Volumes
58
SnapServer Administrator Guide
them). The security model determines the file-level security scheme that will apply
to files and folders within the volume or SnapTree directory.
Configuring Write Cache
Note
Not related to write cache on iSCSI disks. For information about configuring
write cache on iSCSI disks, see “Write-Cache Options with iSCSI Disks” on page 89.
By default, write cache is enabled on all volumes. For systems that do not use a UPS
device to help protect data during a power outage or for applications that require
synchronous writes to disk, write cache can be disabled on a volume by volume
basis. When a volume’s write cache is disabled, all data written to the volume
bypasses memory buffers and writes directly to disk, helping to protect the data
when writes are occur during a power outage. While disabling write cache does
help protect data, it also significantly impacts disk write performance. For the
procedures to disable write cache on new and existing volumes, see To Disable/
Enable Write Cache on a New Volume or To Disable/Enable Write Cache on an
Existing Volume.
Note
When write cache is disabled on a volume, disk cache is also disabled on all
disk drives that are members of the RAID or RAID group hosting the volume. This
can impact performance on other volumes with write cache enabled that are hosted
by the same RAID or RAID group.
Note
Not all disk drives support disabling write cache. If any of the volume’s
drives are IDE drives, you will not have the option to disable write cache for that
volume. In addition, write cache can not be disabled on SnapServer 18000 or the
SD30 expansion unit.
Checking Filesystems
Filesystems on individual volumes can be checked for errors and repaired, if
necessary. The root volume can also be checked, and any errors found will
automatically be repaired. Since the GuardianOS automatically checks the root
volume for errors if any of a number of triggers occurs (e.g., a power outage, failure
of the volume to mount, etc.), it is recommended that the root filesystem check
feature only be used when directed by a Technical Support representative. See the
Volumes section in the Online Help for procedures to check the volume filesystems.
Summary of Contents for 5325301507 - Snap Server 4400 NAS
Page 2: ......
Page 12: ...xii SnapServer Administrator Guide ...
Page 16: ...xvi SnapServer Administrator Guide ...
Page 58: ...Print Server 42 SnapServer Administrator Guide ...
Page 64: ...NIS Domain 48 SnapServer Administrator Guide ...
Page 110: ...Configuring VSS VDS for iSCSI Disks 94 SnapServer Administrator Guide ...
Page 154: ...Log View 138 SnapServer Administrator Guide ...
Page 228: ...Phone Home Support 212 SnapServer Administrator Guide ...