Articles by Dejan Panovski
Bash Append to File: >>, tee, and Heredoc Examples
Append text to a file in Bash without erasing existing content. Covers >>, echo, printf, tee -a for protected files, and combining files.
500 Internal Server Error: What It Means & How to Fix It
A 500 Internal Server Error means the server encountered an unexpected condition. This guide explains common causes, how to diagnose the problem using log files, and steps to fix it.
How to Change the Hostname in Linux
Change the hostname in Linux with hostnamectl and /etc/hosts. Covers permanent, temporary, cloud-init, and non-systemd methods.
curl POST Request Examples
Send data with curl -d, --json, and -F: POST examples for HTML forms, JSON APIs, file uploads, and reading the body from a file or stdin.
Sudo Command in Linux: Run Commands as Root
The sudo command runs programs as root or another user. This guide covers sudoers setup, root shells, sudoedit, credential caching, and common sudo options.
How to Generate SSH Keys on Linux with ssh-keygen
Generate an SSH key pair on Linux with ssh-keygen, choose between Ed25519 and RSA, and install the public key on a server, a Git host, or a cloud provider.
DNS Record Types Explained: A, AAAA, CNAME, MX, TXT, and More
DNS record types map domains to servers, route email, publish verification data, and control certificate issuance. See zone-file examples and dig queries.
How to Extract tar.xz Files in Linux
Extract .tar.xz and .txz archives in Linux with tar. Covers extracting to a directory, listing contents, decompressing plain .xz files with unxz, and installing software from a tar.xz download.
Initial Server Setup on Ubuntu 26.04
Prepare a new Ubuntu 26.04 server with a sudo user, SSH key authentication, UFW firewall rules, a hostname, timezone settings, and system updates.
Linux cp Command: Copy Files and Directories
The cp command copies files and directories in Linux. This guide covers recursive and archive copies, copying directory contents, overwrite control, and attributes.
How to Set Up Passwordless SSH Login
Set up passwordless SSH login with Ed25519 or RSA key pairs. Copy public keys with ssh-copy-id, use the ssh-agent, and disable password authentication for hardened access.
How to Use sed to Find and Replace Strings in Files
Replace strings in files with sed: run sed -i 's/old/new/g' file. Covers global, case-insensitive, word-boundary, regex, line-range, and recursive replace.
Bash Best Practices: Writing Safer, Cleaner Scripts
Practical Bash best practices for writing safer and more predictable scripts, covering strict mode, quoting, error handling, and everyday patterns.
How to List Groups in Linux
Find which groups a user belongs to in Linux using the groups, id, and getent commands. Includes how to list all groups and group members on the system.
How to Redirect stderr to stdout in Bash
Redirecting stderr and stdout in Bash using 2>&1, &>, and other operators. Covers file descriptors, appending, piping errors, and discarding output with /dev/null.
How to Delete Lines in Vim / Vi
Delete lines in Vim or Vi with dd, :%d, visual mode, or :g/pattern/d. Examples for single lines, ranges, all lines, and pattern-based deletion.
How to Check Your Debian Version: Commands and Release List
Debian 13 (trixie) is the current stable release. Check your version with /etc/os-release, lsb_release, or hostnamectl, plus codenames and support dates.
How to Remove a Symbolic Link (Symlink) in Linux
Remove symbolic links in Linux with rm, unlink, or find. Clean up broken symlinks and avoid the trailing-slash trap that can remove target directory contents.
How to Run a Bash Script in Linux
Run a bash script in Linux with chmod +x, the bash interpreter, or source. Step-by-step examples with common errors and fixes.
sleep Command in Linux: Pause a Bash Script
How to use the sleep command in bash to pause script execution. Examples cover seconds, minutes, sleep infinity, retry loops, countdowns, and background sleeps.
