Replicating a volume using snapshots

摘要

In one aspect, a method to synchronize a replica volume with a production volume includes providing a first snapshot of the production volume and a first dirty list that includes differences between the first snapshot and the replica volume; sending only a portion of the differences between the first snapshot and the replica volume to the replica site associated with a section of the production volume, generating a second snapshot of the production volume, adding differences between the first snapshot and the second snapshot to a second dirty list, erasing the first snapshot of the production volume and renaming the second snapshot to the first snapshot.

主权项

1. A method to synchronize a replica volume with a production volume comprising:
providing a first snapshot of the production volume and a first dirty list comprising differences between the first snapshot and the replica volume; sending only a portion of the differences between the first snapshot and the replica volume to the replica site associated with a section of the production volume; generating a second snapshot of the production volume; adding differences between the first snapshot and the second snapshot to a second dirty list; erasing the first snapshot of the production volume; renaming the second snapshot to the first snapshot; dividing the production volume into sections, each section corresponding to a portion of the production volume, wherein a size of a section is determined by an amount of dirty data in the first set of sections; erasing the first dirty list; renaming the second dirty list to be the first dirty list if all of the sections of the replica volume have been synchronized with the production volume; determining whether an amount of dirty locations in the second dirty list is smaller than a predetermined size; and performing a snapshot shipping mode if the amount of dirty locations in the second dirty list is smaller than a predetermined size.