Patent ID: 9727262
Date: 2017-08-08
CPC Classifications: G06F

Claim:
1. A method comprising: receiving, by a storage server, a request to make pseudo common snapshots of a first consistency group, hosted by a first storage controller, and a second consistency group hosted by a second storage controller, the first consistency group and the second consistency group having a synchronous replication relationship; enabling logging, of incoming client write requests, to an intercept tracking log at a first point in time, the intercept tracking log comprising indicators set to indicate whether portions of the first consistency group have been modified or not modified with respect to the second consistency group; performing a first drain without hold operation to drain inflight client write requests occurring before the first point in time; triggering a capture of a first pseudo common snapshot of the second consistency group at the second storage controller without pausing incoming client write requests; performing a second drain without hold operation to drain inflight client write requests occurring before the creation of the first pseudo common snapshot; and creating a second pseudo common snapshot of the first consistency group at the first storage controller without pausing incoming client write requests, the second pseudo common snapshot capturing the intercept tracking log at a state that is indicative of a delta between the first pseudo common snapshot and the second pseudo common snapshot, the delta corresponding to data differences between the first consistency group and the second consistency group as reflected between the first pseudo common snapshot and the second pseudo common snapshot.