Networks

Installation GNS3 in Debian 12

In this article, I present an update of the process of installing GNS3 in Debian 12, based on the previous post for Debian 11. If you need more detailed details about the installation or configuration of GNS3, I recommend you review the previous version. GNS3 installation We update the repositories and install the available system updates. javiercruces@HPOMEN15:~$ sudo apt update -y && sudo apt upgrade -y We install the necessary dependencies for GNS3, including Python, virtualization tools (KVM, QEMU, libvirt), additional libraries (PyQt5, dynamipes) and other utilities.

Sunday, September 8, 2024 | 3 minutes Read

Installation of android in GNS3 with KVM

To download the android image you can do it from this page – > https://www.fosshub.com/Android-x86.html: wget https://www.fosshub.com/Android-x86.html?dwl=android-x86_64-9.0-r2.iso Create a KVM machine as if it were a Debian, I’ve given it 2GB of RAM and 2 Cores: In our case we can launch an automatic installation: When you have the machine installed, turn off the machine and we’ll import it in gns3. To do this we will take the KVM disk and import it into the directory where we have installed the GNS3 images, then property the copied disk to your user.

Thursday, March 28, 2024 | 1 minute Read

Basic IPv6 Scenario

Throughout this guide, we will explore the configuration of a basic scenario using IPv6 networks on both Linux and Cisco devices. We will also address the configuration of an Apache server using IPv6 capabilities. Linux IPV6 Self-Configuration Connect two Linux machines to the same switch and check that they have IPv6 connectivity using the local link address. We’ll check the IPV6 that the different pcs have. PC1 has - > fe80::ef7:42ff:fe92:0/64

Sunday, October 8, 2023 | 13 minutes Read

ARP Protocol

The Address Resolution Protocol (ARP) is fundamental in computer networks to map IP addresses to physical link layer addresses (MAC). Its main function is to find the MAC address associated with a specific IP address on a local network. When one device needs to communicate with another on the same network, it uses ARP to determine the MAC address of the destination before sending data. Do you think the ARP question is a message of dissemination? Make a Wireshark capture of an ARP request and analyze it to justify your response. Yes, it is a message of dissemination as in the header we can see that the destination has a broadcast address. This address is the one that has all its bits at 1 which in the mac addresses is translated into FF:FF:FF:FF:FF:FF.

Friday, September 8, 2023 | 7 minutes Read

GNS3 switch configuration

You will learn to configure switches in GNS3, both generic devices and Cisco switches, using the VLans concept to segment the network and explore the complexities of network management. Stage preparation The first thing I’ll do is set up the stage: Customer network configuration Then set up the network cards of the customers, taking advantage that the NAT cloud includes a DHCP server. To do this, we write on the VPCS the following command:

Friday, September 8, 2023 | 11 minutes Read

Installation GNS3 and Wireshark in Debian

**This post was developed for Debian 11. If you have a more recent version, you can review the Debian 12 post you will find in the network section of the same page. The only part you should not follow if you meet this condition is the installation of GNS3. The rest of the content is still valid. –>

Friday, September 8, 2023 | 19 minutes Read

IPv6 Tunnels

Introduction In this detailed post, we explore the process of configuring IPv6 to IPv4 tunnels and vice versa in Linux and Cisco environments. As the migration to IPv6 gains importance, the ability to establish communication between IPv4 and IPv6 networks becomes essential. We will cover the basics of tunnel configuration, including the most common types of tunnels, such as 6to4 and Teredo. Additionally, we will provide step-by-step instructions for configuration on both Linux systems and Cisco devices.

Friday, September 8, 2023 | 10 minutes Read

NAT Cisco and Linux Configuration

In this article, we will explore the configuration of SNAT (Source Network Address Translation) and DNAT (Destination Network Address Translation) in scenarios with public addresses, using routers in Linux environments and Cisco devices. Scenario with debian machines Preparation of the environment Installation of packages Once the machines are placed we must download Apache for the web servers, to do this we will connect both servers to a switch and this to the NAT cloud for Internet access.

Friday, September 8, 2023 | 14 minutes Read

Network monitoring commands

A document in which the main commands are detailed when it comes to detecting and solving network incidents. Windows Command Explains the meaning of the different parameters to be configured in the TCP / IP Properties in Windows We have to keep in mind that every configuration we make is independent for each of our network adapters. To access these parameters we will follow the following route in our system:

Friday, September 8, 2023 | 23 minutes Read

OpenStack routing

In this practice, we will explore the creation of a scenario through the OpenStack orchestration and then we will conduct the routing to ensure connectivity between the different virtual machines. This exercise will allow us to understand and apply the use of OpenStack to manage virtual environments, as well as to set up the network efficiently to facilitate communication between different devices on the stage. Scenario to ride in OpenStack In order to mount our OpenStack scenario due to the current situation of the images available, we will need to prepare an instance that has password access enabled. In addition, if you want to set up another one to enable the ssh password access for this user.

Friday, September 8, 2023 | 4 minutes Read

Underworld

Introduction You live in UNDERWORLD. In your world, there are different types of species with one goal: to “crossbreed” with each other. These creatures are: VAMPIRES WEREWOLVES (LICÁNTROPOS): Werewolves with the ability to return to their human form. WOLFMEN (HOMBRES LOBO): Werewolves who, after their first transformation, cannot return to their human form. HUMANS: Some annoying little creatures. YOU: A tech-savvy warrior with superpowers like turning around a game that hasn’t even been released yet or having the ability to become invisible when going out to party and trying to flirt with a girl by saying things like: “Do you want me to compile your kernel, babe?” The layout of UNDERWORLD is as follows:

Friday, September 8, 2023 | 7 minutes Read

Underworld evolution

The world of UNDERWORLD has evolved greatly in recent months, so you must perform network management tasks to face the new situation. On one hand, the Internet has been discovered in the Underworld, allowing each of the sub-worlds (remember: vampires, werewolves, lycanthropes, and humans) to connect to a router that, in turn, connects them to one of the two large routers that form Underworld’s Internet, called Marcus (for humans and vampires) and Alexander (for werewolves and lycanthropes). Marcus and Alexander are connected to each other.

Friday, September 8, 2023 | 16 minutes Read