• Yes. All virtual disks that underlie the host volume comply with snapclone g uidelines. Snapclone
replication can be per formed.
• No. One or more virtual disks that un derlie the host volume do not comply with snapclone
guidelines. Snapclone replication cannot be performed.
See also virtual disks snapclones, snapclone FAQ and snapclone guidelines.
Snapshots (host volume)
Snapshot replication of a host volume instantly cre ates a virtual, point-in-time copies of the virtual disks
that underlie a host volume. The copies are called snapshots.
Thesnapshotp
ropert y indicates whether the host volume can be locally replicated using the snapshot
method. Values are:
• Yes. All virtual disks that underlie the host volume comply with snapshot guidelines. Snapshot
replication can be per formed.
• No.Oneormor
e virtual disks that underlie the host volume do not comply with snapshot
guidelines. Snapshot replication cannot be performed.
See also virtual disks snapshots, snapshot types, snapshot FAQ and snapshot guidelines.
Snapshot FAQ
• How can I tell a snap shot from other types of virtual disks?
Because snapshots are not independent virtual disks, they are identified differently than original
virtual disks. See virtual disks types.
• How long does it take to c reate a snapshot?
A snapshot requires only a matter of seconds, no ma tter how large the original virtual disk.
• If it is virtual, can a host write to a snapshot?
Yes. A snapshot is functionally equivalent to a physical disk with both read and write capability.
• After I create a snapshot, can I delete the original virtual disk?
No. A snapshot always relies, at least in part, on the original (active) virtual disk for data. If the
original virtual disk is deleted, its associated snapshot becomes unusable. A snapshot should
be thought of as a temporar y copy.
• Can I make multiple snapshots of an original virtual disk?
Yes. H owever, there i s a limit. See virtual disks snapshot guidelines.
• What is t he maximum nu mber of snapshots on a storage system?
There is no limit. However, the greater the number of snapshots, the longer it takes to shut down
the storage system du ring maintenance and upgrade activities.
• Can I create a snapshot of a snapclone?
Yes.
• Can I create an snapshot of a snapshot?
No.
Snapshot types (allocation policy)
Snapsho
t types (allocation policy) specifies how the storage system allocates space in a disk group
for a sna
pshot. Values are:
• Dema nd a llocated. The space reserved for the snapshot can automatically change from a n initial
minimum amount, up to the full capacity of the original virtual disk.
• Fully allocated. The space reserved for the snapshot is initially set to, and remains fixed at, the full
capaci
tyofthesourcevirtualdisk.
When selecting a snapshot type, one consideration is the lifetime of the snapshot and the amount of
source d a ta that will change d uring its lifetime.
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