The Redbooks team is pleased to announce the publication of  the follwing IBM Redbooks:

Implementing VersaStack with Cisco ACI Multi-Pod and IBM HyperSwap for High Availability 

The IBM Spectrum Virtualize HyperSwap function is a high availability feature that provides active-active access to a volume at two sites up to 300 km apart. HyperSwap functions are available on Spectrum Virtualize systems that can support more than one I/O group.

HyperSwap volumes maintain a fully independent copy of the volume data at each site. When data is written by hosts at either site, both copies are synchronously updated before the write operation is completed. If one site is no longer available, the other site continues to provide access to the volume. The following figure  shows an example Storwize HyperSwap configuration with underlying Volume Mirrors for additional redundancy.

In a HyperSwap configuration, each site is an independent failure domain. If one site experiences a failure, then the other site can continue to operate without disruption. You must
also configure a third site to host a quorum device or IP quorum application that provides an automatic tie-break during a link failure between the two main sites. The main site can be in
the same room or across rooms in the data center, buildings on the same campus, or buildings in different cities. Different kinds of sites protect against different types of failures.

In this book we discuss several IBM Spectrum Virtualize HyperSwap scenarios with VersaStack. The following shows the table of contents:

- Chapter 1 - Introduction and HyperSwap solution architecture
- Chapter 2 - Testing environment overview
- Chapter 3 -  Design and planning considerations
- Chapter 4 -  Implementing the HyperSwap solution
- Chapter 5 -  SVC HyperSwap diagnostic and recovery guideline

This book is intended for pre-sales and post-sales technical support professionals and storage administrators who are tasked with deploying a VersaStack solution with IBM HyperSwap.