Asymmetric active-active access of asynchronously-protected data storage

摘要

In one aspect, a method to provide asymmetric active-active access to a first storage volume using a global cache coupled to a first and second virtual storage volumes includes replicating asynchronously the first storage volume at a first site to a second storage volume at a second site, virtualizing the first storage volume with the first virtual storage volume; and virtualizing the second storage volume with the second virtual storage volume. The first storage volume has primary storage functionality.

主权项

1. A method, comprising:
providing asymmetric active-active access to a first storage volume using a global cache coupled to a first and second virtual storage volumes, the first virtual storage volume comprising a first timer and a first protection agent, comprising:
replicating asynchronously the first storage volume at a first site to a second storage volume at a second site, the first storage volume having primary storage functionality;virtualizing the first storage volume with the first virtual storage volume at the first site;virtualizing the second storage volume with the second virtual storage volume at the second site;establishing the global cache as a cache layer that manages a coherent cache between the first virtual storage volume and the second virtual storage volume, wherein the first and second virtual storage volumes are processing nodes of the global cache;enabling access of the first storage volume, through the global cache, by a first host at the first site and a second host at the second site;exposing, by the global cache, the first virtual storage volume and the second virtual storage volume as the same volume having the same identity to the first host and the second host;accounting for a lag in updating the secondary storage volume by tagging write commands with a phase value using the first protection agent;notifying the first protection agent by the global cache of changes to the phase value; andin response to write input/output (I/O) requests, sending the phase value data in metadata of write commands issued by the first protection agent.