Architecting Microsoft SQL Server on VMware vSphere®

Planned downtime typically accounts for more than 80 percent of data center downtime. Hardware
maintenance, server migration, and firmware updates all require downtime for physical servers and
storage systems. To minimize the impact of this downtime, organizations are forced to delay maintenance
until inconvenient and difficult-to-schedule downtime windows.
The vSphere vMotion and vSphere Storage vMotion functionality in vSphere makes it possible for
organizations to reduce planned downtime because workloads in a VMware environment can be
dynamically moved to different physical servers or to different underlying storage without any service
interruption. Administrators can perform faster and completely transparent maintenance operations,
without being forced to schedule inconvenient maintenance windows.
vSphere 6 introduced three new vSphere vMotion capabilities:
 Cross vCenter vSphere vMotion – Allows for live migration of virtual machines between vCenter
instances without any service interruption.
 Long-distance vSphere vMotion – Allows high network round-trip latency times between the source
and destination physical servers of up to 150 millisecond RTT. This technology allows for disaster
avoidance of much greater distances and further removes the constraints of the physical world from
virtual machines.
 vMotion FCI node – Starting with vSphere 6, it is possible to use vSphere vMotion to migrate virtual
machines that are part of Microsoft failover clustering using a shared physical RDM disk.
These new vSphere vMotion capabilities further remove the limitations of the physical world allowing
customers to migrate SQL servers between physical servers, storage systems, networks, and even data
centers with no service disruption.

2.2.1.4. Site Recovery Manager
Site Recovery Manager is a business continuity and disaster recovery solution that helps you to plan,
test, and run the recovery of virtual machines between a protected site and a recovery site.
You can use Site Recovery Manager to implement different types of recovery from the protected site to
the recovery site.
 Planned migration – The orderly evacuation of virtual machines from the protected site to the
recovery site. Planned migration prevents data loss when migrating workloads in an orderly fashion.
For planned migration to succeed, both sites must be running and fully functioning.
 Disaster recovery – Like planned migration except that disaster recovery does not require that both
sites be up and running. For example, if the protected site goes offline unexpectedly. During a
disaster recovery operation, failure of operations on the protected site are reported but otherwise
ignored.
Site Recovery Manager orchestrates the recovery process with the replication mechanisms to minimize
data loss and system down time.
A recovery plan specifies the order in which virtual machines start up on the recovery site. A recovery
plan specifies network parameters, such as IP addresses, and can contain user-specified scripts that Site
Recovery Manager can run to perform custom recovery actions on virtual machines.
Site Recovery Manager lets you test recovery plans. You conduct tests by using a temporary copy of the
replicated data in a way that does not disrupt ongoing operations at either site.