MSA 2040 SMU Reference Guide

184 Glossary
remote replication Asynchronous (batch) replication of block-level data from a volume in a primary system to a
volume in one or more secondary systems by creating a replication snapshot of the primary
volume and copying the snapshot data to the secondary systems via Fibre Channel or iSCSI
links. The capability to perform remote replication is a licensed feature (Remote Snap).
remote syslog support See syslog.
replication image A conceptual term for replication snapshots that have the same image ID in primary and
secondary systems. These synchronized snapshots contain identical data and can be used
for disaster recovery.
replication set Associated primary and secondary volumes that are enabled for replication and that
typically reside in two physically or geographically separate storage systems. See primary
volume and secondary volume.
replication snapshot A special type of snapshot, created by the remote replication feature, that preserves the
state of data of a replication set's primary volume as it existed when the snapshot was
created. For a primary volume, the replication process creates a replication snapshot on
both the primary system and, when the replication of primary-volume data to the secondary
volume is complete, on the secondary system. Replication snapshots are unmappable and
are not counted toward a license limit, although they are counted toward the system's
maximum number of volumes. A replication snapshot can be exported to a regular,
licensed snapshot. See also replication sync point.
replication sync point The state of a replication snapshot whose corresponding primary or secondary snapshot
exists and contains identical data. For a replication set, four types of sync point are
identified: the only replication snapshot that is copy-complete on any secondary system is
the “only sync point”; the latest replication snapshot that is copy-complete on any
secondary system is the “current sync point”; the latest replication snapshot that is
copy-complete on all secondary systems is the “common sync point”; a common sync point
that has been superseded by a new common sync point is an “old common sync point.”
repurpose A method by which all data on a system or disk is erased in an FDE-capable system.
Repurposing unsecures the system and disks without needing the correct passphrase. See
also FDE and passphrase.
SAS Serial Attached SCSI interface protocol or disk-drive architecture.
SC Storage Controller. A processor (located in a controller module) that is responsible for RAID
controller functions. The SC is also referred to as the RAID controller. See also EC and MC.
SCSI Enclosure Services See SES.
secondary volume The volume that is the destination for data in a replication set and that is not accessible to
hosts. For disaster recovery purposes, if the primary volume goes offline, a secondary
volume can be designated as the primary volume. The secondary volume exists in a
secondary vdisk in a secondary (or remote) storage system.
The contents of a secondary volume are in a constant state of flux and are not in a
consistent state while a replication is in process. Only snapshots that are associated with a
secondary volume are data consistent.
secret For use with CHAP, a password that is shared between an initiator and a target to enable
authentication.
secure hash algorithm See SHA.
secure shell See SSH.
Secure Sockets Layer See SSL.
SED Self-encrypting drive. A disk drive that provides hardware-based data encryption and
supports use of the storage system’s Full Disk Encryption feature. See also FDE.
SEEPROM Serial electrically erasable programmable ROM. A type of nonvolatile (persistent if power
removed) computer memory used as FRU ID devices.
Self-Monitoring
Analysis and Reporting
Technology
See SMART.