Guidelines For Creating Aggregates - IBM System Storage N Series Implementation Manual

Guidelines for creating aggregates

Restrictions on
mixing storage
types in an
aggregate
Considerations
when preserving
aggregates when
moving a shelf
Chapter 2: Planning for Using Disk Shelves with a Gateway
Data ONTAP does not support mixing different types of storage in the same
aggregate because it causes performance degradation. For example, you cannot
mix the following storage types in the same aggregate:
◆
Native disks and array LUNs
◆
Different types of disk drives
Note
Avoid mixing drives with different disk speeds in the same aggregate;
mixing drives of different speeds in the same aggregate directly affects disk
input/output operations per second and response time.
◆
Native disks with block checksum type and native disks with zoned
checksum type
◆
Array LUNs from Fibre Channel disks and array LUNs from SATA disks
◆
Array LUNs from storage arrays from different vendors
◆
Array LUNs from storage arrays from different families
Note
Storage arrays in the same family share the same characteristics. See the
gateway Implementation Guide for your vendor for information about how
the gateway defines family members for the vendor.
◆
Array LUNs from storage arrays with 4-Gb HBAs and LUNs from storage
arrays with 2-Gb HBAs
Example: The following command creates an aggregate called vs23b_vol1 with
the same type of storage in it—four FCAL disks on systems running Data
ONTAP 8.0 7-Mode and 7.x releases:
aggr create vs23b_vol1 -T FCAL -n 4
Data ONTAP does not support duplicate aggregate and volume names on the
same system. If you want to preserve the data on a disk shelf you are moving to
the gateway, check the aggregate and volume names on the disk shelf and
gateway for duplicates before you move the disk shelf. If you discover aggregate
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