IBM N Series, Руководство по внедрению

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36 General requirements when adding a disk shelf
General requirements when adding a disk shelf
Minimum Data
ONTAP requirement Before you add a disk shelf to your gatewayData ONTAP 7.3 or higher.
Loop speed
requirements If you are adding a disk shelf to an existing gateway, be sure that you understand
the characteristics of the disk shelf—including its speed. The output from the
sysconfig -a
command provides information about the loop speed of the disk
shelf.
Review the characteristics of the disk shelf models that are documented in the
guide for your disk shelf.
Attention
A common error in setting up disk shelves is a loop speed mismatch between
components on the same loop. The Gb-loop speed for all components—including
the disk shelves—must be set to the lowest speed of any component in the loop.
When there is a loop speed mismatch, an error message might be generated, the
gateway might panic, or the gateway might not be able to see the disks on the
disk shelf.
Availability of the
gateway while a
disk shelf is being
added You can add new disk shelves to a gateway without powering down the system.
(This is referred to as
hot-adding disk shelves .) While the disk shelf is being
added, the gateway can continue to access data on any existing disk shelves and
on the storage arrays that provide storage (array LUNs) for the gateways.
Attention
Hot-adding disk shelves enables you to add (but not swap) disk shelves without a
service interruption. However, you cannot add more disk shelves to your system
than it can support; for an HA pair, you cannot add more disk shelves than either
the entire configuration or either node can support.
Hot-adding a disk shelf is different from hot-swapping a disk shelf. Hot-
swapping a disk shelf, which means removing an existing disk shelf and
installing a new one in its place, is not supported. Your system supports hot-
adding of disk shelves only.