Dell PowerVault 735N (Rackmount NAS Appliance) - Manual (Page 58)

6-4 System Administrator’s Guide
Quiescent Period:
Prior to starting a snapshot, the system waits for a period of relative inactivity on the
volume being imaged. The default value for this period allows systems to start an
image with a consistent file set and a minimal time-out. Experienced administrators
may reduce or increase this value for system optimization. Reducing the quiescent
period allows snapshots to begin on systems where disk inactivity is rare, at the pos-
sible expense of synchronization problems within applications that are concurrently
writing to multiple files.
Quiescent Time-Out:
Specifies the amount of time the server should wait to retry starting a snapshot. A
snapshot will not start until a period of relative inactivity, specified by the Quiescent
Period, occurs. If an interval longer than Quiescent Time-Out passes before the
snapshot can begin, the snapshot will not be taken.
Cache Full Warning Threshold:
Defines the percentage of cache space used that will trigger warning messages to
the system event log.
Begin Snapshot Deletions:
Defines the percentage of cache space used that will trigger automatic deletion of the
oldest snapshots on the system. Automatic snapshot deletions are recorded in the
system log.
Cache Size:
Specifies the amount of space allocated to the cache file. Increasing this value will
allow more and larger snapshots to be maintained. Ensure that adequate space is
available on the snapshot files location drive.
Snapshot Files Location:
Specifies the server volume that will contain the cache data files. This file contains an
exact image of all data file values that have been preserved as part of a snapshot. You
should alter the default value only if the number, type, or capacity of storage disks has
been altered.
NOTE: When changing the location of the snapshots files, the previous files may not
be removed. To regain the space used by those files, manually delete those files from
the previous location.
Snapshot Directory Name:
Specifies the directory name which will be used for the snapshot mount point. Each
snapshot image appears as subdirectories of the volume which is being imaged. The
entire content of the volume as it existed when the snapshot was created appears
under this directory.