2025-10-03
TCP Connection Proxying with HAProxy: A Beginner’s Guide
Introduction
If you are a beginner system administrator or developer, you’ve probably faced the task of managing network traffic.
One of the most powerful tools for this is HAProxy, a high-performance load balancer for TCP and HTTP.
In this article, we will cover:
- what TCP proxying is,
- why to use HAProxy,
- a sample configuration for beginners,
- security and monitoring tips.
What is TCP Proxying?
TCP Proxying is the forwarding of TCP connections from a client to a server (or group of servers) through an intermediary.
Unlike an HTTP proxy that operates at the application layer, TCP proxying happens at the transport layer, making it universal for any TCP protocol: from databases to mail services.
2025-10-01
Case: Launching and Registering an MTProto Proxy in 5 Minutes Using Docker
Problem
In some regions, access to Telegram may be unstable or completely blocked.
Using public proxies or VPNs is not always convenient: they can be slow, overloaded, or also blocked.
Task
🚀 Create your own fast and reliable proxy, register it in Telegram to track statistics, and optionally make it public.
Solution Choice: Docker + Official MTProto Image
Why Docker?
Docker allows you to run the proxy in an isolated container without installing unnecessary dependencies on the server. It’s clean, secure, and incredibly fast.
The docker-compose.yml file describes the entire configuration in one place, making the launch and management process trivial.
2025-09-22
Checklist: Bought a VPS — What’s Next?
Getting a new VPS is just the beginning. By default, the server is insecure and not ready for production use. This checklist will help you step by step to prepare your VPS: close security holes, enable updates, and configure the basic infrastructure.
1. First login and changing the root password
Connect to the server via SSH:
Change the temporary password to your own unique and complex one:
2025-09-21
MikroTik + Keenetic: FAQ and Step-by-Step Diagnostics
This article is compiled as a “cheat sheet” for SOHO/SMB networks: common issues, their symptoms, causes, quick fixes, and diagnostic checklists. Suitable for both engineers and admins who maintain the MikroTik ↔ Keenetic bundle.
📑 Navigation
1) EoIP “freezes” when transferring large files
Symptoms: SMB/FTP hangs, speed fluctuates, RDP drops.
Causes: incorrect MTU/MSS, fast-path with IPsec, NAT/Firewall errors.
2025-09-19
WP-CLI: A Comprehensive Guide to Managing WordPress from the Command Line
Introduction
WP-CLI is the official command-line tool for WordPress, allowing you to manage your sites without logging into the admin panel. With WP-CLI, you can install plugins, update WordPress core, manage users, handle database tasks, and even run advanced automation workflows.
In this guide, we’ll explore what WP-CLI is, how to install it, and provide practical examples of its most useful commands.
2025-09-18
Netplan: advanced network configuration (tunnels, VLAN, bridges, bonding)
Introduction
Netplan is a utility for declarative network configuration in Linux (Ubuntu, Debian, and derivatives).
It is usually used for simple cases like Ethernet or Wi-Fi, but it can do much more:
- tunnel interfaces (IPIP, GRE, VXLAN, WireGuard),
- VLAN,
- bridges,
- bonding (interface aggregation).
These features allow building complex network topologies — from home VPNs to data centers and cloud environments.
Tunnel interfaces
Tunnels encapsulate packets of one protocol into another. They are used for VPNs, inter-server connections, or network isolation.
2025-09-17
Network Troubleshooting for Beginners: Listening to the Wires
Introduction
Imagine: ping works, DNS responds, ports are open, mtr shows no loss, but curl returns errors like connection reset by peer or SSL handshake failed. There’s clearly a problem, but standard tools are powerless.
At such moments, the only option is to look at the actual traffic — in other words, “listen to the wires.” This process is called packet sniffing or packet analysis. In this article, we’ll go through how to use three key tools: tcpdump, sngrep, and Wireshark.
2025-09-16
Network Troubleshooting for Beginners: The Swiss Army Knives of Diagnostics
Introduction
Up to this point, we’ve used simple utilities for specific tasks:
ping checked connectivity,traceroute showed the path,ipconfig and arp helped with the local network,telnet and nc tested ports.
That’s like having a separate hammer, screwdriver, and wrench. But sometimes you need a multi-purpose tool. Today we’ll look at three such “all-in-one” tools:
mtr — ping + traceroute on steroids,nmap — universal network scanner,curl — a command-line browser.
mtr — Real-Time Traceroute 🚀
What does it do?
Combines the features of ping and traceroute. In real time, it shows latency and packet loss percentage for each hop along the path.
2025-09-15
Network Troubleshooting for Beginners: Is the Door Open? (Ports)
Introduction
A server’s IP address is like the postal address of an apartment building. But to reach the right apartment, you need the door number. In networking, these doors are ports.
- HTTP runs on port 80.
- HTTPS — on port 443.
- Mail, databases, and other services listen on their own ports.
If a port is closed or nothing is listening on it, the site won’t open — even if the server is “alive.”
2025-09-14
Network Troubleshooting for Beginners: The Internet’s Phone Book (DNS)
Introduction
You’ve gone through all the checks from the previous articles:
- The computer has the correct IP address (
ipconfig). - The router responds (
ping 192.168.1.1). - Ping to a public address (
ping 8.8.8.8) works.
Looks like the internet is fine! But the browser won’t open google.com. 🤔
Welcome to the most common cause of such issues — DNS failures.
What is DNS? 📖
The internet runs on IP addresses (e.g., 142.250.184.110), but people prefer names (google.com).
