Stop Replicating Data, Start Protecting Applications
By Zerto, on 17 November, 2011
Disaster Recovery solutions need to provide seamless support for the mobility of VMs in a virtualized environment – but most simply don’t.
This week, an article by Michael Otey in Windows IT Pro made a strong case for virtualizing SQL – something many are “scared” to virtualize – citing reduced cost, improved resource availability and developments in DR from dynamic IT infrastructure products like Microsoft’s Live Migration or VMWare’s High Availability and vMotion.
He points out that,
“VMWare provides its High Availability clustering feature, which can automatically move protected resources to a backup server in the event of a server failure. That covers the single point of failure exposure… Virtualization lets you abstract the server workload from the underlying hardware that it runs on. This provides huge improvements for availability and disaster recovery. In the event of a disaster, restoring a VM backup is much faster than getting a bare metal restore off the ground, and it can also be faster than having a warm backup.”
Theoretically, that’s all wonderful. Restoring a backup VM is fast and there are tools that help avoid single points of failure. However, the motion of individual application components like VMs and VMDKs can break replication policy and consistency.
We call this, “application awareness”, protection that includes consistent replication and recovery of groups of VMs and all dependencies of those VMs deployed on multiple hosts and storage devices. DR solutions need to stop backing up and replicating the individual components, leaving it for the IT department to assemble the pieces at the replication site into a working application. DR solution vendors need to start replicating and recovering entire applications.
Virtual Application Awareness
With Zerto, replication and recovery is done in Virtual Protection Groups (VPGs) that represent an entire application. A VPG is configured and managed as a single entity representing an entire federated application with all its components and dependencies. The application manager can determine and control replication policy for a complete application. Physical location of the data is irrelevant.
How does a Virtual Protection Group work?
VPGs maintain replication policy and consistency for all the VMs in the protection group and completely support VM vMotion, storage vMotion and DRS. In addition to creating VPGs through Zerto’s management console, VPGs can be also created from a VMWare vApp object, replicating it with full compatibility (all vApp properties are replicated and recovered) and automatically adjusting to the addition and removal of VMs. A VPG is recovered as a whole on the recovery site while maintaining boot order with all dependencies, and we even support network re-configuration at the VPG level or specific VM level if necessary.
More information on Virtual Protection Groups can be found in our Hypervisor-Based Replication whitepaper.