When managing cron tasks, you need to pay attention to paths, environment variables and log processing. 1. Use absolute paths to avoid commands or scripts not being found due to different execution environments; 2. Explicitly declare environment variables, such as PATH and HOME, to ensure that the variables dependent on the script are available; 3. Redirect output to log files to facilitate troubleshooting; 4. Use crontab-e to edit tasks to ensure that the syntax is correct and takes effect automatically. Mastering these four key points can effectively avoid common problems.

The steps to add a new hard disk to the Linux system are as follows: 1. Confirm that the hard disk is recognized and use lsblk or fdisk-l to check; 2. Use fdisk or parted partitions, such as fdisk/dev/sdb and create and save; 3. Format the partition to a file system, such as mkfs.ext4/dev/sdb1; 4. Use the mount command for temporary mounts, such as mount/dev/sdb1/mnt/data; 5. Modify /etc/fstab to achieve automatic mount on the computer, and test the mount first to ensure correctness. Be sure to confirm data security before operation to avoid hardware connection problems.

In Linux systems, network interface information can be viewed through ip, ifconfig and nmcli commands. 1. Use iplinkshow to list all network interfaces, add up parameters to display only active interfaces, and use ipaddr or ipad to view IP allocation status; 2. Use ifconfig-a to be suitable for old systems, and you can view all interfaces. Some new systems need to install net-tools package; 3. Use nmclidevicestatus to be suitable for systems managed by NetworkManager, which can view interface status and connection details, and supports filtering and query. Select the appropriate command according to the system environment to complete the network information viewing.

The top command can view the Linux system resource usage in real time. 1. Enter top through the terminal to open the interface, and the top displays the system running status summary, including load, task number, CPU and memory usage; 2. The process list is sorted by CPU usage by default, which can identify highly occupant processes; 3. Shortcut keys such as P (CPU sort), M (memory sort), k (end process), r (adjust priority), and 1 (multi-core details) improve operation efficiency; 4. Use top-b-n1 to save output to a file; 5. Adding the -u parameter to filter specific user processes. Mastering these key points can quickly locate performance issues.

Running Ansibleplaybook requires first ensuring that the structure is correct and the environment is prepared. 1. Write a playbook file, including hosts, tasks, etc.; 2. Ensure that the target host is in the inventory and can be connected through SSH, and can be tested by ansibleping module; 3. Use the ansible-playbook command to run, and you can add -i to specify the inventory path; 4. You can use -v, --check, --limit, --tags and other parameters to debug or control execution; 5. Pay attention to common error points such as YAML indentation, module parameters, permissions and inventory content. Using --check and -v will help troubleshoot errors

The management software RAID array can be maintained through several critical steps. First, use the mdadm command to view the status or view /proc/mdstat; secondly, replace the hard disk and remove the bad disk and add a new disk and rebuild the array; thirdly, expand the capacity to be suitable for RAID types that support capacity expansion by adding disks and adjusting the file system; finally configure daily monitoring to automatically detect abnormalities through scripts and email notifications to ensure the stable operation of the array.

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 key to writing ChefRecipes is to have clear structure, single responsibilities, and strong maintainability. ChefRecipes is a declarative configuration that defines the system status through resources, such as package installation software, service control services, file/template management files, and user management users. 1. Each Recipe should only be responsible for one task, such as installing Nginx and configuring the site; 2. Use include_recipe to control the dependency order, use notifies and subscribes to achieve event-driven; 3. Improve readability, use meaningful variable names, unified indentation, avoid hard coding, and prioritize the use of attributes over direct values. Following these principles can improve R