HP XP P9500 Storage - Manual (Page 162)

Notes on Using HDLM
This section contains notes that are important for running HDLM operations.
Using a Storage Management Program
You must not change the vendor ID and product ID of a storage system. If
you change these IDs, HDLM will not be able to recognize the storage
system.
Upgrading Windows
Always remove HDLM before upgrading or re-installing Windows, or before
installing a Windows Server 2003 service pack. If you upgrade or re-install
Windows without removing HDLM, HDLM might not be able to properly
manage paths after that because OS device drivers related to HDLM
operation are updated.
Note that once service packs become available for Windows Server 2012, you
will not need to uninstall HDLM before installing a Windows Server 2012
service pack.
Using MSCS
When the Number of Displayed Paths Is Less than the Actual Number of Paths
When displaying path information, the number of paths displayed might be
less than the actual number of paths. This occurs when one host uses an LU
exclusively, preventing other hosts from obtaining information about the
devices for that LU. When this is resolved and the information can be
obtained, the host will be able to display all the paths.
When a System Event Occurs in an MSCS Environment
When you start up a standby node, or when a standby node has recovered
from a path error, the following event is issued and output to the system
event log. However, this will not affect system operations:
Source: mpio
Event ID: 20
Description: A Path Verification request to a device on \Device
\MPIODiskn that is controlled by Hdlm Device-Specific Module has
failed. This may indicate a Path Failure.
This event occurs when the MPIO checks the disk before initializing it and the
standby node cannot use the LU because the active node is using it.
Using the EMC DMX series, EMC CX series, and HP EVA series
• The EMC DMX series, EMC CX series, and HP EVA series can be managed
by using the HDLM versions listed below.
¢
If the OS is Windows Server 2003:
4-2
HDLM Operation
Hitachi Dynamic Link Manager User Guide for Windows ®