timestamps<\/code>: Show timestamps for each log line.<\/li>\n\n\n\n
    • --details<\/code>: Show additional information provided by the container (if available).<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n
      Examples of docker logs<\/code><\/strong><\/h2>\n\n\n\n
      1. Show Logs from a Running Container<\/strong><\/h3>\n\n\n
      docker logs my_container\n<\/code><\/span><\/pre>\n\n\n
      This displays all logs from my_container<\/code>.<\/p>\n\n\n\n
      \n\n\n\n
      2. Follow Logs in Real-Time<\/strong><\/h3>\n\n\n
      docker logs -f my_container\n<\/code><\/span><\/pre>\n\n\n
      This streams the logs in real-time. New log entries appear as they are written.<\/p>\n\n\n\n
      \n\n\n\n
      3. Show Logs with Timestamps<\/strong><\/h3>\n\n\n
      docker logs -t my_container\n<\/code><\/span><\/pre>\n\n\n
      This displays logs with timestamps, useful for tracking when each event occurred.<\/p>\n\n\n\n
      \n\n\n\n
      4. Show the Last 50 Lines of Logs<\/strong><\/h3>\n\n\n
      docker logs --tail 50 my_container\n<\/code><\/span><\/pre>\n\n\n
      This shows only the most recent 50 lines of logs.<\/p>\n\n\n\n
      \n\n\n\n
      5. Show Logs Since a Specific Time<\/strong><\/h3>\n\n\n
      docker<\/span> logs<\/span> --since<\/span> \"2023-02-07T12<\/span>:00<\/span>:00\"<\/span> my_container<\/span>\n<\/code><\/span>Code language:<\/span> CSS<\/span> (<\/span>css<\/span>)<\/span><\/small><\/pre>\n\n\n
      This displays logs generated after 12:00 PM<\/code> on February 7, 2023.<\/p>\n\n\n\n
      \n\n\n\n
      6. Show Logs from the Last 10 Minutes<\/strong><\/h3>\n\n\n
      docker logs --since 10m my_container\n<\/code><\/span><\/pre>\n\n\n
      This shows logs generated in the last 10 minutes.<\/p>\n\n\n\n
      \n\n\n\n
      7. Combine Options: Follow Logs with a Time Filter<\/strong><\/h3>\n\n\n
      docker logs -f --since 5m my_container\n<\/code><\/span><\/pre>\n\n\n
      This streams real-time logs and includes logs from the last 5 minutes.<\/p>\n\n\n\n
      \n\n\n\n
      8. View Logs from a Stopped Container<\/strong><\/h3>\n\n\n
      docker logs my_stopped_container\n<\/code><\/span><\/pre>\n\n\n
      You can still retrieve logs from a container even after it has stopped.<\/p>\n\n\n\n
      \n\n\n\n
      9. Use docker logs<\/code> in a Script<\/strong><\/h3>\n\n\n
      #!\/bin\/bash<\/span>\ndocker logs --tail 100<\/span> my_app > logs.txt\necho<\/span> \"Logs saved to logs.txt\"<\/span>\n<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
      This script saves the last 100 lines of logs from my_app<\/code> to logs.txt<\/code>.<\/p>\n\n\n\n
      \n\n\n\n
      10. Filter Logs from a Specific Service in Docker Compose<\/strong><\/h3>\n\n\n
      docker-compose logs my_service\n<\/code><\/span><\/pre>\n\n\n
      This displays logs for a specific service (my_service<\/code>) in a Docker Compose<\/strong> setup.<\/p>\n\n\n\n
      \n\n\n\n
      Use Cases for docker logs<\/code><\/strong><\/h2>\n\n\n\n
      1. Debugging Application Issues<\/strong><\/h3>\n\n\n\n
        \n
      • View logs to identify errors or crashes.<\/li>\n\n\n\n
      • Example: Check logs for a web server (nginx<\/code>) to find why it\u2019s returning 500 errors.<\/li>\n<\/ul>\n\n\n\n
        2. Monitoring Real-Time Activity<\/strong><\/h3>\n\n\n\n
          \n
        • Stream logs in real-time to monitor container activity.<\/li>\n\n\n\n
        • Example: Watch real-time logs from a Node.js<\/strong> application to see incoming requests.<\/li>\n<\/ul>\n\n\n\n
          3. Tracking Application Performance<\/strong><\/h3>\n\n\n\n
            \n
          • Use timestamps to analyze performance over time.<\/li>\n\n\n\n
          • Example: Measure how long certain tasks take in a background worker container.<\/li>\n<\/ul>\n\n\n\n
            4. Security and Auditing<\/strong><\/h3>\n\n\n\n
              \n
            • Review logs for security incidents<\/strong> or unauthorized access attempts.<\/li>\n\n\n\n
            • Example: Check logs from a MySQL<\/strong> container for failed login attempts.<\/li>\n<\/ul>\n\n\n\n
              5. Log Analysis for Business Insights<\/strong><\/h3>\n\n\n\n
                \n
              • Extract and analyze logs to gain insights into user behavior<\/strong> or system performance<\/strong>.<\/li>\n\n\n\n
              • Example: Analyze web server logs to track page visits.<\/li>\n<\/ul>\n\n\n\n
                6. CI\/CD Pipelines and Testing<\/strong><\/h3>\n\n\n\n
                  \n
