Cluster expansion workflow

Adding two nodes to an existing cluster involves verifying that the cluster is ready for expansion, preparing the cluster, installing the new nodes, and completing the expansion.

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Verifying the cluster is ready for expansion
Before you start expanding a cluster, you must verify the planned configuration, gather the required network information, and add or replace switches, if necessary.
Preparing the cluster for expansion
To prepare a cluster for expansion, you must add node-locked licenses, verify the system health, back up the cluster's configuration, and generate an AutoSupport message.
Installing the new nodes
After the cluster is prepared, you must install the controllers and configure the node-management LIFs. If the controllers are not running the same ONTAP version as the existing cluster, or are repurposed and lack hardware-level HA, you must address those issues in Maintenance mode. Finally, you can join the nodes to the cluster.
Completing the expansion
After both nodes are joined to the cluster, you must finish configuring the newly added nodes by configuring AutoSupport and completing the SP network. You then validate the expanded cluster and generate an AutoSupport message to complete the expansion. If the cluster uses SAN, you should update LUN paths.