IBM E850C, Технический обзор и введение

Страница: 112 / 160

98
IBM Power System E850C: Technical Overview and Introduction
3.3 Geographically Dispersed Resiliency for Power
Geographically Dispersed Resiliency for Power (GDR for Power) is a tool that allows for the
remote restart of failed virtual machines in a disaster recovery scenario.
Most of the disaster recovery scenarios for virtual environments are based on two different
approaches, each one with its own benefits and points of attention: Clustered Virtual
Machines and Virtual Machine Remote Restart. Figure 3-4 shows a diagram of both disaster
recovery models.
Figure 3-4 Disaster recovery models comparison for virtualized environments
Although critical applications can benefit from the clustered virtual machines model because
of the faster RTO, its implementation can be more complex for many virtual machines.
However, non-critical environments might benefit from the Virtual Machine Remote Restart
model due to the simpler implementation and maintenance of the environment. Table 3-1
compares some aspects of both models.
Table 3-1 Disaster recovery models comparison for virtualized environments
Clustered Virtual Machines Virtual Machines Remote Restart
Complexity Individual VM configuration Host configuration
Failover Time Faster (seconds to minutes) Slower (minutes)
Cost Higher due to extra software needs
and labor Lower
Maintenance Each new VM requires a new cluster After the host is configured, new
VMs are automatically covered