Serviceguard Extension for RAC Version A.11.20 Release Notes, April 2011

Mass Storage Stack at www.hp.com/go/hpux-core-docs —> HP-UX 11i v3 —> white
papers).
Migration involves modifying system and application configuration files and scripts to use persistent
device files, and in some cases, new commands and options. The process is described in the white
papers HP-UX 11i v2 to 11i v3 Mass Storage Stack Update Guide and LVM Migration from Legacy
to Agile Naming Model HP-UX 11i v3 at www.hp.com/go/hpux-core-docs —> HP-UX 11i
v3 —> white papers.
If you cold-install HP-UX 11i v3, sets of both legacy and persistent device files are automatically
created. In this case, by default, the installation process will configure system devices such as the
boot, root, swap, and dump devices to use persistent device files. This means that system
configuration files such as /etc/fstab and /etc/lvmtab will contain references to persistent
device files, but Serviceguard’s functioning will not be affected.
CAUTION: You cannot migrate to the agile addressing scheme during a rolling upgrade if you
are using cluster lock disks as a tie-breaker, because that involves changing the cluster configuration.
But under certain conditions, you can migrate the cluster lock device file names to the new scheme
without bringing the cluster down. For the requirements and a procedure, see the section “Updating
the Cluster Lock Configuration” in chapter 7 of the latest edition of Managing Serviceguard.
NOTE: It is possible, though not a best practice, to continue to use legacy DSFs on some nodes
after migrating to agile addressing on others. If necessary, this allows you to migrate different
nodes at different times.
For more information about agile addressing, see following documents at www.hp.com/go/
hpux-core-docs —> HP-UX 11i v3:
• HP-UX System Administrator's Guide: Logical Volume Management HP-UX 11i Version 3
(under User guide section)
• HP-UX 11i v3 Installation and Update Guide (under Setup and install - general section)
• white papers:
The Next Generation Mass Storage Stack◦
◦ HP-UX 11i v2 to 11i v3 Mass Storage Stack Update Guide
◦ HP-UX 11i v3 Native Multi-Pathing for Mass Storage
◦ LVM Migration from Legacy to Agile Naming Model HP-UX 11i v3
See also www.hp.com/go/hpux-core-docs —> HP-UX Manpages for HP-UX 11i v3.
Cluster-wide Device Special Files (cDSFs)
Because DSF names may be duplicated between one host and other, it is possible for different
storage devices to have the same name on different nodes in a cluster, and for the same piece of
storage to be addressed by different names. Cluster-wide device files (cDSFs), available as of the
September 2010 Fusion Release, ensure that each storage device used by the cluster (or any group
of nodes within the cluster that you specify) has a unique device file name.
IMPORTANT: To enable cDSF functionality in Serviceguard A.11.20, a patch (PHSS_41225 or
later) is required.
NOTE: cDSFs apply only to shared storage. They will not be generated for local storage, such
as root, boot, and swap devices.
HP recommends that you use cDSFs for the storage devices in the cluster because this makes it
simpler to deploy and maintain a cluster, and removes a potential source of configuration errors.
SGeRAC supports Cluster-wide Device Special File (cDSF) format. See below.
8 Serviceguard Extension for RAC Version A.11.20 Release Notes