This article explains the concepts, working principles, and system parameters of Linux buffers and cache, compares their roles in read/write operations, and provides practical vmstat and dd command examples to illustrate how they affect memory usage and I/O performance.
This article provides a comprehensive, step‑by‑step guide on using the low‑level dd tool to back up and restore an Ubuntu system disk, covering prerequisites, preparation, command examples, optional compression, feasibility analysis, precautions, and a concise conclusion.
This guide explains how to use the low‑level dd command to create exact backups of an Ubuntu system disk, covering required hardware, preparation steps, precise dd commands for disk‑to‑disk and disk‑to‑image copying, optional compression, restoration procedures, advantages, limitations, and safety precautions.
When a small 2 CPU / 2 GB Alibaba Cloud instance runs Java, Nginx, MySQL, and Redis, memory quickly exhausts; this guide shows how to create and configure a swap file, set appropriate permissions, enable it at boot, and tune the swappiness parameter to mitigate out‑of‑memory failures.
This guide explains how to use the dd command to clone an Ubuntu system disk to another drive or an image file, covering prerequisites, preparation steps, backup and restore commands, optional compression, advantages, drawbacks, use cases, and important precautions.
Learn how to harness the versatile Linux dd command for copying files, creating and restoring disk images, generating random data, adjusting block sizes, showing progress, skipping or truncating data, and performing on‑the‑fly conversions, with clear examples and practical tips for safe usage.
This guide explains how to use the stress and dd utilities together with a custom Bash script to artificially consume CPU, memory, and disk resources on idle cloud servers, helping you demonstrate load without affecting production workloads.
This guide explains how to use the stress and dd utilities together with a custom shell script to artificially consume CPU, memory, and disk resources on idle cloud servers, helping avoid budget cuts by keeping resource utilization high for a configurable period.
Learn practical Linux commands—dd, truncate, and fallocate—to generate large files of specific sizes for testing or troubleshooting, with clear examples and tips on choosing the fastest method.
When you need a file of a specific size for testing or troubleshooting on Linux, you can use the dd, truncate, or fallocate commands to generate large files efficiently without manually writing data.
This article explains why backing up a Linux system is essential and walks you through four reliable disk‑cloning tools—dd, Partimage, Partclone, and Clonezilla—detailing installation, command usage, and best‑practice tips for creating recoverable disk images.
This guide shows how to use Linux's tmpfs file system together with simple commands like mount, dd, and taskset to allocate large amounts of RAM, simulate OOM conditions, and even target specific NUMA nodes without writing custom code.
This guide explains why regular backups are essential on Linux and provides step‑by‑step commands for creating full system archives with tar, cloning disks with dd, synchronizing files with rsync, and performing image‑based restores on new machines.
This guide explains how to safely back up and restore a Linux system using tar archives, rsync synchronization, dd cloning, and full-disk imaging, covering command syntax, exclusion of volatile directories, preparation steps, and post‑restore configuration to ensure a reliable recovery.
This guide explains how to back up an entire Linux system or create a disk image using tar, rsync, and dd commands, covering exclusion of system directories, restoration steps, and special considerations for migrating to a new host.
This guide explains why removing a file with rm doesn't always release space, demonstrates creating a large test file, shows how open file handles keep space occupied, and provides commands to identify and release such hidden usage.
This article explains how Linux file deletion works, why space may not be released when a file is removed, and shows practical commands and a C example to illustrate inode reference counting, using tools like df, dd, lsof, and proper file‑descriptor handling.
This article outlines five typical cloud‑host file‑loss scenarios—including tmpfs data loss after reboot, accidental rm commands, and disk damage from fio or dd—explains their causes, and provides practical prevention and recovery recommendations for operations engineers.
Learn how to protect critical data on Linux by using the powerful dd command, with six detailed examples covering full-disk cloning, image creation, partition backup, floppy and CD ISO imaging, and essential options like conv=noerror and bs for reliable, low-level backups.
This article explains why using uppercase YYYY or DD in Java date‑format patterns can produce incorrect results around year boundaries, demonstrates the bugs with concrete code examples, and clarifies the correct usage of lowercase yyyy and dd for calendar dates.
This article describes a real‑world Ceph storage incident caused by disk bad sectors, analyzes its impact, and presents two practical recovery methods—full disk copy with dd+nc and skipping the faulty sector during service start—along with detailed commands and post‑recovery steps.
This article explains how different dd command variations affect disk write‑cache handling and why using the conv=fdatasync option yields the most reliable measurement of actual disk write performance.
