Each node in a GPU cluster can have multiple network interfaces attached simultaneously:
Interface type
Purpose
Public network
Direct internet connectivity. Nodes are accessible from the internet via their public IP.
Private network
Internal connectivity between cluster nodes and other Cloud resources in the same region. No direct internet access by default — attach a router for outbound connectivity or assign a floating IP to expose a specific node.
VAST network
A dedicated third network, available after a VAST file share is created. Required for mounting VAST NFS file shares.
Private networks use VxLAN on Virtual GPU clusters and VLAN on Bare Metal GPU clusters.
A private network with a subnet isolates cluster nodes and provides a fixed IP address range. Without a router attached to the subnet, nodes cannot initiate outbound connections — attach one when nodes need to reach package repositories, object storage, or external APIs.For inbound SSH access, assign a floating IP to the head node and use a security group to allow SSH only from trusted IP addresses.
A public network interface assigns each node a direct public IP, so no router or floating IP is needed. Use this when all nodes must pull external resources independently — container images, datasets, or model weights on each node separately.
After creating a VAST file share, a dedicated network interface becomes available in the node’s network settings. Attach it to each node that needs to mount the share — this interface does not appear until the file share exists.
Multi-node GPU communication uses InfiniBand on supported configurations and is set up automatically when the cluster is created. This interconnect is separate from the Cloud networking described above — it does not appear in network settings and requires no manual configuration.