It goes into node setup first, so once you put in an IP for the node management interface you can choose to continue with cluster setup at the CLI, or you can connect to the node management IP in a browser and use the onbox system setup wizard.
Before going into the system setup GUI though, you may need to assign the disks from the CLI:
run local disk assign all
Then you can walk through the setup in the GUI (pick single node cluster on the first screen). At the end of the setup process you can continue on to either application provisioning or to the main system manager interface.
Alternatively you can just run cluster setup at the cli and keep doing it the way you've been doing it. Aside from getting prompted for the node management IP up front the rest is the same.
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