Русский flag Русский

All Posts

pfSense: a legend proven over decades

2025-11-03

pfSense — a tank in the world of firewalls.
Is updated less often, but runs for years without surprises.


🏢 Who pfSense is for

  • Corporation with 100+ users
  • Needs official support
  • Has old but reliable hardware
  • Value stability

📚 pfSense Features

  • Multi-WAN and automatic failover
  • Traffic Shaping — bandwidth management
  • Captive Portal — guest authentication
  • OpenVPN and IPsec — encrypted tunnels

⚙️ Installation

  1. ISO → USB
  2. Install → configure WAN/LAN
  3. In about 10 minutes — a ready firewall

Example HAProxy config:

OPNsense: the firewall of the future that newbies install

2025-11-02

OPNsense — it’s like pfSense, but prettier, faster, and with an API.
Want an office firewall you wouldn’t be embarrassed to show your boss? Here it is.


💼 Who OPNsense is for

  • Office of 10–50 people
  • VPN for all employees
  • Backup internet connection
  • Modern web interface

🎨 Apple-like interface

  • Dark theme
  • Real-time graphs
  • REST API for automation
  • WireGuard out of the box

⚙️ Installation in 5 minutes

  1. Download the ISO from opnsense.org
  2. Write it to a USB stick (dd or Rufus)
  3. Boot → assign interfaces → done!

Auto-update via API:

OpenWRT: turning an old router into a powerhouse

2025-11-01

Imagine: an old router for 2000 ₽ blocks ads, shares a VPN, works as a Mesh system and doesn’t slow down even with 50 devices.
This is not magic — this is OpenWRT.


🏠 Who needs OpenWRT

OpenWRT turns an ordinary router into a mini-server. If you have at least one item from the list — it’s definitely time to try it:

  • Want AdBlock for the whole house
  • Need a VPN without a subscription
  • Have an old router lying around
  • Like to tinker with settings

90% of users install OpenWRT — and forget about the router forever.

Routing traffic from a local subnet through a remote server (IPIP + Policy Routing)

2025-10-29

This guide will show how to configure two Linux servers so that all the Internet traffic from a specific local subnet (for example, 10.100.10.0/24) is routed not via its default gateway but through an IPIP tunnel to a remote server, which will then put that traffic onto the Internet.

This is useful if you need services in one subnet to go out to the world with the IP address of another server — for example, to bypass restrictions, centralize NAT, or hide the source.

🛠️ EoIP not connecting: Tunnel troubleshooting checklist (MikroTik)

2025-10-16

The EoIP (Ethernet over IP) protocol from MikroTik is used to create an L2 tunnel over an IP network, allowing you to combine two remote local networks into a single broadcast domain.
If your EoIP tunnel does not establish (no “R” — Running flag), follow this step-by-step checklist.


1. Check IP connectivity (L3)

Before starting, make sure the routers see each other at the IP level.

Ping the remote side:

MikroTik + Keenetic: FAQ and Step-by-Step Diagnostics

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.

OpenVPN: setting up Ubuntu server and Keenetic client

2025-09-11

In this guide, we’ll go through setting up an OpenVPN server on Ubuntu and connecting a Keenetic router to it. This setup is useful if you need to provide access to your home network or forward services (e.g., PBX or web server) through VPN.


1. Preparing the Ubuntu server

1.1 Installing packages

sudo apt update
sudo apt install -y openvpn easy-rsa iptables-persistent

1.2 Creating PKI (Easy-RSA v3)

make-cadir ~/easy-rsa
cd ~/easy-rsa
./easyrsa init-pki
./easyrsa build-ca nopass

Server keys

./easyrsa gen-req server nopass
./easyrsa sign-req server server
./easyrsa gen-dh

Client keys (for Keenetic)

./easyrsa gen-req keenetic nopass
./easyrsa sign-req client keenetic

TLS key (specifically tls-auth, not tls-crypt)

openvpn --genkey secret ta.key

1.3 Distribute keys

  • In /etc/openvpn/server/:

094 | OpenVPN + Keycloak: Modern Authentication

2025-08-27

The Problem with Certificates at Scale

In previous articles, we discussed that OpenVPN uses certificates for authentication. This method is reliable but has significant drawbacks:

  • Inconvenience for users: Each user must manually receive and install their own certificate.
  • Complex management: When an employee leaves, their certificate must be revoked, which requires extra steps.
  • Lack of centralization: Each service that requires access has its own authorization system.

The solution to this problem is using a centralized identity provider such as Keycloak.

093 | OpenVPN Setup: Explaining the Basics

2025-08-26

VPN: Not Just an “On” Button

For many users, a VPN is simply an “On” button. However, when it comes to building your own secure tunnel, it’s important to understand its architecture. OpenVPN is based on two key ideas: the client-server model and Public Key Infrastructure (PKI).

The Client-Server Model

The concept is simple:

  • Server — the entry point into your secure network. It constantly “listens” for incoming requests and is ready to accept connections.
  • Client — your device (laptop, phone) that initiates the connection to the server.

Once the server and client “agree,” a secure tunnel is created between them, and all traffic passes through it.

092 | OpenVPN: One Protocol – Different Clients

2025-08-25

OpenVPN: A Time-Tested Standard

Introduction

In a world where the speed and simplicity of WireGuard have become the new standard, OpenVPN remains one of the most reliable and flexible VPN protocols. It works both on traditional computers and on networking equipment, providing cross-platform compatibility and a high level of security. However, to understand how to use it, it is important to distinguish between the protocol itself and its client applications.