Paul Morrissey

Global Active “Datastore” with VSP G1000 GAD is now VMware Metro Storage Cluster certified (block and file)

Blog Post created by Paul Morrissey Employee on Aug 25, 2014

"Global Active Datastore" ready for active-active datacenters. Just received notification that we're officially vSphere Metro Storage Cluster (VMware vMSC) certified for 5.5 and 5.5U1 with both a new file certification and also new block certification taking advantage of some new high availability technology that went we just went GA. With this, Hitachi Data Systems can claim to be one of the two vendors to have vMSC certification for both block and file implementations for a more flexible software defined datacenter (SDDC) . To recap on VMware vMSC, VMware vSphere Metro Storage Cluster (VMware vMSC) is a configuration option that allows for the use of stretched clusters, meaning that ESXi nodes within a cluster are spread across metro or geographical locations. This configuration allows organizations to perform disaster avoidance, load balancing and nondisruptive live migrations between active data centers. This is a configuration that we at HDS are seeing becoming more prevalent. This ability for a stretched cluster based deployment designed for disaster avoidance in environments where downtime cannot be tolerated for those business and mission critical VM workloads is being embraced.


What is even more interesting for us is the new technology that went general availability for VMware Metro Storage Cluster, specifically VSP G1000 with Global Active Device (GAD).


In a nutshell, GAD greatly simplifies and automates high availability to ensure continuous operations for your most mission critical data and applications. It's a shared logical datastore stretched over a campus or metro distance being written too (and read) by both datacenters simultaneously ( we take care of the coherency with bi-directional mirroring) so at any point in time a VM needs to vMotion or restart on the other side, the data is already up-to-date…no movement of data loss of data…Zero RPO…  no appliances….and with no performance compromises required.. We are enabling vSphere environments to simply read datastores locally and write to both locations simultaneously, all impervious to ESXi hosts. That is software defined datacenter (SDDC) flexibility. Another quiver in our unbreakable hardware and unique 100% data availability guarantee. If you have non-HDS storage, we can virtualize that 3rd party storage with our storage virtualization technologies to bring this class of availability to your environment.

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Administration Required

Step 1. Create a Global Active Volume / Provision Datastore to your ESXi cluster on both sites.

Step 2. Done.


Common Question: Distance?: The practical distance for synchronous replication ranges from 20 miles (32 km) to 100 miles (161 km), depending on link. Synchronous replication up to 190 miles (300 km) requires using WAN-optimized controllers but generally needs to be 5ms RTT threshold.

Below are some screenshots showcasing some of the use cases and how we address those, whether block and file (NFS). These cover mobility, storage disruption or datacenter outages. Our GAD capability is available with the VSP G1000 class systems but we also support the file (NFS) implementation with VSP and HUS-VM. 



Are you considering vSphere Metro Storage Cluster configuration for your environment. Be fearless with Hitachi !.. Visit the global-active device product page on for further details