Designing High Availability Solutions with HP Serviceguard and HP Integrity Virtual Machines

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Advantages of the SG-IVS toolkit:
• This toolkit uses Serviceguard package modules, so you can generate packages using the Serviceguard
cmmakepkg command. Additionally, the Serviceguard online package configuration change feature is supported.
• This toolkit will be supported with Integrity VM version B.04.30 and later.
• This toolkit will be enhanced to take advantage of future Integrity VM and Serviceguard features.
Disadvantages of the SG-IVS toolkit:
• This toolkit is not supported for creating packages using Integrity VM versions prior to B.04.30. This means there is
no support for VM guests running Windows or Linux.
Known issues when using the SG-IVS toolkit:
• If the VM guest backing store resides on storage using a volume manager, the cmdeployvpkg command expects
the volume manager to be activated so that the backing store is accessible on the node before you run the
command.
• The cmdeployvpkg command does not add appropriate entries to the package configuration file for VM guests
on CVM or CFS backing stores. After running the cmdeployvpkg command to the package, a guest that contains
CVM or CFS backing stores, can review and modify the package configuration. As part of this process, add CVM
and/or CFS backing store entries to these files.
• The cmdeployvpkg command with the –U option must be used to deconfigure a VM guest from a Serviceguard
package and delete the package, rather than using the Serviceguard cmdeleteconf command. This is necessary
to reconfigure the VM guest to be started and stopped using HPVM commands after deleting the package.
• The cmdeployvpkg command cannot be used for the easy deployment of a VM guest using an NFS backing
store. However, it is possible to create a package configuration for VM guests using an NFS backing store by
using the cmmakepkg command with the “–m tkit/vtn/vtn –n <vm name>“ options. The generated
package configuration file will need to be edited before running cmapplyconf.
• When using the cmdeployvpkg command with the –U option to unpackage a VM guest, it will result in the
modify, runnable, and visible status for the VM guest being disabled on all nodes except where the
command was run. You must manually re-enable those status parameters before you can run the VM guest on those
nodes.
• When performing a package conversion for a package created with the Integrity VM Serviceguard toolkit, using
the cmdeployvpkg command, it is important to understand that the conversion process does not preserve any user
customizations from the package being converted, such as external scripts or package services. Instead, it creates
a new package configuration file, using the same package and VM guest names as the original, with the SG-IVS
modules. Any user modifications from the original package must be added to the new package configuration file
before running cmapplyconf.
• In the version of SG-IVS available at the time of writing, when performing an online package conversion using the
cmdeployvpkg command, it is very important to understand how the process works. You must run
cmdeployvpkg with the –C option on the node where the VM guest package is currently running, and an online
migration is done to move the VM guest to a new node in the cluster and the existing package configuration is
deleted. You cannot specify which node the VM guest will be migrated to online. Once the VM guest has been
migrated and the package configuration has been deleted, the command tells you go to the node where the
unpackaged VM guest was migrated to, and run cmdeployvpkg without the –C option, and this will create the
new package configuration file. Once you have made any edits and applied the new package configuration, you
must run “cmrunpkg <package_name>“ on the node where the unpackaged VM guest is currently running. The
package will then discover that the VM guest is already running and will begin monitoring the VM guest and will
start any other package services if defined. However, you MUST NOT start the package using “cmmodpkg –e
<package_name>“, as that could start the package on a node other than where the unpackaged VM guest is
currently running, resulting in another instance of the VM guest being started and the potential to cause data loss or
data corruption on any storage used by the VM guest.
• You should not use the Integrity VM Serviceguard toolkit commands, hpvmsg_package and hpvmsg_move for
managing packages created with the SG-IVS toolkit.