VCF 9.0 states for the Simple Automation model: “Single node… Applies to Small… Can be scaled out to the high availability model by resizing the node to Medium or Large, which also forces the scale out to 3 nodes .” In addition, the Day-N procedure confirms the action is a Scale (scale-out) operation: “ Scale VCF Automation… choose a larger target deployment type such as Medium or Large… ” and provide “ Additional VIPs ” and a “ Cluster Node IP Pool ” (Medium requires a minimum of four IPs ), then submit the scale out request . Therefore, moving from Small (Simple) to Medium necessarily transitions to the High Availability (3-node) model rather than remaining a single medium node. This aligns the form factor with the documented model behavior and the fleet management workflow.

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