Setting up networks, subnets, and routers

Setting up networks, subnets, and routers in Red Hat OpenStack Platform (RHOSP)

Overview

In Red Hat OpenStack Platform (RHOSP), Neutron is the core component responsible for managing networking services. It enables the creation of various network types, including Flat, VLAN, VXLAN, GRE, and more. This content focuses on setting up networks, subnets, and routers using Neutron in RHOSP.

Networks

A network in Neutron is a logical construct representing a broadcast domain. It can be thought of as a software-defined network (SDN). In RHOSP, you can create different types of networks based on your requirements. Here we will focus on creating a Flat network, which is the simplest type of network.

Creating a Network

  1. Log in to the OpenStack Dashboard (horizon) as an administrator or a user with network-related permissions.

  2. Navigate to Project > Network > Networks.

  3. Click Create Network.

  4. Provide a name, such as my_flat_network, and select Flat as the network type.

  5. Optionally, you can also specify a description, external connectivity (if required), and other settings.

  6. Click Create to create the Flat network.

Subnets

A subnet is a range of IP addresses assigned to a specific network. To ensure proper communication within your virtual machines (VMs), you need to allocate subnets to networks.

Creating a Subnet

  1. After creating a network (e.g., my_flat_network), navigate to Project > Network > Subnets.

  2. Click Create Subnet.

  3. Provide a name, such as my_subnet, and specify the network as my_flat_network.

  4. Define the IP range for your subnet (e.g., 192.168.1.0/24).

  5. Optionally, you can also set gateway and DNS information if required.

  6. Click Create to create the subnet associated with the network.

Routers

A router in Neutron is responsible for routing traffic between different networks or subnets. This allows communication between VMs in separate networks.

Creating a Router

  1. Navigate to Project > Network > Routers.

  2. Click Create Router.

  3. Provide a name, such as my_router.

  4. Select the external network that connects your environment to the outside world (usually provided by your cloud provider).

  5. Optionally, you can also specify additional router settings, like admin state and ha (high availability).

  6. Click Create to create the router.

Adding Interfaces to Routers

To enable communication between networks or subnets, you need to add interfaces to routers:

  1. Select the newly created my_router.

  2. Navigate to the Interfaces tab.

  3. Click Add Interface.

  4. Choose the desired network (e.g., my_flat_network) and select an available subnet interface.

  5. Click Add to add the interface to the router.

Load Balancing with HAProxy

To distribute incoming traffic across multiple virtual machines for high availability and performance, you can use a load balancer like HAProxy. While this typically requires additional configuration outside of Neutron, you can set up a load balancer instance in RHOSP using Heat templates or other orchestration tools.

  1. Create an HAProxy instance (using Heat templates or other methods).

  2. Configure the load balancer with your virtual machine instances and their respective ports.

  3. Associate the load balancer with the appropriate security groups to allow incoming traffic on desired ports.

This section provided a basic outline for setting up networks, subnets, and routers in Red Hat OpenStack Platform (RHOSP). Remember that further configuration might be necessary depending on your specific use case and infrastructure requirements. Always refer to official Red Hat documentation for detailed instructions and best practices.