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Disk Pools
Faster reconstruction of data
– Disk pools do not use hot spare drives for data
protection like a volume group does. Instead of hot spare drives, disk pools use
spare capacity within each drive that comprises the disk pool.
In hot spare drive coverage, the maximum drive IOPS limits the speed of
reconstruction of data from the failed drive to the hot spare drive. In a disk pool,
the reconstruction of data is much faster because the spare capacity in all of the
drives that comprise the disk pool is used. Additionally, the data to reconstruct
after a drive failure is reduced because the data is spread randomly across more
drives in a disk pool.
Faster reconstruction of data in a disk pool also reduces the risk of additional
drive failures during a reconstruction operation. For example, consider a drive
failure in a RAID Level 5 volume group that is comprised of three drives. The
time it takes to reconstruct the data from the failed drive is relatively longer for a
volume group. During the reconstruction of data, if another drive fails in this
volume group, data loss occurs. Unlike volume groups, the time for which the
disk pool is exposed to multiple drive failures during a reconstruction operation is
significantly reduced.
Reduced maintenance
– You can configure the storage management software to
send alert notifications when the configured capacity of a disk pool is reaching a
specified percentage of free capacity. Additionally, you do not need to manage
any hot spare drives. You can replace a set of drives during a scheduled
maintenance of the storage array.
Disk Pool Restrictions
Dynamic Segment Sizing (DSS) is not supported for disk pools.
You cannot change the RAID level of a disk pool. The storage management
software automatically configures disk pools as RAID level 6.
You cannot export a disk pool from a storage array or import the disk pool to a
different storage array.
All drive types (Fibre channel, SATA, SAS) in a disk pool must be the same.
All drive media types in a disk pool must be the same. Solid State Disks (SSDs)
are not supported.
You can protect your disk pool with Full Disk Encryption (FDE), but the drive
attributes must match. For example, FDE-enabled drives cannot be mixed with
FDE-capable drives. You can mix FDE-capable and non FDE-capable drives, but
the encryption abilities of the FDE drives cannot be used.
You can use Data Assurance (DA) capabilities of a drive set in a disk pool if all
drives match in their DA capabilities. However, you can use a drive set with
mixed attributes, but the DA capabilities of the drive can not be used.
If you downgrade the controller firmware version of a storage array that is
configured with a disk pool to a firmware version that does not support disk
pools, the volumes are lost and the drives are treated as unaffiliated with a disk
pool.
Summary of Contents for InfiniteStorage 4000 Series
Page 34: ...22 ExitStatus ...
Page 48: ...36 Adding Comments to a Script File ...
Page 110: ...98 Starting Stopping and Resuming a Snapshot Legacy Rollback ...
Page 168: ...156 Interaction with Other Premium Features ...
Page 182: ...170 Interaction with Other Premium Features ...
Page 192: ...180 SSD Cache Management Tasks ...
Page 216: ...204 RecoveryOperations ...
Page 218: ...206 Show Storage Array ...
Page 219: ...Appendix A Examples of Information Returned by the Show Commands 207 ...
Page 220: ...208 Show Storage Array ...
Page 221: ...Appendix A Examples of Information Returned by the Show Commands 209 ...
Page 222: ...210 Show Storage Array ...
Page 223: ...Appendix A Examples of Information Returned by the Show Commands 211 ...
Page 224: ...212 Show Storage Array ...
Page 225: ...Appendix A Examples of Information Returned by the Show Commands 213 ...
Page 226: ...214 Show Storage Array ...
Page 227: ...Appendix A Examples of Information Returned by the Show Commands 215 ...
Page 228: ...216 Show Storage Array ...
Page 229: ...Appendix A Examples of Information Returned by the Show Commands 217 ...
Page 230: ...218 Show Storage Array ...
Page 231: ...Appendix A Examples of Information Returned by the Show Commands 219 ...
Page 233: ...Appendix A Examples of Information Returned by the Show Commands 221 ...
Page 234: ...222 Show Controller NVSRAM ...
Page 253: ...Appendix A Examples of Information Returned by the Show Commands 241 ...
Page 254: ...242 ShowDrive ...
Page 255: ...Appendix A Examples of Information Returned by the Show Commands 243 ...
Page 256: ...244 ShowDrive ...
Page 257: ...Appendix A Examples of Information Returned by the Show Commands 245 ...
Page 258: ...246 ShowDrive ...
Page 268: ...256 ConfigurationUtility ...
Page 275: ......
Page 276: ...Copyright 2012 NetApp Inc All rights reserved ...