HP OpenView Storage Mirroring User Guide (360226-002, May 2004)

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! Glossary
Glossary
Alerts—Notifications, warnings and errors that describe Storage Mirroring processes.
Auto-disconnect—When the Storage Mirroring queue has reached its maximum, the auto-disconnect process empties the
source queue and the source/target connection is broken.
Auto-reconnect—The process that automatically reestablishes any source/target connections that were active before a
Storage Mirroring failure on the source machine.
Auto-remirror—If a source or target machine fails, auto-remirror automatically initiates the mirroring process after the
target machine is back online or an auto-reconnect has occured.
Block Checksum Comparison—Formula applied to two blocks of data to determine if the binary make-up of the blocks are
identical. Also called a checksum comparison.
Cluster—A group of independent servers, called nodes, working together as a unit.
Connection—The link between a source replication set and a target machine. This is a logical connection that refers to the
relationship between the replication set on the source and the copy of the data on the target, as well as the status of the
connection.
Connection ID—A unique ID associated with each Storage Mirroring connection.
Drive Shares—Any volume, drive, or directory resource that is shared across a network. During failover, the target can
assume or add any source shares so that they remain accessible to the end users.
Failover Timeout—The amount of time before failover begins. The time is calculated by multiplying the values of the monitor
interval and missed packets settings, and is displayed in the Failover Control Center.
File Change—The creation, modification, or deletion of a file. Also called a file request or operation.
Groups—Groups exist on a cluster to provide an administrative method for collecting multiple resources together for simple
management.
LogViewer—The Storage Mirroring logging utility that logs processing notifications, warnings, and errors. The logs are viewed
with the LogViewer.
MAC Addresses—Media Access Control addresses represent the physical station or hardware address of a NIC. These
addresses are used to identify computers on a network. MAC addresses are unique and are coded into every network adapter
by the manufacturer.
Mirror—Mirroring is the process of transmitting data contained in a replication set from the source to the target machine so
that an identical copy of data exists on the target machine.
Missed Packets—The configurable setting that specifies how many monitor replies can be missed before assuming a source
machine has failed.
Monitored IP Address—Those IP addresses on a source that have been selected to be monitored for failure by a Storage
Mirroring target.
Monitor Interval—The configurable failover setting that specifies how often the monitor request is sent to a source machine.
Monitor Reply—The acknowledgement that a source sends to a target indicating that it is still online.
Monitor Request—An inquiry sent from a target to a source to determine if the source is still online.
MSCS—Microsoft Cluster Service. This is Microsoft’s clustering solution. A cluster is a group of independent servers, called
nodes, working together as a unit.
Node—An independent server that is one of the units that make up a cluster.
One-to-One Configuration—Configuration used when one target machine is dedicated to support one source machine for
mirror and replication data.
One-to-One Connection—Mirror and replication data are copied to the same volume and directory structure on a target as
they exist on a source. For example,
c:\data and d:\files on the source are copied to c:\data and d:\files,
respectively, on the target.
Queue—A first-in, first-out pool of operations on the source waiting to be transmitted to a target, or a first-in, first-out pool
of operations waiting to be written to disk on the target.
Quorum—The quorum resource is used on a cluster to guarantee that only one active node operates as the cluster, acting
as a tie-breaker in the unlikely event that cluster nodes are running but cannot communicate.
Recursion—The process of automatically applying a replication set rule to the subdirectories of the named directory.
Remirror—Repeating a mirror process to guarantee the integrity of the data on the target.