User manual

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run out, the system will try to remove the oldest snapshot to release more space for
the latest snapshot usage. As the latest snapshot is growing, the system keeps
removing the old snapshots. When it comes that the latest snapshot is the only one
in system, there is no more snapshot space which can be released for incoming
changes, then snapshot will fail.
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How many snapshots can be created on a VD
There are up to 32 snapshots can be created on a UDV/VD. What if the 33rd
snapshot has been taken? There are two different situations:
1. If the snapshot is configured as auto snapshot, the latest one (the 33rd
snapshot) will replace the oldest one (the first snapshot) and so on.
2. If the snapshot is taken manually, when taking the 33rd snapshot will fail and a
warning message will be showed on Web UI.
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Rollback / Delete snapshot
When a snapshot has been rollbacked, the other snapshots which are earlier than it
will also be removed. But the rest snapshots will be kept after rollback. If a snapshot
has been deleted, the other snapshots which are earlier than it will also be deleted.
The space occupied by these snapshots will be released after deleting.
5.5 Disk roaming
Physical disks can be re-sequenced in the same system or move all physical disks in
the same RAID group from system-1 to system-2. This is called disk roaming.
System can execute disk roaming online. Please follow the procedures.
1. Select “/ Volume configuration / RAID group”.
2. Check the gray button next to the RG number; click “Deactivate”.
3. Move all PDs of the RG to another system.
4. Check the gray button next to the RG number; click “Activate”.
5. Done.
Disk roaming has some constraints as described in the followings:
1. Check the firmware version of two systems first. It is better that either systems
have the same firmware version or system-2 firmware version is newer.
2. All physical disks of the RG should be moved from system-1 to system-2
together. The configuration of both RG and VD will be kept but LUN
configuration will be cleared in order to avoid conflict with system-2’s original
setting.
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