Map-Reduce Ready Distributed File System

A computer implemented map-reduce method comprising:

• maintaining information about where each of a plurality of containers is located in a container location database (CLDB), wherein a storage pool contains zero or more containers, wherein a cluster node in a plurality of cluster nodes contains one or more storage pools;
• structuring data within said containers using a plurality of inodes;
• replicating said containers to other cluster nodes with one container designated as master for each replication chain;
• storing data in said CLDB as inodes in well known containers;
• maintaining a database in CLDB inodes, wherein said database contains at least the following information about all of said containers:
• nodes that have replicas of a container,
• an ordering of a replication chain for each container,
• wherein updates to a container are sent to a master for said updated container, and wherein changes to content of a container are propagated to said replicas of said container by said master;
• storing in said CLDB a location of all replicas of a container, a structure of a replication for said container, and an epoch number for each container, wherein said epoch number is incremented each time said replication structure for a container is changed, and wherein an epoch's changes are noted in a transaction history for each version of said container and gaps are inserted whenever said master is noted in a replication chain;
• and
• tracing back through transactions that have been applied to each copy when examining said master and target copies of a same container to determine a point in a history of two containers when they were identical.