{"id":764,"date":"2024-07-22T20:40:36","date_gmt":"2024-07-22T20:40:36","guid":{"rendered":"https:\/\/dockerpros.com\/?post_type=glossary&p=764"},"modified":"2024-07-22T20:55:30","modified_gmt":"2024-07-22T20:55:30","slug":"politicas-de-reinicio-de-dockerlas-politicas-de-reinicio-de-docker-controlan-si-tus-contenedores-se-reinician-automaticamente-cuando-se-caen-o-cuando-docker-se-reinicia-las-politicas-de-reinicio-de","status":"publish","type":"glossary","link":"https:\/\/dockerpros.com\/es\/wiki\/docker-restart-policies\/","title":{"rendered":"Pol\u00edticas de reinicio de Docker\n\nLas pol\u00edticas de reinicio de Docker controlan si tus contenedores se reinician autom\u00e1ticamente cuando salen por cualquier motivo. Cuando se implementa un contenedor en un cl\u00faster, Docker asigna una pol\u00edtica de reinicio al contenedor. La pol\u00edtica de reinicio garantiza que los contenedores se comporten de la manera esperada. Por ejemplo, un contenedor con una pol\u00edtica de reinicio de nunca se detendr\u00e1 cuando salga. Por otro lado, un contenedor con una pol\u00edtica de reinicio de siempre se reiniciar\u00e1 sin importar el estado de salida.\n\nLas pol\u00edticas de reinicio de Docker son diferentes de los comandos de ejecuci\u00f3n como dockerd --live-restore. La opci\u00f3n --live-restore permite que la conexi\u00f3n del cliente Docker se mantenga durante el mantenimiento del demonio Docker, aunque los contenedores se detengan.\n\nPara configurar la pol\u00edtica de reinicio de un contenedor Docker, utiliza la opci\u00f3n --restart. La opci\u00f3n --restart se puede utilizar de las siguientes maneras:\n\n- no: No reiniciar el contenedor autom\u00e1ticamente. Esta es la pol\u00edtica de reinicio predeterminada.\n- on-failure: Reiniciar el contenedor si falla debido a un error. Si el contenedor se detiene por cualquier otra raz\u00f3n, no se reiniciar\u00e1.\n- always: Reiniciar siempre el contenedor sin importar el estado de salida.\n- unless-stopped: Reiniciar siempre el contenedor sin importar el estado de salida, a menos que el contenedor se detenga manualmente o Docker se detenga.\n\nVeamos un ejemplo de c\u00f3mo utilizar la opci\u00f3n --restart. Para crear un contenedor con una pol\u00edtica de reinicio de always, utiliza el siguiente comando:\n\n```\n$ docker run -d --restart=always nginx\n```\n\nEn este ejemplo, el contenedor nginx se reiniciar\u00e1 autom\u00e1ticamente si se detiene por cualquier motivo.\n\nPara crear un contenedor con una pol\u00edtica de reinicio de on-failure, utiliza el siguiente comando:\n\n```\n$ docker run -d --restart=on-failure:5 nginx\n```\n\nEn este ejemplo, el contenedor nginx se reiniciar\u00e1 autom\u00e1ticamente si se detiene debido a un error. Sin embargo, si el contenedor se detiene por cualquier otra raz\u00f3n, no se reiniciar\u00e1. El n\u00famero 5 especifica el n\u00famero m\u00e1ximo de intentos de reinicio.\n\nPara ver la pol\u00edtica de reinicio de un contenedor, utiliza el siguiente comando:\n\n```\n$ docker inspect --format \"{{.HostConfig.RestartPolicy}}\" \n```\n\nEn este ejemplo, reemplaza con el ID del contenedor que deseas inspeccionar.\n\nPara actualizar la pol\u00edtica de reinicio de un contenedor, utiliza el siguiente comando:\n\n```\n$ docker update --restart= \n```\n\nEn este ejemplo, reemplaza con la pol\u00edtica de reinicio que deseas establecer y con el ID del contenedor que deseas actualizar.\n\nLas pol\u00edticas de reinicio de Docker son una herramienta poderosa para garantizar que tus contenedores se comporten de la manera esperada. Al utilizar las pol\u00edticas de reinicio adecuadas, puedes asegurarte de que tus contenedores se reinicien autom\u00e1ticamente cuando sea necesario, lo que puede ayudar a mejorar la disponibilidad y la confiabilidad de tus aplicaciones."},"content":{"rendered":"

