Ds8000 Series Limitations - IBM DS8000 User Manual

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DS8000 series limitations

maximum supported sizes. DS8000 and z/OS limit CKD extended address
volumes sizes. A 3390 Model A volume has the capacity of 1 - 262668 cylinders
(approximately 223.2 GB maximum).
z/VM and z/OS software are required to use extended address volumes. Volume
creation and volume expansion is limited to 3390 Model 9 sizes if earlier software
has a path group on the DS8000. Volumes larger than 3390 Model 9 do not come
online if earlier z/OS software is in use.
The following list describes known limitations for the DS8000 series.
v The 65 520 cylinder 3390 volume is not supported with z/OS Global Mirror.
v The IBM FlashCopy SE function is not supported in DS8000 machines that have
a 3rd and 4th expansion unit attached.
For the Dynamic Volume Expansion function, volumes cannot be in Copy
v
Services relationships (point-in-time copy, FlashCopy SE, Metro Mirror, Global
Mirror, Metro/Global Mirror, and z/OS Global Mirror) during expansion.
v The amount of physical capacity within a 2107/242x system that can be logically
configured for use will be enforced by the 2107/242x licensed machine code
(LMC) to maintain compliance with the extent of IBM authorization established
for licensed functions activated on the machine. The 2107/242x LMC will not
allow the logical configuration of physical capacity beyond the extent of IBM
authorization (except when activating Standby CoD capacity).
v The 500 GB FATA 7 200 rpm disk drives support various fixed content, data
archival, reference data, and near-line applications that require large amounts of
data at low cost. They are not intended for use in applications that require drive
duty cycles greater than 20%. To intermix the FATA disk drive sets and
fibre-channel disk drive sets is not supported within a disk enclosure or at
creation. However, intermixing on the same DA loop of enclosures with different
drive types is supported if the drives within each enclosure are the same.
v The deactivation of an activated licensed function, a lateral change, and the
reduction in the license scope are all disruptive activities and require a machine
IML (Models 921, 922, 931, and 932) or reboot of the affected image (Model 9A2
and 9B2). A lateral change is defined as changing the license scope from fixed
block (FB) to count key data (CKD) or from CKD to FB. A reduction is defined
as changing the license scope from all physical capacity (ALL) to only FB or only
CKD capacity.
v The following activities are disruptive:
– Addition of the Earthquake Resistance Kit feature 1906.
– Addition of the 150x POWER5+
– All model conversions. In addition, data is not preserved during the model
conversion unless the conversion is 921/931.
– Field attachment of the first expansion (Model 92E) to a base (Model 922 or
932).
– Field attachment of the first expansion (Model 9AE) to a base (Model 9A2 or
9B2).
– Removal of an expansion model from the base model. Data is not preserved
during this activity.
v Some DS8000 series functions are not available or supported in all environments.
You can find current information about supported environments, prerequisites,
and minimum operating systems levels at the following IBM Web site:
™
features.
Chapter 1. Introduction to IBM System Storage DS8000 series
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