Proactive Avoidance; Checking Disk Infrastructure; Powershell Screen - HP BL860c Management Manual

Proactive Avoidance

This section provides information on how to avoid the System hive 32 MB limit as well as how
to install the HP Registry Monitor Service, which provides alerts when the limit is near.

Checking Disk Infrastructure

Typically the biggest contributor to hive usage is the amount of disks and number of paths to
those disks. Administrators should know how many disks and paths a system has, and it's also
a good idea to check how many are in the Registry, since a number of stale paths may exist. These
are not removed when disks are deleted.
The best way to check the amount of registry entries is with a few simple commands in PowerShell.
PowerShell has Registry Provider, which displays the registry in a folder structure. Administrators
are used to navigating with the cd and dir commands, as well as the Tab key for folder
completion. The Registry is indicated as "HKLM:", where the colon serves to make it act like a
disk. From PowerShell, the command dir hklm:\system lists all of the subkeys, such as the
ControlSets.
Using this information, it is possible to see how many disks the system recognizes by entering
the following three commands:
dir hklm:\System\ControlSet001\Enum\SCSI
dir hklm:\System\ControlSet001\Enum\STORAGE
dir hklm:\System\ControlSet001\Enum\MPIO
Figure 11 is an example of the output of these commands, with PowerShell finding a large number
of disks:
Figure 1 1 PowerShell screen
The output above shows there are currently 156 drives in the database (the MPIO) key, but the
amount of SCSI disks recognized is 524, with a total of 787 Volumes. The MPIO key is the most
useful since it only records one instance of the path to a disk. This means the Administrator can
expect to see 156 drives (plus any local disks). The fact there are 524 SCSI disks is merely a
representation of the MPIO disks with all of the paths enumerated. A cursory glance shows that
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