776 Implementing the IBM Storwize V7000 with IBM Spectrum Virtualize V8.2.1
Event ID
An event ID is a value that is used to identify a unique error condition that was detected by the 
Storwize V7000. An event ID is used internally in the cluster to identify the error.
Excluded condition
The excluded condition is a status condition. It describes an MDisk that the IBM Storwize 
V7000 decided is no longer sufficiently reliable to be managed by the cluster. The user must 
issue a command to include the MDisk in the cluster-managed storage. 
Extent
An extent is a fixed-size unit of data that is used to manage the mapping of data between 
MDisks and volumes. The size of the extent can range 16 MB - 8 GB.
External storage
External storage refers to MDisks that are SCSI logical units that are presented by storage 
systems that are attached to and managed by the clustered system.
Failback
Failback is the restoration of an appliance to its initial configuration after the detection and 
repair of a failed network or component.
Failover
Failover is an automatic operation that switches to a redundant or standby system or node in 
a software, hardware, or network interruption. See also Failback.
Feature activation code
An alphanumeric code that activates a licensed function on a product.
Fibre Channel port logins
FC port logins refer to the number of hosts that can see any one V7000 port. The IBM 
Storwize V7000 has a maximum limit per node port of FC logins that are allowed. 
Field-replaceable unit
Field-replaceable units (FRUs) are individual parts that are replaced entirely when any one of 
the unit’s components fails. They are held as spares by the IBM service organization. 
FlashCopy
FlashCopy refers to a point-in-time copy where a virtual copy of a volume is created. The 
target volume maintains the contents of the volume at the point in time when the copy was 
established. Any subsequent write operations to the source volume are not reflected on the 
target volume.
FlashCopy mapping
A FlashCopy mapping is a continuous space on a direct-access storage volume that is 
occupied by or reserved for a particular data set, data space, or file.
FlashCopy relationship
See FlashCopy mapping.