2025-09-24
Introduction
After we figured out insecure FTP, it’s time to meet its secure successors.
Here’s where confusion often arises: many people think FTPS and SFTP are the same thing.
In reality, these are two completely different protocols — with different histories and principles of operation.
What is FTPS? (FTP + Security)
FTPS (FTP over SSL/TLS) is a direct evolution of classic FTP. It takes standard FTP and “wraps” its connections in the cryptographic protocol SSL/TLS (the same one that protects websites via HTTPS).
2025-09-23
Introduction
When it comes to file transfer over a network, the first thing that comes to mind is FTP (File Transfer Protocol) — one of the oldest and most fundamental internet protocols. Despite its age, it’s still in use and serves as a starting point for understanding more complex systems.
What is FTP?
FTP (File Transfer Protocol) is a protocol designed for transferring files between computers on a network. It works on the client–server model:
2025-09-21
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.
2025-09-20
Introduction
Business process automation has become a standard: whether it’s integrating CRM with messengers, data processing, or DevOps tasks. In this article, we’ll look at what automation tools exist, how they differ, and how to choose the right solution for your needs.
Zapier
Zapier is one of the oldest and most popular automation services (since 2011). Its strength is its huge ecosystem: more than 5000 integrations, including CRMs, messengers, marketing, and financial tools.
2025-09-19
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.
What is WP-CLI?
WP-CLI (WordPress Command Line Interface) is a PHP-based tool that enables direct interaction with WordPress through the terminal. It covers almost all admin tasks and sometimes goes beyond the WordPress dashboard:
2025-09-18
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
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
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
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
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).
