Building Disaster Recovery Serviceguard Solutions Using Metrocluster with Continuous Access XP P9000 for Linux B.12.00.00

E, F
ESCON Enterprise Storage Connect. A type of fiber-optic channel used for inter-frame communication
between EMC Symmetrix frames using EMC SRDF or between HP Storage E series disk array
units using Continuous Access .
failover The transfer of control of an application or service from one node to another node after a failure.
Failover can be manual, requiring human intervention, or automated, requiring little or no human
intervention.
G - I
high availability A combination of technology, processes, and support partnerships that provide greater application
or system availability.
J, K, L
local cluster A cluster located in a single data center. This type of cluster is not disaster tolerant.
local failover Failover on the same node; this most often applied to hardware failover, For Example local LAN
failover is switching to the secondary LAN card on the same node after the primary LAN card
has failed.
logical data
replication
A type of on-line data replication that replicates logical transactions that change either the
filesystem or the database. Complex transactions might result in the modification of many diverse
physical blocks on the disk.
M
Metrocluster A Hewlett-Packard product that allows a customer to configure an Serviceguard cluster as a
disaster tolerant metropolitan cluster.
mirrored data Data that is copied using mirroring.
mirroring Disk mirroring hardware or software, such as MirrorDisk/UX. Some mirroring methods might
allow splitting and merging.
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
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 Series Continuous Access), or software-based where data is replicated on multiple disks
using dedicated software on the primary node..
PVOL A primary volume configured in an P9000 series disk array that uses Continuous Access. PVOLs
are the primary copies in physical data replication with Continuos Access on the P9000.
72 Glossary