Permissions required to back up, archive, restore or retrieve files on cluster resources

To back up, restore, archive, or retrieve data residing on Microsoft Cluster Server (MSCS) or Veritas Cluster Server cluster resources, your Windows account must belong to the Administrators or Domain Administrators group or Backup Operators group.

By default, Backup Operators do not have the user rights necessary to perform these tasks on a cluster node. However, Backup Operators can perform this procedure if that group is added to the security descriptor for the Cluster service. You can do that using Cluster Administrator or cluster.exe.