LinuxTeck - Linux Sysadmins Community - RHEL, CentOS, Ubuntu, Debian & Rocky Linux
92 subscribers
325 photos
2 videos
1 file
466 links
LinuxTeck is a high-quality tutorial site dedicated to beginners, system administrators, developers, and everyone interested in learning about Linux. https://www.linuxteck.com/
Download Telegram
latpak vs Snap vs AppImage

Flatpak, Snap, or AppImage which should you use on Linux?
This guide compares all three package formats, covering security, updates, portability, performance, installation, and the best use cases for each.
https://www.linuxteck.com/flatpak-vs-snap-vs-appimage/
#LinuxTeck #Linux #Flatpak #Snap #AppImage #OpenSource
Quick Linux Tip #34

Question: How fast is my network really? Not just ping - actual throughput.

Try: iperf3 -c 192.168.1.100

Info: iperf3 measures real TCP/UDP throughput. Run iperf3 -s on the server and iperf3 -c <SERVER_IP> on the client.

Examples:
$ iperf3 -s # Server mode (run first)
$ iperf3 -c server -u -b 1G # UDP test at 1 Gbps
$ iperf3 -c server -R # Reverse mode (test download speed)

Note: Install via apt install iperf3. Ensure port 5201 is open. A non-zero Retr column indicates packet loss/congestion.

Follow @LinuxTeck for more #LinuxTips
The 7 Stages of Learning Linux: A Practical Roadmap from Beginner to System Administrator

Learning Linux can feel overwhelming when you're unsure what to learn next.
I put together a practical roadmap that breaks Linux into seven stages, covering fundamentals, system administration, networking, shell scripting, security, and production skills. Each stage includes clear learning goals, projects, and a progress tracker.
I'd appreciate any feedback from experienced Linux users. Is there anything you'd add or change?
https://www.linuxteck.com/7-stages-linux-learning-roadmap/
Quick Linux Tip #35

Question: My SSH key uses old RSA. How do I switch to a modern strong algorithm?

Try: ssh-keygen -t ed25519 -a 100 -f ~/.ssh/id_ed25519 -C "linuxteck@ubuntu-2026"

Info: Ed25519 provides faster, more secure keys than RSA. -a 100 increases KDF rounds to strengthen passphrase protection against offline brute-forcing.

Examples:
$ ssh-copy-id -i ~/.ssh/id_ed25519.pub user@server # Copy public key to server
$ ssh-keygen -y -f ~/.ssh/id_ed25519 # Print public key from private key
$ ssh-keygen -lf ~/.ssh/id_ed25519.pub # View key fingerprint and bit length

Note: RSA needs 4096 bits to match Ed25519 (256-bit) security. Ed25519 is the modern OpenSSH default. Use RSA only if connecting to legacy systems.

Follow @LinuxTeck for more #LinuxTips
Shared Hosting vs VPS vs Cloud Hosting: Which One Actually Fits Your Website?

Choosing the wrong hosting often means paying for resources you don't need—or running into performance limits sooner than expected.
I put together a practical comparison covering:
Shared Hosting vs VPS vs Cloud Hosting
Performance, pricing, and scalability
Best hosting for WordPress, WooCommerce, SaaS, and business websites
When it's actually time to upgrade
Feedback and real-world experiences are always welcome.
https://www.linuxteck.com/shared-hosting-vs-vps-vs-cloud-hosting/
#LinuxTeck
Quick Linux Tip #36

Question: My connection to a server is slow. Where in the network is the bottleneck?

Try: mtr -rw -c 20 google.com

Info: mtr combines traceroute and ping. -r enables report mode, -w shows full hostnames, and -c 20 sends 20 pings per hop.

Examples:
$ mtr google.com # Interactive real-time mode
$ mtr --tcp -P 443 google.com # TCP mode on port 443
$ mtr -j google.com # Output JSON for scripting

Note: Loss% at intermediate hops is often ICMP rate-limiting. Look for packet loss that persists through to the final hop for actual problems.

Follow @LinuxTeck for more #LinuxTips
Wayland, GNOME, KDE Plasma, COSMIC, XFCE, and LXQt are shaping the Linux desktop experience in 2026.

This guide explains the biggest desktop trends, who they're for, and how to verify them using real Linux commands.

https://www.linuxteck.com/linux-desktop-trends/

#Linux #LinuxDesktop #Wayland #GNOME #KDE #LinuxTeck
Quick Linux Tip #37

Question: My backup is killing disk performance. How do I slow it down?

Try: ionice -c 3 -p $$

Info: ionice sets I/O priority. Class 3 (idle) only allows disk access when no other process needs it.

