A method for proactively rebuilding user data in a plurality of storage nodes of a storage cluster in a single chassis is provided. The method includes distributing user data and metadata throughout the plurality of storage nodes such that the plurality of storage nodes can read the user data, using erasure coding, despite loss of two of the plurality of storage nodes. The method includes determining to rebuild the user data for one of the plurality of storage nodes in the absences of an error condition. The method includes rebuilding the user data for the one of the plurality of storage nodes. A plurality of storage nodes within a single chassis that can proactively rebuild the user data stored within the storage nodes is also provided.