Chapter 8. Adding Nodes to the Cluster

The addhost tool adds nodes to a Red Hat HPC cluster.

addhost listens on a network interface for nodes that are PXE booting and adds them to a specified node group.

Node groups are templates that define common characteristics such as network, partitioning, operating system and kits for all nodes in a node group.

Open a terminal window or login to the installer node as root to add nodes.

Run addhost
```
# addhost
```
Select the node group for the new nodes. Normally compute nodes are added to the compute-rhel node group:
Select the network interface to listen on for new PXE booted node
Indicate the rack number where the nodes are located
addhost waits for the nodes to boot
Boot the nodes you want to add to the cluster. Wait a few seconds between powering up nodes so that the machines are named sequentially in the order they are started.
When a node is successfully detected by addhost a line appears in the installing node status window.
Exit addhost when Red Hat HPC has detected all nodes. The Installing node status screen does not update to indicate that the node has installed.