The rpm and dnf commands let you inspect exactly which files a package installed and find the package that owns a specific file. These queries work on both the host system and inside containers like Toolbox or Distrobox. List Files from an Installed Package rpm -ql package-name This recursively lists all files and directories the…
rsync is a reliable choice for backing up your Linux home directory, especially when dealing with large files and incremental changes. Unlike git (which struggles with files >5GB), rsync efficiently handles large files and only transfers what’s changed on subsequent runs. Basic Backup Command The fundamental syntax is straightforward: rsync -avxP \ /path/to/directory/to/backup \ /path/to/directory/for/storing/backup…
ffmpeg is the de facto tool for desktop recording on Linux. It can capture your X11 or Wayland display and encode directly to MP4, WebM, or other formats without requiring intermediate files. Basic X11 Screen Capture For X11-based desktops (KDE Plasma, XFCE, i3, etc.), use the x11grab input device: ffmpeg -f x11grab -s 1920×1080 -r…
If you don’t already have a key pair, use Ed25519 — it’s faster and more secure than RSA: ssh-keygen -t ed25519 -C “your_email@example.com” For older systems that don’t support Ed25519, RSA with 4096 bits still works: ssh-keygen -t rsa -b 4096 Keys are stored in ~/.ssh/ by default: id_ed25519 (private) and id_ed25519.pub (public) for Ed25519,…
sshfs is the standard tool for mounting remote filesystems over SSH. It’s available in most distribution repositories. Debian/Ubuntu: sudo apt install sshfs RHEL/CentOS/Fedora: sudo dnf install sshfs Alpine: apk add sshfs On some systems you may need to ensure the fuse kernel module is loaded: sudo modprobe fuse Basic Mount Mount a remote directory to…
The mailx (or s-nail on modern distributions) command remains useful for scripted email delivery, particularly when you need to send alerts or notifications automatically. Gmail’s SMTP service works well for this, though it requires TLS authentication and specific configuration. Prerequisites Most Linux distributions include mailx or s-nail by default. On systems using s-nail (Ubuntu 20.04+,…
A Linux box serving as a network gateway needs two network interfaces: eth0: Connected to the local network (LAN) with IP 192.168.0.1 eth1: Connected to the upstream network (Internet) with IP 198.51.100.1 The goal is to allow clients on the 192.168.0.0/16 network to route traffic through this gateway to reach external networks. Enable IP Forwarding…
Guake is a drop-down terminal emulator for GNOME that brings the Quake-style console experience to Linux desktops. When you press a hotkey (F12 by default), a terminal slides down from the top of the screen. Press it again and it retracts. It’s fast, minimal, and designed purely around keyboard efficiency. Installation On Fedora/RHEL-based systems: sudo…
A SOCKS5 proxy tunneled through SSH provides encrypted communication between your client and a remote server. This is useful for bypassing network restrictions, securing connections on untrusted networks, or routing traffic through a trusted server. Basic Setup The simplest approach uses SSH’s dynamic port forwarding with the -D flag: ssh -D 8080 username@sshd_server This creates…
Xen remains in production use (AWS EC2, Citrix Hypervisor), though KVM has become the standard Linux hypervisor. This guide covers automating backups for file-backed Xen virtual machines. The approach adapts to other hypervisors like KVM with minimal modification. Architecture and Prerequisites The backup system assumes: Virtual machines stored in /lhome/xen/ with individual directories per VM…
When you need to start long-running commands while continuing to work in the shell, run them in the background. Bash and other modern shells maintain a job list and allow you to switch jobs between foreground and background execution. Only one job can run in the foreground at a time. Starting a Background Job Append…
Accessing a remote desktop environment on a Linux server securely requires proper tunneling. While SSH X11 forwarding works for single applications, VNC provides a full graphical desktop session. By combining VNC with an SSH tunnel, you encrypt all traffic and can work around firewall restrictions that only allow port 22. Why VNC Over SSH? VNC…
MPlayer is largely unmaintained; mpv is the actively developed fork that handles 95% of these commands with compatible bindings. That said, if you’re still running MPlayer or need legacy support, here’s what you need to know. MPlayer uses a fully configurable keyboard control layer. Most of these shortcuts work in mpv as well, though some…
DNS caching helps reduce lookups but sometimes you need to clear it after DNS changes, certificate updates, or to troubleshoot resolution issues. Modern Linux with systemd-resolved Most contemporary Linux distributions use systemd-resolved as the default DNS resolver. Flush the cache with: sudo systemctl restart systemd-resolved Or use the resolvectl command: sudo resolvectl flush-caches To verify…
When you open a Windows file in Vim (or Neovim), you’ll often see ^M characters at the end of lines. These are carriage returns (\r) from Windows line endings (CRLF), which don’t display properly on Unix-like systems that expect LF-only line endings. Quick Fix The fastest way to remove these characters is with a substitution…
Git and SSH integrate seamlessly for version control infrastructure. An SSH-based Git server works well for small teams where all members are trusted and have administrator-level access to all repositories. This approach is straightforward to deploy, but lacks fine-grained access control. For teams that need role-based repository access or audit trails, consider dedicated tools like…
ISO images are sector-by-sector copies of optical media stored as binary files. They’re useful for archiving DVDs or creating portable copies without keeping physical disks around. On Linux, several tools can accomplish this—dd is the simplest, but modern alternatives offer better features. Using dd to Create an ISO Image The most straightforward approach uses dd:…
Compiz Fusion is a lightweight 3D window manager and compositing system that can replace your standard window manager. While it’s rarely the default choice on modern Fedora installations, it remains available for users who want its visual effects and functionality. Note: Compiz development has slowed significantly. Most Fedora users today use Wayland-based desktops (GNOME, KDE…
The default number of loop devices on most Linux systems is 8, which is often insufficient for scenarios like running multiple virtual machines with loop device-backed storage, containerized environments, or disk image management. If you need more than the default allocation, you’ll need to increase max_loop. First, check your current loop device count: losetup -f…
To connect to HKUST’s sMobileNet wireless network via NetworkManager, you’ll need to configure WPA2 Enterprise authentication with PEAP. This guide covers the required settings. Network Settings Configure the following parameters in NetworkManager: Basic Settings: SSID: sMobileNet Wireless security: WPA & WPA2 Enterprise Authentication method: Protected EAP (PEAP) Authentication Details: Anonymous identity: (leave empty) PEAP version:…