Category Archives: Linux

19 April, 2026

Deploying Secondary Bind9 as a DNS Server on Ubuntu Server

Configure BIND9 secondary DNS on Ubuntu Server. Set up zone transfers, recursion ACLs, and firewall rules for a resilient secondary name server.

18 April, 2026

Deploying Bind9 as DNS Server on Ubuntu Server

Configure Bind9 on Ubuntu Server with secure ACLs and zone files. Learn to set up authoritative DNS, restrict recursion, and verify queries with dig.

24 March, 2026

Useful Linux Commands

Master basic Linux commands for navigation, file management, and permissions. Learn to use pipes, redirection, and chmod to automate tasks efficiently.

15 February, 2026

Adding XRDP to your Ubuntu Desktop

Install XRDP on Ubuntu to enable RDP access. Fix Wayland errors and configure Xorg for stable remote desktop connections with copy-paste support.

9 February, 2026

Installing OpenSource SAML in Your Lab Environment

Install Authentik using Docker Compose on Ubuntu. Configure an open source SAML server for your FortiGate lab environment with this step-by-step guide.

7 February, 2026

Understanding Netplan on Linux

Learn to configure Netplan on Linux using YAML files. Understand lexicographical file priority and predictable interface naming to manage network settings reliably.

30 December, 2025

Using Multiple SSH Keys in SecureCRT and macOS CLI

Learn to configure multiple SSH keys in SecureCRT and macOS CLI. Includes FortiGate SSH key auth setup and OpenSSH key management for network engineers.

27 December, 2025

Ubuntu UFW (Uncomplicated Firewall); The complete How To

Configure Ubuntu UFW firewall rules and app profiles. Learn to install UFW, enable SSH access, and manage inbound and outbound traffic policies on Linux.

25 July, 2024

Deploying Linux Instances in AWS

Learn how to deploy an AWS Linux instance and configure SecureCRT for SSH access. Includes correct username selection and PEM key setup for secure...

14 August, 2021

Using PhoneInfoga to research phone numbers

Learn how to use PhoneInfoga for phone number lookup via command line or web GUI. Download, install, and scan numbers to identify unknown callers.

18 May, 2020

FortiClient CLI for Linux using Realms

Configure FortiClient CLI Linux realms for SSL-VPN access. Learn the exact command line syntax and FortiGate portal mapping steps to fix connection failures.

14 May, 2020

Built-In “IPerf” on the FortiGate Firewall

Learn how to run iperf3 tests on FortiGate using diag traffictest. Configure server and client modes to validate throughput and connectivity.

11 May, 2020

Doing “IP Chicken” from the CLI

Check your public IP address from the Linux command line using dig or curl. Includes installation steps for CentOS and Debian systems.

1 April, 2020

Setting Static IP Address on an Ubuntu Server

Learn how to set a static IP address on Ubuntu Server using Netplan. Edit 50-cloud-init.yaml correctly to switch from DHCP to a fixed IP...

7 March, 2020

Using OpenSSL to encrypt files

Learn how to encrypt files with OpenSSL on macOS and Linux. Use simple command line steps to secure data at rest and decrypt it...

2 March, 2020

Bash Script to dig a list of IP Addresses

Use this bash script to dig a list of IP addresses for PTR records. Automate reverse DNS lookups and export results to CSV for...

6 February, 2020

Installing SecureCRT on Ubuntu 19.10

Install SecureCRT on Ubuntu 19.10 by manually adding missing libssl and libpython dependencies. Follow these CLI steps to resolve package errors and get your...

30 January, 2020

Live Ubuntu USB with Persistence

Learn how to create an Ubuntu Live USB with persistence using mkusb. Build a portable Python development environment for school laptops that saves files.