Dell MD3200i, MD3220i Virtual Disk Migration and Disk Roaming

48 Planning: MD3200i Series Storage Array Terms and Concepts

NOTE: Setting a high priority level impacts storage array performance. It is not

advisable to set priority levels at the maximum level. Priority should also be

assessed in terms of impact to host server access and time to complete an

operation. For example, the longer a rebuild of a degraded virtual disk takes, the

greater the risk for potential secondary disk failure.

Virtual Disk Migration and Disk Roaming

Virtual disk migration is moving a virtual disk or a hot spare from one array to

another by detaching the physical disks and re-attaching them to the new

array. Disk roaming is moving a physical disk from one slot to another on the

same array.

You can move virtual disks from one array to another without taking the

target array offline. However, the disk group being migrated must be offline

prior to performing the disk migration. If the disk group is not offline prior to

migration, the source array holding the physical and virtual disks within the

disk group marks them as missing. However, the disk groups themselves

migrate to the target array.

An array can import a virtual disk only if it is in an optimal state. You can

move virtual disks that are part of a disk group only if all members of the disk

group are being migrated. The virtual disks automatically become available

after the target array has finished importing all the disks in the disk group.

When you migrate a physical disk or a disk group from one MD3200i array to

another, the MD3200i array you migrate to, recognizes any data structures

and/or metadata you had in place on the migrating MD3200i array. However,

if you are migrating from any device other than a MD3200i Series Storage

Array, the MD3200i array does not recognize the migrating metadata and

that data is lost. In this case, MD3200i initializes the physical disks and mark

them as unconfigured capacity.

NOTE: Only disk groups and associated virtual disks with all member physical disks

present can be migrated from one storage array to another. It is recommended that

you only migrate disk groups that have all their associated member virtual disks in

an optimal state.

NOTE: The number of physical disks and virtual disks that a storage array supports

limits the scope of the migration.

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