A cloud instantiation of a secondary storage system is generated. An indication to virtually rebuild one or more secondary storage clusters based on a snapshot archive stored in cloud storage is received. The one or more secondary storage clusters are virtually rebuilt in the cloud instantiation of the secondary storage system, including by reconstituting a tree data structure based on the snapshot archive. A copy of at least a portion of data of the one or more rebuilt storage clusters in the cloud instantiation to restore at least the portion of data is provided to a user destination system.