Designing Disaster Recovery Clusters using Metroclusters and Continentalclusters, Reprinted October 2011 (5900-1881)

NOTE:
• During an alert, the cmrecovercl will not start the recovery packages unless the -f option
is used.
• During an alarm, the cmrecovercl will start the recovery packages without the -f option.
• When there is neither an alert nor an alarm condition, cmrecovercl command cannot start
the recovery packages on the target disk site. This condition applies not only when no alert
or alarm was issued, but also applies to the situation where there was an alert or alarm, but
the source disk site recovered and its current status is Up.
Failback Scenarios
The goal of HP Continentalclusters is to maximize system and application availability. However,
even systems configured with Continentalclusters can experience hardware failures at the primary
site or the recovery site, as well as hardware or networking failures connecting the two sites. The
following discussion addresses some of those failures and suggests recovery approaches applicable
to environments using data replication provided by HP 3PAR Remote Copy.
Scenario 1
The primary site has lost power, including backup power (UPS), to both the host and the storage
systems that make up the Serviceguard Cluster at the primary site. There is no loss of data on either
the 3PAR storage system or the operating systems of the systems at the primary site. After reception
of the Continentalclusters alerts and alarm, the administrators at the recovery site follow the
prescribed processes and recovery procedures to start the protected applications on the target disk
site.
After power is restored to the primary site, the Remote volume group may have the role of
"Primary-Rev" on the recovery site and the role of "Primary" on the primary site. The procedure to
Completing and Running a Continentalclusters Solution with 3PAR Remote Copy 329