Disk Roaming - D-Link DSN-6120 User Manual

For example, there are two or more snapshots existed on a VD and the latest snapshot
keeps growing. When it comes to the moment that the snapshot space is 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.
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.
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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