Licensekey, deletelicensekey, Preferredpathmode, Readcache, writecache – HP SmartStart-Software User Manual

Page 42

Advertising
background image

Toolkit utilities 42

LicenseKey, DeleteLicenseKey

These options enable you to enter a 25-character license key to activate or uninstall some controller

features. Hyphens can be entered, but are not required.

PreferredPathMode

The setting that you select for this option determines how the preferred I/O path to a particular logical
drive is set for a redundant array controller that is in an active/active configuration.
Not all controllers support this feature, and controllers in an active/standby configuration disregard this

option.

Auto is the default setting for new configurations. In this case, the storage system automatically

selects the I/O path from the redundant controller to the logical drive and dynamically load
balances all paths.

Manual enables you to assign the logical drive to a specific redundant controller. If you select this
setting, use the PreferredPath (on page

46

) command to specify the path.

If you are reconfiguring a controller and do not specify a setting for this option, the existing setting
remains unchanged.

ReadCache, WriteCache

Enter a number between 0 and 100 to specify the percentage of cache that is to be allocated to drive

reads or writes. The default value for both options is 50.
The allowable cache ratios depend on the controller model and whether it has battery-backed write
cache, as described in the following table.
A "+" indicates that the specified cache ratio is allowed for that type of controller, while a "–" indicates
that the ratio is not allowed.

Read:write

ratio

RA4x00

with 16MB
cache

RA4x00

with 48MB
cache

All other controllers

with battery-backed
write cache

All other controllers

without battery-backed
write cache

100:0

+

+

+

+

90:10

+

+

80:20

+

+

75:25

+

70:30

+

+

60:40

+

+

50:50

+

+

+

40:60

+

30:70

+

25:75

+

+

0:50*

+

0:75*

+

0:100

+

* The cache ratio percentages do not total 100 in these cases because the additional 16-MB or 48-MB cache

modules are not used. Only the battery-backed write cache is used.

Advertising
This manual is related to the following products: