Editing mapping policies – HP XP Racks User Manual
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Cache Partition. Cache memory can be partitioned using Cache Partition to configure a cache
logical partition (CLPR) for the mapped volumes. Cache logical partitions are often used to
limit cache-use by accessing slower external storage volumes.
HP strongly recommends that you place external storage array groups in a CLPR other than
CLPR0. See the HP XP7 Cache Partition User Guide for detailed information on CLPR.
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Inflow Control. When the write operation to the external volume cannot be completed, Inflow
Control specifies whether the write operation to cache memory is limited (Enable) or continued
(Disable).
◦
If Enable is specified, the write operation to cache is limited and I/O from the host is not
accepted. Limiting the write operation prevents the accumulation of data that cannot
destage to cache memory.
◦
When Disable (the default) is specified, I/O from the host during the retry operation is
written to cache memory. When write operations to the external volume are again possible,
data in cache memory is written to the external volume (all data is destaged).
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ALUA mode (Use ALUA as Path Mode:Enable or Disable).
In the local storage system, you can select whether ALUA mode is used as the path mode. If
ALUA is supported in the profile information of the external storage, Enable is used by default.
Otherwise, Disable is used. For information on ALUA mode, see
path mode for external volumes” (page 23)
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Load Balance Mode. Select Depend on the selected external volume(s), Normal Round-robin,
Extended Round-robin, or Disable as a Load Balance Mode for the external storage system.
By default, Normal Round-robin is used. However, when the product name of the storage
system is displayed as “generic”, Depend on the selected external volume(s) is used by default..
If Single is set as the Path Mode or Disable is set for Use ALUA as Path Mode, Load Balance
Mode cannot be specified.
◦
Depend on the selected external volume(s): If Enable is set for ALUA Settable on the external
volume, Normal Round-robin is set for Load Balance Mode automatically. If Disable is set
for ALUA Settable, Disable is set for Load Balance Mode automatically.
◦
Normal Round-robin: I/O is distributed to several paths on which I/O operation is enabled
for the external storage system.
◦
Extended Round-robin: I/O is distributed to several paths on which I/O operation is
enabled for the external storage system. For sequential I/O, the external volume is divided
into sections at regular intervals. In this case, the same path is used for I/O within the
same section which reduces the frequency of I/O distribution.
◦
Disable: As in Single mode, I/O operation is performed using the path that has the highest
priority of all paths on which I/O operation is enabled for the external storage system.
Editing mapping policies
Required Role
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Storage Administrator (Provisioning)
1.
In Remote Web Console, click External Storages in the Storage Systems tree.
2.
Select the External Storage Systems tab.
3.
Select the row of the desire external storage system.
4.
Open the Edit Policies window in one of these ways.
- In the External Storage Systems tab, click Edit Policies.
- In the Actions tab, click Edit Policies.
Editing external volume policies (settings)
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