Skip to main content

Networking Overview

Before you can deploy virtual machines, you need to set up networking. Networking in a Gallium Cluster connects your VMs to your physical network through two building blocks: adapter groups and networks.

Because a cluster spans multiple hypervisors, an adapter group exists across every hypervisor in the cluster. The networks you build on top of it are then available to virtual machines wherever they run.

How Networking Fits Together​

Networking is organized as a chain from your servers' physical hardware through to your virtual machines:

Physical Adapters  →  Adapter Groups  →  Networks  →  Virtual Machines

Physical adapters are the network interface cards (NICs) in each hypervisor. You assign them to adapter groups to make them available for VM networking.

Adapter groups are logical groupings of physical adapters that span the whole cluster. For each group you assign one or two physical adapters on every hypervisor. When two adapters are assigned on a hypervisor, they operate in an active/failover configuration — if the active adapter fails, traffic automatically switches to the other. Each adapter group can host multiple networks.

Networks are what your virtual machines connect to. Each network belongs to one adapter group and is either tagged with a specific VLAN ID or untagged. Because the adapter group spans the cluster, the network is available to VMs on any hypervisor. When you create a VM and add a network adapter to it, you select which network it connects to.

Adapter Groups​

An adapter group bundles physical NICs across the cluster to provide the underlying connectivity that networks use. You assign adapters to the group on each hypervisor; if two adapters are assigned on a hypervisor, one is active and the other is a standby failover.

You must assign adapters on every hypervisor in the cluster for each group, and you must create at least one adapter group before you can create any networks.

info

The cluster also has a dedicated infrastructure adapter group that carries cluster communication and storage replication traffic between servers. It is configured during installation and is not managed in this section, which covers the adapter groups you create for virtual machine networking. See Networking in the Planning section for details.

Networks​

A network is what you connect a virtual machine to. There are two types:

VLAN — A tagged network using the 802.1q standard. Each VLAN network has an ID between 2 and 4094 that corresponds to a VLAN on your physical network switches. Use this when your switch ports are configured as trunks carrying tagged traffic.

Untagged — A network that uses the native (untagged) VLAN on the physical switch port. Only one untagged network is allowed per adapter group.

info

If your physical network does not use VLANs, choose Untagged when creating a network.

Quick Start​

To get a virtual machine connected to the network:

  1. Create an adapter group and assign physical adapters on every hypervisor. See Adapter Groups.
  2. Create a network on that adapter group. See Networks.
  3. When creating a VM, attach its network adapter to the network.