Examples:
$ ionice -c 3 nice -n 19 rsync -av /src /dst # Throttles CPU + I/O
$ ionice -c 2 -n 7 tar -czf backup.tar.gz /data # Best-effort, low priority
$ sudo ionice -c 1 -n 4 -p 1234 # Real-time priority (root only)

Note: Classes: 1=Real-time (root only), 2=Best-effort (default), 3=Idle. Combine ionice with nice for complete system throttling.

Follow @LinuxTeck for more #LinuxTips
Archiving & Compression in Linux: tar vs gzip vs xz vs zip Explained
Description:
Master Linux file archiving and compression with this practical guide. Learn when to use tar, gzip, bzip2, xz, and zip, compare their strengths, and discover the essential commands every Linux user should know.
https://www.linuxteck.com/archiving-and-compression-in-linux/
#Linux #LinuxCommands #DevOps #SysAdmin #LinuxTips #OpenSource #LinuxTeck
Why Developers Trust Debian

Debian continues to power servers, cloud workloads, containers, and development environments because of its stability, long-term support, and predictable updates.
Read the complete guide:
https://www.linuxteck.com/why-developers-trust-debian-for-their-work/
#linuxteck #Debian #Linux #OpenSource #DevOps #SysAdmin
Learn Hyprland the Easy Way

Want to start using Hyprland but don't know where to begin?
This practical guide walks through installation, configuration, keybindings, Lua support, and screen sharing so you can build your first productive Wayland desktop with confidence.
📖 https://www.linuxteck.com/learn-hyprland-the-easy-way/
#linuxteck #Hyprland #Wayland #Linux #OpenSource #ArchLinux #Ubuntu
Quick Linux Tip #38

Question: How do I make my custom app automatically restart on crash?

Try: sudo systemctl edit --force --full myapp.service

Info: Restart=on-failure restarts the app on non-zero exits/crashes, while RestartSec adds a delay before restarting. Use StartLimitBurst in [Unit] to prevent infinite crash loops.

Examples:
$ sudo systemctl status myapp # View service status
$ sudo journalctl -u myapp -f # Follow application logs in real-time
$ sudo systemctl reset-failed myapp # Reset crash rate limits

Note: Restart modes include no, always, on-failure, and on-abnormal. always triggers even on clean exits (0), whereas on-failure is recommended for standard services.

Follow @LinuxTeck for more #LinuxTips
Master Linux Job Control

Working in the Linux terminal?
Learn how to use &, jobs, fg, bg, and Ctrl+Z to manage long-running commands without losing your workflow.
A practical guide with real-world examples for Linux users and system administrators.
https://www.linuxteck.com/job-control-fg-bg-jobs/
#linuxteck #Linux #Bash #Shell #DevOps #OpenSource
Quick Linux Tip #40

Question: Which files changed during the incident window last Tuesday?

Try: find /var/www -type f -newermt '2026-07-23 14:00:00' ! -newermt '2026-07-23 16:00:00'

Info: -newermt 'DATE' matches files modified AFTER a timestamp. Combined with ! -newermt, it isolates files modified BETWEEN two specific times—ideal for forensic analysis.

Examples:
$ find / -newermt '1 hour ago' -type f 2>/dev/null # Modified in the last hour
$ find /home -newermt yesterday ! -newermt today # Modified yesterday only
$ find /etc -newermt '2026-07-01' ! -newermt '2026-07-31' -type f # Within date range

Note: Supports natural language strings like 'yesterday', '1 hour ago', or 'last week'. You can also use -newerct (change time) or -neweramt (access time).

Follow @LinuxTeck for more #LinuxTips
Quick Linux Tip #41

Question: How do I find duplicate files even if they have different names?

Try: find /home/linuxteck -type f -exec md5sum {} + | sort | uniq -w32 -D

Info: md5sum hashes file contents, sort groups identical hashes, and uniq -w32 -D compares the 32-character hash to output all duplicate files.

Examples:
$ find . -type f -exec md5sum {} + | sort | uniq -w32 -d # Show 1 sample per duplicate set
$ fdupes -r /home/linuxteck # Dedicated tool (apt install fdupes)
$ rdfind -deleteduplicates true /home/linuxteck # Auto-delete duplicates safely

Note: For large directories, fdupes or rdfind are purpose-built and significantly faster. Use sha256sum instead of md5sum if collision risk is a concern.

