IBM DS8700, Введение и руководство по планированию

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The online Information Center is an information database that provides
you with the opportunity to quickly familiarize yourself with the major
aspects of the DS8000 series and to easily recognize the topics for which
you might require more information. It provides information regarding
user assistance for tasks, concepts, reference, user scenarios, tutorials, and
other types of user information. Because the information is all in one place
rather than across multiple publications, you can access the information
that you need more efficiently and effectively.
For the latest version of the online Information Center, go to
http://publib.boulder.ibm.com/infocenter/dsichelp/ds8000ic/index.jsp
Limitations
The following list describes known limitations for DS8000 storage units:
v
For the Dynamic Volume Expansion function, volumes cannot be in Copy
Services relationships (point-in-time copy, FlashCopy SE, Metro Mirror, Global
Mirror, Metro/Global Mirror, and z/OS Global Mirror) during expansion.
v The size limit for single volumes in a Copy Services relationship is 2 TB. This
limit does not apply to extents (when part of multiple volumes).
v
The amount of physical capacity within a 242x system that can be logically
configured for use is enforced by the 242x Licensed Machine Code to maintain
compliance with the extent of IBM authorization established for licensed
functions activated on the machine.
v
The deactivation of an activated licensed function, or a lateral change or
reduction in the license scope, is a nondisruptive activity that occurs at the next
machine IML. For example:
–
A lateral change is defined as changing the license scope from FB to CKD or
from CKD to FB.
– A reduction is defined as changing the license scope from ALL to FB or from
ALL to CKD.
v The following activities are disruptive:
– Addition of the Earthquake Resistance Kit feature 1906. This feature is not
supported on the DS8700 but is supported on the DS8800.
– Removal of an expansion model from the base model. Data is not preserved
during this activity.
v Some DS8000 series functions are unavailable or are not supported in all
environments. Go to the
System Storage Interoperation Center (SSIC) website at
www.ibm.com/systems/support/storage/config/ssic for the most current
information on supported hosts, operating systems, adapters, and switches.
v
Plant configured systems with Encryption Drive Set support (feature number
1751) can support a field installation of encrypted drives. Existing DS8000
systems or systems lacking the encryption drive set support feature cannot
support encryption drive sets.
v In a DS8700, 8 drives are the minimum number of SSDs (RAID-5 only) that are
supported. A single DDM failure in a minimum configuration will trigger the
call home feature.
v SSD drive sets are not supported in RAID-6 or RAID-10 configurations.
v
Nearline SAS drives are not supported on RAID-5 and RAID-10 configurations.
v In a tiered extent pool (with Enterprise and SSD drives), Extent Space Efficient
(ESE) volumes cannot allocate extents to SSD ranks.
v
Conversions between warranty machine types are not supported.
Chapter 1. Introduction to IBM System Storage DS8000 series
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