Virtual networks have become a crucial component of both enterprise and public infrastructures, offering flexible and efficient network traffic management and security. VyOS, an open-source network operating system based on Debian, provides a robust platform for configuring routers, firewalls, and VPNs. This article provides a detailed guide on creating and managing virtual networks using VyOS on CentOS 7.

Prerequisites

Before getting started, you'll need:

• A CentOS 7 server installed with internet connectivity.
• Superuser (root) privileges or a user with sudo permissions.
• The VyOS image downloaded from the project's official website.

Installation and Configuration of VyOS

1. Preparing the Virtual Environment

   a. Install virtualization software (e.g., KVM) on CentOS 7 using the following command:

   sudo yum install qemu-kvm libvirt virt-install bridge-utils libvirt-python
   

   b. Start and enable the libvirt service:

   sudo systemctl start libvirtd
   sudo systemctl enable libvirtd
   

2. Creating a Virtual Machine for VyOS

   a. Use the virt-install tool to create a new virtual machine for VyOS:

   sudo virt-install --name=vyos --ram=1024 --vcpus=1 --disk path=/var/lib/libvirt/images/vyos.img,size=10 --cdrom /path/to/VyOS.iso --network bridge=virbr0,model=virtio --graphics none --os-type=linux --os-variant=generic
   

   b. Log in to the VyOS virtual machine using the virsh console:

   sudo virsh console vyos
   

3. Basic Configuration of VyOS

   After successfully logging into the VyOS system:

   • Set a password for the vyos user using the command set system login user vyos authentication plaintext-password 'yourPassword'.
   • Configure network interfaces and set a static IP address or use DHCP.
   • Save the configuration using the save command.
   • Restart the system to apply the changes.

Managing Virtual Networks

1. Routing Configuration

   Virtual networks require proper routing configuration. In VyOS, you can use static routing or dynamic routing protocols such as OSPF or BGP for this purpose.

2. Firewall Setup

   Securing the virtual network is crucial. VyOS allows configuring firewall rules to control access and filter traffic.

3. VPN and Encrypted Tunnels

   For secure access between different segments of the virtual network, VPN tunnels can be utilized. VyOS supports several types of VPN, including IPsec and OpenVPN.

VyOS on CentOS 7 offers a flexible and powerful platform for creating and managing virtual networks. Whether for simple home use or complex enterprise deployment, VyOS provides the tools necessary for efficient network infrastructure management. It's important to regularly update VyOS and CentOS to ensure system security and stability.