IBM Advanced SerialRAID Adapters SA33-3285-02, User Manual

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fw_max_length (default=128)
This attribute sets the maximum size, in blocks, of write operations to the
fast-write cache. Write operations that are larger than the specified value write
data directly to the disk, and do not use the fast-write cache.
force=yes/no
If a disk is using a fast-write cache that is failing, you must specify this
attribute as yes to allow the fast-write cache to be disabled.
Action Attributes (RAID-1, RAID-5, and RAID-10 Only)
You can specify the following attributes with the -a option when you are using the
ssaraid command with the
-A
and
-i
exchange options to do maintenance on an array.
new_member=disk
This attribute specifies the disk drive that is to be added to the array, either in
exchange for a failing disk drive that has caused the array to enter the
Exposed state, or in exchange for a disk drive that the old_member attribute
has specified.
old_member=disk
This attribute specifies the member disk drive that is to be removed from the
array. You can use the attribute on its own, or with the new member attribute.
Use the old_member attribute on its own if you want only to remove the disk
drive from the array.
Use the old_member attribute and the new_member attribute together if you
want to exchange the disk drives in one action, and the subsystem has a
spare slot available for the new disk drive.
If no spare slot is available, use the following method to exchange the disk
drives:
1. Logically remove the failing disk drive. For this action, use the ssaraid
command with only the old_member attribute specified.
2. Physically remove the disk drive from the slot.
3. Install the new disk drive into the slot that contained the old disk drive.
4. Logically add the new disk drive to the array. For this action, use the
ssaraid command with only the new_member attribute specified.
Notes:
1. If you specify the new_member attribute and the old_member attribute together,
an in-place exchange is attempted; the old_member disk drive is replaced by the
new_member disk drive in one operation.
2. You can remove disk drives only from arrays that are not in the Exposed state.
When you remove a disk drive, the array enters the Exposed state, and remains in
that state until you add the new disk drive.
3. RAID-5 arrays cannot operate if they lose more than one disk drive at a time.
4. To generate a list of suitable exchange candidates, use the -x flag with the list
command.
Chapter 12. Using the SSA Command Line Interface for RAID Configurations
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