IBM DS3950, Руководство пользователя и инструкция по установке

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v
Which method most closely matches the recommended drive upgrade procedure
that is provided in the operating system or the storage-management software
documentation.
v
Which RAID level is used on the affected drives. (RAID 0 requires you to
replace all the drives at the same time.)
v
How much downtime is acceptable as you swap the E-DDMs.
v
The number of E-DDMs in an array. Replacing E-DDMs one at a time is better
suited for arrays consisting of 3 to 5 E-DDMs. If you have more than 10
E-DDMs, consider replacing all of them at the same time.
v How much risk of losing data is acceptable. Because the array will be in a
degraded state during the RAID array reconstruction and copyback process as
result of replacing an E-DDM in the array, any new E-DDM failure will cause
the array to fail (causing a loss of data availability and even a loss of data). The
duration of the reconstruction and copyback process can be quite long,
depending on the size of the RAID array.
v
How extensive are the changes to the data while the array is in a degraded state
during the RAID array reconstruction and copyback process as result of
replacing an E-DDM in the array. The more extensive the data changes, the more
work that will need to be performed to restore the data in the event that the
array failed because of an additional E-DDM failed while the array is in
degraded state.
Replacing all E-DDMs at the same time
Use this procedure to replace all E-DDMs at the same time. You must use this
method if you are upgrading E-DDMs containing RAID 0 logical drives. All the
data currently on the E-DDMs is lost when you replace them; therefore, you must
back up all data that is currently on the E-DDMs. This procedure also requires you
to turn off the EXP395 and the DS3950, which makes the storage subsystem (and
any attached storage expansion enclosures) inaccessible to other users.
To replace all the E-DDMs at the same time, perform the following steps:
1. Read the following information:
v The information in “Replacing multiple E-DDMs” on page 73, particularly
the paragraphs that discuss the differences between the two possible
upgrade procedures
v
The information in your software documentation regarding E-DDM
upgrades and installation
v
The documentation that comes with the new E-DDMs
Read all precautionary notes, kit instructions, and other information. Kit
instructions often contain the most current information regarding the
E-DDMs and their installation, plus upgrade or servicing procedures.
Compare the kit instructions with this procedure to determine if you need
to modify this procedure.
2. Use the DS Storage Manager software to check the status of the storage
subsystem. Correct any problems that are reported. Upgrade the storage
subsystem controller to the level that supports the new E-DDMs, if required.
3.
Perform a complete backup of the E-DDMs that you are replacing.
You need the backup to restore data on the E-DDMs later in this procedure.
Attention: When you handle static-sensitive devices, take precautions to
avoid damage from static electricity. For details about handling static-sensitive
devices, see “Handling static-sensitive devices” on page 22.
4. Unpack the new E-DDMs.
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IBM System Storage DS3950 EXP395 Storage Expansion Enclosure: Installation, User’s, and Maintenance Guide