Follow @LinuxTeck for more #LinuxTips
❤1
Linux DNS Troubleshooting Made Easy

DNS failure on Linux? Start with evidence instead of restarting services.
This practical workflow covers connectivity, /etc/resolv.conf, dig, NSS lookup order, systemd-resolved, NetworkManager, containers, and automated DNS health checks.
Useful for Ubuntu, Rocky Linux, and RHEL admins.
Read the full guide : https://www.linuxteck.com/linux-dns-troubleshooting-made-easy/
#LinuxTeck #Linux #DNS #DevOps #SysAdmin #LinuxAdministration
Quick Linux Tip #42

https://www.linuxteck.com/linux-tips/tee-command-linux/

Tip Question: How do I watch a long command run AND save its complete output?

Try: ./deploy.sh 2>&1 | tee -a deploy.log

Info: tee splits stdout to both terminal and file. 2>&1 redirects stderr into stdout first to capture error logs. -a appends output instead of overwriting.

Examples:
$ ./script.sh 2>&1 | tee output.log # Overwrite log with output + errors
$ make 2>&1 | tee build.log | grep -E 'error|warning' # Log all, filter display
$ sudo apt upgrade 2>&1 | tee -a /var/log/upgrades.log # Append system upgrade log

Note: Without 2>&1, tee only captures standard output and misses error messages. Use tee -a when running repeated scripts to maintain a history.

Follow @LinuxTeck for more #LinuxTips
❤1
Quick Linux Tip #43 https://www.linuxteck.com/linux-tips/linux-tips-sed-extract-text-between-markers/

Question: How do I extract config values from between BEGIN and END markers?

Try: sed -n '/BEGIN CERTIFICATE/,/END CERTIFICATE/p' /etc/ssl/certs/server.crt

Info: sed -n suppresses automatic printing. The pattern '/START/,/END/p' prints all lines between two matching delimiters (inclusive).

Examples:
$ sed -n '/^\[database\]/,/^$/p' config.ini # Extract section until empty line
$ awk '/BEGIN/,/END/' file.txt # Equivalent using awk
$ sed -n '/ERROR/,+5p' logfile # Print ERROR line plus next 5 lines

Note: Range matching /X/,/Y/ works line-by-line from first match of X to next match of Y. The +N relative line count syntax is a GNU sed extension.

Follow @LinuxTeck for more #LinuxTips click here- https://www.linuxteck.com/linux-tips/
Your DevOps Skills Aren’t Complete Without Networking
Caption:
A lot of “application problems” are actually networking problems. This guide covers a practical approach to troubleshooting DNS, routes, ports, firewalls, SSH, IPv6, and cloud networking on Linux.
Read the guide → https://www.linuxteck.com/networking-skills-for-devops/
#LinuxTeck
Quick Linux Tip #44 : https://www.linuxteck.com/linux-tips/linux-tips-check-tcp-packet-loss-ss/

Question: My connections feel unreliable. How do I check for hidden packet loss?

Try: ss -ti | grep -A3 'ESTAB' | head -20

Info: ss -ti dumps TCP internal metrics. Look for retrans:X/Y (X current retransmits, Y total) and rtt (round-trip time). Non-zero retransmits signal packet loss or network congestion.

Examples:
$ ss -ti state established '( dport = :443 )' # Inspect HTTPS connections
$ watch -n 1 'ss -s' # Monitor overall socket summary
$ netstat -s | grep -i 'retrans\|reset' # Global TCP retransmission counters

Note: When retransmissions occur, cwnd (congestion window) shrinks automatically. Persistent retransmits across multiple endpoints point to network hardware issues rather than application bugs.

Follow @LinuxTeck for more #LinuxTips click here : https://www.linuxteck.com/linux-tips/
Quick Linux Tip #45 - https://www.linuxteck.com/linux-tips/fix-windows-file-encoding-linux/

Question: My Windows files have wrong encoding on Linux. How do I fix them all?

Try: find . -name '*.txt' -exec sh -c 'iconv -f WINDOWS-1252 -t UTF-8 "$1" -o "$1.utf8" && mv "$1.utf8" "$1"' _ {} \;

Info: iconv converts text encodings (-f=from, -t=to). Wrapping in sh -c enables chaining iconv and mv per file. The _ acts as a placeholder for $0 in the subshell.

Examples:
$ iconv -f UTF-16 -t UTF-8 windows.txt -o linux.txt # Convert single file
$ iconv -l | grep -i utf # List all supported UTF encodings
$ dos2unix *.txt # Fix CRLF line endings only

Note: Always test on a backup copy first! Use iconv -l to see all supported charsets. Use dos2unix if you only need to fix line endings (CRLF to LF).

Follow @LinuxTeck for more #LinuxTips click here : https://www.linuxteck.com/linux-tips/