Network security is the cornerstone of operations and maintenance, and mastering iptables and firewalld is an essential skill for every Linux administrator. This article will take you deep into the core principles and practical techniques of these two major firewall tools! 1. Introduction to iptables iptables is a command-line tool for managing firewall rules in … Read more
1. Basic Commands uname -m # Display the machine's processor architecture uname -r # Display the currently used kernel version dmidecode -q # Display hardware system components (SMBIOS / DMI) hdparm -i /dev/hda # List a disk's architectural features hdparm -tT /dev/sda # Perform a test read operation on the disk arch # Display the … Read more
1. Delete expired files in Linux find /u01/dsg/supersync/s01/ds/xdt/ -type f -name “*.xdt” -mtime +3 -delete 2. Delete expired files and log the deletions find /u01/dsg/supersync/s01/ds/xdt/ -name “*.xdt” -mtime +3 -printf “Deleting %p\n” -delete | tee deletion.log 3. Step-by-step logging service nginx start 1> /var/log/nginx/start.log 2> /var/log/nginx/start_errors.log Normal logs are recorded in start.log, and error logs … Read more
This article compiles the top 50 questions frequently encountered in Linux system operation and maintenance interviews. Whether you are a beginner entering the IT industry or an experienced operations personnel aiming for promotion, these questions will provide you with comprehensive knowledge review and practical simulation, helping you stand out in interviews, successfully secure your desired … Read more
IntroductionLow-power IoT solutions enable devices to operate remotely for extended periods without direct power supply. Recently, the market demand for low-power Linux IoT devices is expected to continue growing, and the i.MX 91 is well-suited for this market segment. The NXP i.MX 91 processor is an application processor based on the Arm Cortex-A55 core, designed … Read more
In Linux operations, mastering key commands can significantly enhance troubleshooting and system management efficiency. Whether it’s server lag, network anomalies, or log analysis and performance optimization, the right commands can help you quickly identify and resolve issues. This article compiles 20 of the most practical Linux commands, covering system monitoring, network diagnostics, log analysis, and … Read more
01 About the Three Musketeers of Linux grep: Filters keyword information data. Mainly used to search for data within text. sed: Edits text data and modifies the original file content. awk: Filters and extracts data from files, and can format the output. awk can also present the processed data in a more visually appealing way. … Read more
If your server’s memory usage is too high, causing slow performance or crashes, you can try the following Linux command to quickly free up cached memory: # This parameter can be used to instruct the kernel to actively free memory caches, but it will not affect running programs. sync; echo 3 > /proc/sys/vm/drop_caches Command Explanation … Read more
<span>pgrep</span> and <span>grep</span> are two different commands in the Linux system. Although their names are similar, they have significant differences in functionality and usage scenarios. Here are their core differences: <span>pgrep</span> is an acronym that stands for “Process-ID Global Regular Expressions Print”. <span>grep</span> is an acronym for “Global Regular Expressions Print”, meaning global regular expression … Read more
Feeling unwell, I initially thought of skipping this update. However, I happened to meet a security guard who was fiddling with his vegetable pot. After chatting for a while and seeing him remove some plants he deemed worthless, I took one to plant on the third-floor flower bed. Even if it only lasts three seasons, … Read more