US Patent 10936239 Cluster contraction of a mapped redundant array of independent nodes

Contracting a mapped redundant array of independent nodes is disclosed. In a contracted topology for a mapped storage system can be determined based on an initial topology of the mapped storage system. The contracted topology can comprise fewer mapped nodes than the initial topology. Further, the contracted topology can satisfy a rule related to data protection against a failure of a real node of a storage system corresponding to the mapped storage system. In some embodiments, the contracted topology can satisfy another rule related to data protection via distribution of data protection fragments according to the second topology. Data protection via distribution of data protection fragments can result from shifting data protection fragments prior to contraction, shifting mapped nodes based on a count of data protection fragments, etc.