A plurality of storage nodes, the plurality of storage nodes configured to communicate together as a storage cluster; each of the plurality of storage nodes having nonvolatile solid-state memory for user data storage; the plurality of storage nodes configured to distribute the user data and metadata throughout the plurality of storage nodes; the plurality of storage nodes configured to apply differing data striping schemes in successive data accesses; each storage node of the plurality of storage nodes having a controller; at least one storage node of the plurality of storage nodes having multiple authorities, wherein each authority of the multiple authorities controls a corresponding range of data identifiers such that the authorities are configured to control said distribution of the user data and metadata throughout the plurality of storage nodes; each authority of the plurality of storage nodes configurable to select one of a plurality of redundancy schemes independent of each other authority of the plurality of storage nodes and to distribute the user data in accordance with the selected redundancy scheme; and characterised in that: the plurality of storage nodes configurable such that changing membership of the plurality of storage nodes by adding or removing a storage node triggers the plurality of storage nodes and the authorities to reconfigure redundancy of the user data in the plurality of storage nodes by reconfiguring the data stripping scheme through self-configuration of the storage nodes; the storage nodes and the authorities are configurable to reconfigure the redundancy to provide a storage overhead decrease, as a relative amount of a total storage capacity of the storage cluster, for increasing numbers of storage nodes, as a result of reconfiguring the data striping scheme; and the user data and metadata are distributed using erasure coding that is used for recovering the data and the erasure coding scheme is in accordance with a first data striping scheme and wherein the reconfigured redundancy of the user data and metadata the erasure coding scheme is in accordance with a second data striping scheme. the plurality of storage nodes configured to communicate together as a storage cluster; each of the plurality of storage nodes having nonvolatile solid-state memory for user data storage; the plurality of storage nodes configured to distribute the user data and metadata throughout the plurality of storage nodes; the plurality of storage nodes configured to apply differing data striping schemes in successive data accesses; each storage node of the plurality of storage nodes having a controller; at least one storage node of the plurality of storage nodes having multiple authorities, wherein each authority of the multiple authorities controls a corresponding range of data identifiers such that the authorities are configured to control said distribution of the user data and metadata throughout the plurality of storage nodes; each authority of the plurality of storage nodes configurable to select one of a plurality of redundancy schemes independent of each other authority of the plurality of storage nodes and to distribute the user data in accordance with the selected redundancy scheme; and characterised in that: the plurality of storage nodes configurable such that changing membership of the plurality of storage nodes by adding or removing a storage node triggers the plurality of storage nodes and the authorities to reconfigure redundancy of the user data in the plurality of storage nodes by reconfiguring the data stripping scheme through self-configuration of the storage nodes; the storage nodes and the authorities are configurable to reconfigure the redundancy to provide a storage overhead decrease, as a relative amount of a total storage capacity of the storage cluster, for increasing numbers of storage nodes, as a result of reconfiguring the data striping scheme; and the user data and metadata are distributed using erasure coding that is used for recovering the data and the erasure coding scheme is in accordance with a first data striping scheme and wherein the reconfigured redundancy of the user data and metadata the erasure coding scheme is in accordance with a second data striping scheme. the plurality of storage nodes configurable such that changing membership of the plurality of storage nodes by adding or removing a storage node triggers the plurality of storage nodes and the authorities to reconfigure redundancy of the user data in the plurality of storage nodes by reconfiguring the data stripping scheme through self-configuration of the storage nodes; the storage nodes and the authorities are configurable to reconfigure the redundancy to provide a storage overhead decrease, as a relative amount of a total storage capacity of the storage cluster, for increasing numbers of storage nodes, as a result of reconfiguring the data striping scheme; and the user data and metadata are distributed using erasure coding that is used for recovering the data and the erasure coding scheme is in accordance with a first data striping scheme and wherein the reconfigured redundancy of the user data and metadata the erasure coding scheme is in accordance with a second data striping scheme.