Understanding Docker Restart Policies: Ensuring Resilience in Containerized Applications<\/h1>\n

Docker Restart Policies are a pivotal feature within the Docker ecosystem that govern the behavior of containers in response to failures. These policies enable containers to automatically restart under specified conditions, improving the resiliency and availability of applications deployed in containerized environments. By leveraging Docker Restart Policies, developers and system administrators can ensure that critical services remain operational and recover quickly from unexpected disruptions.<\/p>\n

The Importance of Restart Policies<\/h2>\n

In a microservices architecture, where applications are typically composed of multiple interdependent services, the availability of each component is crucial for overall system health. Containers, while lightweight and efficient, can experience failures due to various reasons such as application bugs, resource constraints, or external system issues. This is where Docker Restart Policies come into play. They not only provide a mechanism for recovery but also contribute to the robustness of deploying applications in production environments.<\/p>\n

Types of Restart Policies<\/h3>\n

Docker offers several restart policies to accommodate different operational needs:<\/p>\n

    \n
  1. \n

    No Restart<\/strong> (--restart=no<\/code>): This is the default policy, which means that if a container<\/a><\/span>Containers are lightweight, portable units that encapsulate software and its dependencies, enabling consistent execution across different environments. They leverage OS-level virtualization for efficiency. More \u00bb<\/a><\/span><\/span><\/span><\/span><\/span> stops, it will not be restarted. This policy is suitable for one-off tasks or containers that are expected to exit without any error.<\/p>\n<\/li>\n

  2. \n

    Always Restart<\/strong> (--restart=always<\/code>): With this policy, Docker will always restart the container<\/a><\/span>Containers are lightweight, portable units that encapsulate software and its dependencies, enabling consistent execution across different environments. They leverage OS-level virtualization for efficiency. More \u00bb<\/a><\/span><\/span><\/span><\/span><\/span> regardless of how it exited\u2014be it due to a failure, a manual stop, or the Docker daemon<\/a><\/span>A daemon is a background process in computing that runs autonomously, performing tasks without user intervention. It typically handles system or application-level functions, enhancing efficiency. More \u00bb<\/a><\/span><\/span><\/span><\/span><\/span> restarting. This is often used for long-running services that need to be highly available.<\/p>\n<\/li>\n

  3. \n

    Unless Stopped<\/strong> (--restart=unless-stopped<\/code>): This policy is similar to always<\/code>, but it will not restart the container<\/a><\/span>Containers are lightweight, portable units that encapsulate software and its dependencies, enabling consistent execution across different environments. They leverage OS-level virtualization for efficiency. More \u00bb<\/a><\/span><\/span><\/span><\/span><\/span> if it was explicitly stopped by the user. It allows for manual control while still providing automatic restarts for crashes or daemon<\/a><\/span>A daemon is a background process in computing that runs autonomously, performing tasks without user intervention. It typically handles system or application-level functions, enhancing efficiency. More \u00bb<\/a><\/span><\/span><\/span><\/span><\/span> restarts.<\/p>\n<\/li>\n

  4. \n

    On Failure<\/strong> (--restart=on-failure[:max-retries]<\/code>): This policy instructs Docker to restart the container<\/a><\/span>Containers are lightweight, portable units that encapsulate software and its dependencies, enabling consistent execution across different environments. They leverage OS-level virtualization for efficiency. More \u00bb<\/a><\/span><\/span><\/span><\/span><\/span> only if it exits with a non-zero exit code, indicating an error. Additionally, it can limit the number of restart attempts using the max-retries<\/code> parameter, which can be beneficial for managing resources and preventing infinite restart loops.<\/p>\n<\/li>\n<\/ol>\n

    Choosing the Right Restart Policy<\/h3>\n

    Selecting the appropriate restart policy is crucial for ensuring the desired behavior of your containers. The choice depends on the application architecture, user expectations, and operational requirements. Here are some guidelines to help you make an informed decision:<\/p>\n