What are the most common instructions in a dockerfile

When encountering Docker problems, you should first locate the problem, which is problems such as image construction, container operation or network configuration, and then follow the steps to check. 1. Check the container log (dockerlogs or docker-composelogs) to obtain error information; 2. Check the container status (dockerps) and resource usage (dockerstats) to determine whether there is an exception due to insufficient memory or port problems; 3. Enter the inside of the container (dockerexec) to verify the path, permissions and dependencies; 4. Review whether there are configuration errors in the Dockerfile and compose files, such as environment variable spelling or volume mount path problems, and recommend that cleanbuild avoid cache dryness

The main difference between Docker and traditional virtualization lies in the processing and resource usage of the operating system layer. 1. Docker containers share the host OS kernel, which is lighter, faster startup, and more resource efficiency; 2. Each instance of a traditional VM runs a full OS, occupying more space and resources; 3. The container usually starts in a few seconds, and the VM may take several minutes; 4. The container depends on namespace and cgroups to achieve isolation, while the VM obtains stronger isolation through hypervisor simulation hardware; 5. Docker has better portability, ensuring that applications run consistently in different environments, suitable for microservices and cloud environment deployment.

When Nginx experiences a "Toomyopenfiles" error, it is usually because the system or process has reached the file descriptor limit. Solutions include: 1. Increase the soft and hard limits of Linux system, set the relevant parameters of nginx or run users in /etc/security/limits.conf; 2. Adjust the worker_connections value of Nginx to adapt to expected traffic and ensure the overloaded configuration; 3. Increase the upper limit of system-level file descriptors fs.file-max, edit /etc/sysctl.conf and apply changes; 4. Optimize log and resource usage, and reduce unnecessary file handle usage, such as using open_l

1. The first choice for the Laravel MySQL Vue/React combination in the PHP development question and answer community is the first choice for Laravel MySQL Vue/React combination, due to its maturity in the ecosystem and high development efficiency; 2. High performance requires dependence on cache (Redis), database optimization, CDN and asynchronous queues; 3. Security must be done with input filtering, CSRF protection, HTTPS, password encryption and permission control; 4. Money optional advertising, member subscription, rewards, commissions, knowledge payment and other models, the core is to match community tone and user needs.

To expose Docker container ports, the host needs to access the container service through port mapping. 1. Use the dockerrun-p[host_port]:[container_port] command to run the container, such as dockerrun-p8080:3000my-web-app; 2. Use the EXPOSE instruction to mark the purpose in the Dockerfile, such as EXPOSE3000, but the port will not be automatically published; 3. Configure the ports segment of the yml file in DockerCompose, such as ports:-"8080:3000"; 4. Use dockerps to check whether the port map is generated after running.

There are three main ways to set environment variables in PHP: 1. Global configuration through php.ini; 2. Passed through a web server (such as SetEnv of Apache or fastcgi_param of Nginx); 3. Use putenv() function in PHP scripts. Among them, php.ini is suitable for global and infrequently changing configurations, web server configuration is suitable for scenarios that need to be isolated, and putenv() is suitable for temporary variables. Persistence policies include configuration files (such as php.ini or web server configuration), .env files are loaded with dotenv library, and dynamic injection of variables in CI/CD processes. Security management sensitive information should be avoided hard-coded, and it is recommended to use.en

The core role of Homebrew in the construction of Mac environment is to simplify software installation and management. 1. Homebrew automatically handles dependencies and encapsulates complex compilation and installation processes into simple commands; 2. Provides a unified software package ecosystem to ensure the standardization of software installation location and configuration; 3. Integrates service management functions, and can easily start and stop services through brewservices; 4. Convenient software upgrade and maintenance, and improves system security and functionality.

To enable PHP containers to support automatic construction, the core lies in configuring the continuous integration (CI) process. 1. Use Dockerfile to define the PHP environment, including basic image, extension installation, dependency management and permission settings; 2. Configure CI/CD tools such as GitLabCI, and define the build, test and deployment stages through the .gitlab-ci.yml file to achieve automatic construction, testing and deployment; 3. Integrate test frameworks such as PHPUnit to ensure that tests are automatically run after code changes; 4. Use automated deployment strategies such as Kubernetes to define deployment configuration through the deployment.yaml file; 5. Optimize Dockerfile and adopt multi-stage construction