Linux

rsync is one of the most useful tools in a sysadmin’s kit. It copies and synchronizes files and directories locally or over SSH, and only transfers the parts of files that have changed – making it far more efficient than a plain cp or scp for repeated transfers. These are the commands you’ll reach for most often. Common Flags The -avP combination is a solid default for most operations: -a (archive) – preserves permissions, ownership, symlinks, and timestamps -v (verbose) – shows what’s being transferred in real time -P (progress + partial) – displays a progress bar and resumes interrupted transfers 1. Copy a Single File rsync -avP /path/to/local/file.zip user@remote_server:/path/to/remote/directory/ 2. Copy a Directory The trailing slash matters here: ...

If you use Windows Subsystem for Linux (WSL2), you may have noticed a large file on your system drive: C:\Users\<YourUser>\AppData\Local\Packages\<YourDistroFolder>\LocalState\ext4.vhdx This is a virtual hard disk that stores the entire Linux filesystem. It expands automatically as you install packages and create files, but it does not shrink automatically when files are deleted. Over time, this can leave you with a multi-gigabyte file containing mostly unused space. Here’s how to safely compact it and reclaim that space. ...

Search for BCM4332 and Linux and you’ll find years of forum threads with the same discouraging pattern: someone asks for help, someone replies “that chip doesn’t work on Linux anymore,” and the thread dies. That conclusion is wrong, and it’s been wrong every time someone wrote it. The BCM4332 chip works on modern Linux. Ubuntu 22.04, Ubuntu 24.04, Linux Mint, Debian 12 — all of them. But it requires steps that the default package manager doesn’t take automatically, and if you skip any of them, you’ll end up with a chip that either doesn’t appear at all, or worse — works right now but vanishes silently after the next reboot. ...

If you manage servers that use OpenVZ (Virtuozzo), chances are you’ll spend a lot of time working with vzctl to start, stop, and maintain containers (CTs). While modern virtualization has largely moved on to KVM, Docker, and LXC, plenty of production systems still rely on OpenVZ — especially for legacy applications. This is a quick reference of essential vzctl commands for day-to-day container administration. List All Containers vzlist -a Displays all containers, including stopped ones. ...