HP 418800-B21 - StorageWorks Modular Smart Array 70 Storage Enclosure, User Manual

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Method Flush implementation Write cache setting after replication
GUI action
The replication manager automatically sets
the source disk to write-though mode and
ensures the fl ush is completed before starting
the replication.
Job
You must include job commands to set the
source disk to write-through mode and wait
for the fl ush to complete before starting the
replication.
CLUI
You must issue CLUI commands to set the
source disk to write-through mode and wait
for the fl ush to complete before starting the
replication.
When replication is completed, the controller
software automatically sets the source disk
and preallocated copy (converted container)
to write-back mode.
If you want the source disks or copies to be
in write-through mode, you must explicitly
set them.
This feature is controller-software version dependent. See controller software features - local replication .
See also virtual disk containers .
Snapclone FAQ
• How can I tell a snapclone from other types of virtual disks?
Because snapclones are independent virtual disks, they are identi fi ed as original (active) virtual
disks. This distinguishes them from snapshots, but not from other independent virtual disks.
See virtual disks types .
• How long does it take to create a snapclone?
A snapclone requires only a matter of seconds to create, no matter how large the source. However,
the snapclone does not become an independent virtual disk until unsharing is completed.
• What is snapclone normalization or unsharing?
Normalization or unsharing is a snapclone background process. See virtual disks normalization .
• When can a host read from or write to a snapclone?
A host can immediately read from and write to a snapclone, even during the unsharing process.
• After I create a snapclone, can I delete the source virtual disk?
Yes. However, you cannot delete the source virtual disk until the background unsharing process is
completed. Once the snapclone is an independent virtual disk, you can delete the source.
Snapclone guidelines
The following guidelines apply to snapclone virtual disks:
• The array must have a local replication license. See replication licenses overview .
• A snapclone can be in a different disk group than the source. (A snapclone is created in the
same disk group as its source, unless speci fi ed otherwise.)
• The redundancy (Vraid) level of a snapclone can be the same, lower, or higher than the source.
See redundancy level (Vraid) .
• Until a snapclone is normalized, another snapclone of the same source cannot be created. See
normalization .
Snapclones cannot be created when the disk to be replicated is:
• A snapshot
• A disk that has a snapshot
• In the process of normalizing or being deleted
Snapshots
Snapshot replication of a virtual disk instantly creates a virtual, point-in-time copy of the disk. The copy is
called a snapshot. See also virtual disks snapshot types and snapshot FAQ .
HP StorageWorks Replication Solutions Manager 4.0.1
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