Building Disaster Recovery Serviceguard Solutions Using Metrocluster with Continuous Access for P9000 and XP A.11.00

N
network failover The ability to restore a network connection after a failure in network hardware when there are
redundant network links to the same IP subnet.
notification A message that is sent following a cluster or package event.
O
off-line data
replication.
Data replication by storing data off-line, usually a backup tape or disk stored in a safe location;
this method is best for applications that can accept a 24-hour recovery time.
on-line data
replication
Data replication by copying to another location that is immediately accessible. On-line data
replication is usually done by transmitting data over a link in real time or with a slight delay to
a remote site; this method is best for applications requiring quick recovery (within a few hours
or minutes).
P
package alert Time at which a message is sent indicating a problem with a package.
package event A package condition such as a failure that causes a notification message to be sent. Package
events can be accompanied by alerts, but not alarms. Messages are for information only; the
cmrecovercl command is not enabled for a package event.
package recovery
group
A set of one or more packages with a mapping between their instances on the cluster and their
instances on the Recovery Cluster.
physical data
replication
An on-line data replication method that duplicates I/O writes to another disk on a physical block
basis. Physical replication can be hardware-based where data is replicated between disks over
a dedicated link (For Example EMC’s Symmetrix Remote Data Facility or the HP Storage E Disk
Array XP Series Continuous Access), or software-based where data is replicated on multiple disks
using dedicated software on the primary node (For Example, MirrorDisk/UX).
PV links A method of LVM configuration that allows you to provide redundant disk interfaces and buses
to disk arrays, thereby protecting against single points of failure in disk cards and cables.
PVOL A primary volume configured in an P9000 or XP series disk array that uses Continuous Access.
PVOLs are the primary copies in physical data replication with Continuos Access on the P9000
or XP.
Q, R
Recovery Cluster A cluster on which recovery of a package takes place following a failure on the cluster.
recovery package The package that takes over on the Recovery Cluster in the event of a failure on the cluster.
remote failover Failover to a node at another data center or remote location.
resynchronization The process of making the data between two sites consistent and current once systems are restored
following a failure. Also called data resynchronization.
rolling disaster A second disaster that occurs before recovering from a earlier disaster, For Example, while data
is being synchronized between two data centers after a disaster, one of the data centers fails,
interrupting the data synchronization process. Rolling disasters might result in data corruption
that requires a reload from tape backups.
S
special device file The device file name that the HP-UX operating system gives to a single connection to a node, in
the format /dev/devtype/filename.
sub-clusters Sub-clusters are clusterwares that run above the Serviceguard cluster and comprise only the nodes
in a Metrocluster site. Sub-clusters have access only to the storage arrays within a site.
SVOL A secondary volume configured in an P9000 or XP series disk array that uses Continuous Access.
SVOLs are the secondary copies in physical data replication with Continuos Access on the P9000
or XP.
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