Administrator Guide

Table 43. Glossary of ME4 Series terms (continued)
Term Definition
quick rebuild A virtual-storage feature that reduces the time that user data is less than fully fault-tolerant after a
disk failure in a disk group. The quick-rebuild process rebuilds only data stripes that contain user data.
Data stripes that have not been allocated to user data are rebuilt in the background.
RAID head See controller enclosure.
RBOD “RAID bunch of disks.” See controller enclosure.
read cache A special disk group, comprised of SSDs, that can be added to a virtual pool for the purpose of
speeding up read access to data stored on spinning disks elsewhere in the pool. Read cache is also
referred to as read flash cache.
read flash cache See read cache.
recovery In an active-active configuration, recovery is the act of returning ownership of controller resources to
a controller which was offline from its partner controller. The resources include volumes, cache data,
host ID information, and LUNs and WWNs. See also read cache.
remote syslog support See syslog.
replication Asynchronous replication of block-level data from a volume in a primary system to a volume in a
secondary system by creating an internal snapshot of the primary volume and copying the snapshot
data to the secondary system via Fibre Channel or iSCSI links.
replication set For virtual replication, a container that houses the infrastructure upon which replications are
performed. It defines a relationship between a primary and secondary volume for the purposes of
maintaining a remote copy of the primary volume on a peer system. See primary volume, secondary
volume.
replication snapshot history As part of handling a replication, the replication set will automatically take a snapshot of the primary
and/or secondary volume, thereby creating a history of data that has been replicated over time. This
feature can be enabled for a secondary volume or for a primary volume and its secondary volume, but
not for a volume group.
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, passphrase.
RFC Read flash cache. See read cache.
SAS Serial Attached SCSI.
SBB Storage Bridge Bay. A specification that standardizes physical, electrical, and enclosure-management
aspects of storage enclosure design.
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, MC.
secondary system The storage system that contains a replication set’s secondary volume. See also replication set,
primary system.
secondary volume The volume that is the destination for data in a replication set and that is not accessible to hosts. The
secondary volume exists in a secondary (linear storage) or pool (virtual storage) in a secondary
storage system.
secret For use with CHAP, a password that is shared between an initiator and a target to enable
authentication.
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.
SES SCSI Enclosure Services. The protocol that allows the initiator to communicate with the enclosure
using SCSI commands.
SFCB Small Footprint CIM Broker.
SFF Small form factor.
Glossary of terms 177