Self-updating mode runs Cluster-Aware Updating as a highly available clustered role that is hosted directly on the cluster it is updating, which means the Cluster-Aware Updating clustered role and the Failover Clustering Tools it depends on must be installed on the cluster ' s own member nodes, which in this scenario are Node1 and Node2, since self-updating mode has no external coordinating computer and instead runs the update orchestration from within the cluster itself. Remote-updating mode works in the opposite way architecturally: it specifically requires that the computer coordinating and triggering the update run NOT be a member of the failover cluster being updated, so in this scenario the Failover Clustering Tools must instead be installed on Server1, which is an independent member server that has network connectivity to Cluster1 but is not one of its nodes, so it can safely coordinate updates against the cluster from the outside. This architectural split, tools on the cluster ' s own nodes for self-updating mode versus tools on an external, non-member computer for remote-updating mode, reflects the fundamental difference in where the update orchestration engine actually runs between the two CAU modes as documented by Microsoft, and it is what determines the correct answer for each half of this question.