                • Use logs to debug failed tests or builds in CI\/CD pipelines<\/strong>.<\/li>\n\n\n\n
                • Example: Check logs from a test runner container<\/strong> to identify why tests failed.<\/li>\n<\/ul>\n\n\n\n
                  \n\n\n\n
                  List of Common docker logs<\/code> Commands<\/strong><\/h2>\n\n\n\n
                  Command<\/strong><\/th>Description<\/strong><\/th><\/tr><\/thead>
                  docker logs my_container<\/code><\/td>Show all logs from the container<\/td><\/tr>
                  docker logs -f my_container<\/code><\/td>Stream logs in real-time<\/td><\/tr>
                  docker logs -t my_container<\/code><\/td>Show logs with timestamps<\/td><\/tr>
                  docker logs --tail 100 my_container<\/code><\/td>Show the last 100 lines of logs<\/td><\/tr>
                  docker logs --since \"2023-02-07T12:00:00\" my_container<\/code><\/td>Show logs since a specific time<\/td><\/tr>
                  docker logs --since 10m my_container<\/code><\/td>Show logs from the last 10 minutes<\/td><\/tr>
                  docker logs -f --since 5m my_container<\/code><\/td>Stream logs in real-time from the last 5 minutes<\/td><\/tr>
                  docker logs my_stopped_container<\/code><\/td>View logs from a stopped container<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
                  \n\n\n\n
                  Best Practices for Using docker logs<\/code>:<\/strong><\/h2>\n\n\n\n
                    \n
                  1. Use --tail<\/code> to avoid overwhelming output<\/strong>, especially for large logs.<\/li>\n\n\n\n
                  2. Stream logs in real-time (-f<\/code>)<\/strong> when monitoring services.<\/li>\n\n\n\n
                  3. Combine with --since<\/code> and --timestamps<\/code><\/strong> for accurate debugging.<\/li>\n\n\n\n
                  4. Centralize logs<\/strong> using tools like ELK (Elasticsearch, Logstash, Kibana)<\/strong> or Promtail\/Loki\/Grafana<\/strong> for better management and searchability.<\/li>\n\n\n\n
                  5. Rotate logs regularly<\/strong> to avoid disk space issues (log-opts<\/code> can help).<\/li>\n<\/ol>\n\n\n\n
                    \n\n\n\n
                    Common Errors and Solutions<\/strong><\/h2>\n\n\n\n
                      \n
                    1. “No such container”<\/strong>
                      \u2192 Ensure the container exists and is running\/stopped. Use docker ps -a<\/code> to verify.<\/li>\n\n\n\n
                    2. “Container is not writing logs”<\/strong>
                      \u2192 Check the container\u2019s logging driver (docker inspect<\/code>) to ensure it\u2019s set to json-file<\/code> or another supported driver.<\/li>\n\n\n\n
                    3. Logs are too large<\/strong>
                      \u2192 Use --tail<\/code> or --since<\/code> to filter logs and reduce output size. Consider enabling log rotation<\/strong>.<\/li>\n<\/ol>\n\n\n\n
                      \n\n\n\n
                      Combining docker logs<\/code> with Other Commands<\/strong><\/h2>\n\n\n\n
                      Check Logs and Restart a Container<\/strong><\/h3>\n\n\n
                      docker logs my_app\ndocker restart my_app\n<\/code><\/span><\/pre>\n\n\n
                      Monitor Logs and Check Resource Usage<\/strong><\/h3>\n\n\n
                      docker logs -f my_app &\ndocker stats my_app\n<\/code><\/span><\/pre>\n\n\n
                      \n\n\n\n
                      <\/p>\n","protected":false},"excerpt":{"rendered":"
                      Here\u2019s a complete tutorial on docker logs, explaining what it does, a comprehensive list of examples, and use cases. What is docker logs? docker logs is a Docker command used… <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_joinchat":[],"footnotes":""},"categories":[4862],"tags":[],"class_list":["post-48407","post","type-post","status-publish","format-standard","hentry","category-docker"],"_links":{"self":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/48407","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/comments?post=48407"}],"version-history":[{"count":2,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/48407\/revisions"}],"predecessor-version":[{"id":48409,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/48407\/revisions\/48409"}],"wp:attachment":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media?parent=48407"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/categories?post=48407"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/tags?post=48407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}