Setting Data Resiliency - HP Surestore Disk Array 12h - And FC60 System Administrator Manual

Using the ARM Command Line Utilities for Windows NT
Viewing the Disk Array General Configuration Settings

Setting Data Resiliency

The data map contents stored in the disk array controller NVRAM is copied to two disks on the array at
regular intervals to protect against map loss. The interval at which the disks are updated with recovery map
information is controlled using the data resiliency setting. Selecting a data resiliency setting involves
making a tradeoff between data protection and performance. The more frequently the recovery maps are
updated, the more impact it may have on performance.
To set the data resiliency mode, type:
arraymgr -J {SingleController | Secure | Normal | HighPerformance} <array-id>
The data resiliency settings are described in Table 32.
Setting
SingleController This setting should only be used if the disk array is operating with one
controller. This suppresses the single controller warning messages that
are normally generated when the disk array is operating with one
controller. This setting will affect I/O performance. This is the default
setting for single controller mode.
Secure Continually updates the disks with any changes in the controller maps.
This is the highest level of data protection, but it may result in
decreased I/O performance.
Normal Updates the maps on the disks at regular intervals (typically 4 seconds).
This option offers both data protection and good performance. This is
the default setting for dual controller mode.
HighPerformance Updates the disk maps only during shutdown of the disk array. This is
the lowest level of data protection, but it offers the highest level of
performance.
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Table 32. Data Resiliency Settings
Description