Failover And Failback With Srm; Failover; Failback; Failback Scenario With Srm - HP XP20000/XP24000 Administrator's Manual

5 Failover and failback with SRM

This chapter discusses failover and failback with SRM. It also provides a scenario as a guide for the
manual failback process.

Failover

Failover occurs when an SRM recovery plan is executed, and the SRM recovery plan is configured
to fail over SRM protection groups that use replicated P-VOLs and S-VOLs on a disk array as a
datastore. During normal operation, the replication path is from a protected site (local site) to a
recovery site (remote site).
When a failure occurs at the local site (due to hardware failure or the entire site loss), a failover occurs
and the replication path is reversed from the recovery site to the protected site. With the P9000
Virtualization Adapter and SRM, the failover process is an automated feature and the process is
executed using a recovery plan located at the recovery site.

Failback

Failback is the process of setting the replication environment back to its original state at the protected
site (local site) after a failover. Failback can be managed as a normal server migration process.
Managing the failback with SRM is a manual process and the steps vary with respect to the degree
of failure at the protected site (local site). For example, the failover could have been due to a hardware
error or the loss of the entire data center.

Failback scenario with SRM

In the following failback scenario, SRM is used as a failback tool to return a protected site (Site A) to
its original state after executing a recovery plan (R1) at a recovery site (Site B).
To execute a failback manually after site A is recovered:
1. Delete recovery plan at the recovery site (Site B).
2. If the protected site (Site A) still has DR protection configured for the protection groups (P1) in
recovery plan (R1), delete protection groups (P1) at the protected site.
This could be the case if some of the hardware at the protected site was not replaced after a
disaster and you are employing the existing hardware. If new hardware has been installed, this
is not necessary.
3. If you have not done so already, install SRM and P9000 SRA on the updated hardware at the
protected site (Site A).
4. Using the VI Client at the recovery site (Site B), establish the protected site (Site A) as the secondary
site for the recovery site (Site B).
This means you create site B as protected site and site A as the recovery site just for the purpose
of failing back the Continuous Access device group and the VMs on it.
P9000 Virtualization Adapter Administrator Guide 41