HP Serviceguard manual What Is Mixed Mode?, IPV6 or ANY, Recommendations for IPv6-Only Mode

•The node's public LAN address (by which it is known to the outside world) must be the last address listed in /etc/hosts.

Otherwise there is a possibility of the address being used even when it is not configured into the cluster.

•You must use $SGCONF/cmclnodelist, not ~/.rhosts or /etc/hosts.equiv, to provide root access to an unconfigured node.

NOTE: This also applies if HOSTNAME_ADDRESS_FAMILY is set to ANY. See “Allowing Root Access to an Unconfigured Node” (page 166) for more information.

•If you use a Quorum Server, you must make sure that the Quorum Server hostname (and the alternate Quorum Server address specified by QS_ADDR, if any) resolve to IPv6 addresses, and you must use Quorum Server version A.04.00 or later. See the latest Quorum Server release notes for more information; you can find them at http://www.hp.com/go/ hpux-serviceguard-docs under HP Serviceguard Quorum Server Software.

NOTE: The Quorum Server itself can be an IPv6–only system; in that case it can serve IPv6–only and mixed-mode clusters, but not IPv4–only clusters.

•If you use a Quorum Server, and the Quorum Server is on a different subnet from cluster, you must use an IPv6-capable router.

•Hostname aliases are not supported for IPv6 addresses, because of operating system limitations.

NOTE: This applies to all IPv6 addresses, whether HOSTNAME_ADDRESS_FAMILY is set to

IPV6 or ANY.

•Cross-subnet configurations are not supported in IPv6-only mode.

NOTE: This also applies if HOSTNAME_ADDRESS_FAMILY is set to ANY. See “Cross-Subnet Configurations” (page 30) for more information about such configurations.

•VxVM, VxFS, and CVM/CFS are supported in IPv6–only mode on HP Serviceguard A.11.20 April 2011 patches with Veritas Storage Foundation™ 5.1 SP1 and later.

NOTE: CVM/CFS can be installed on any system in an IPv6–only cluster using HP Serviceguard A.11.20 April 2011 patches with Veritas Storage Foundation™ 5.1 SP1 and later, even if they are not configured.

This also means that the Serviceguard component of bundles that include Serviceguard cannot be configured in IPV6 mode prior to Veritas Storage Foundation™ 5.1 SP1.

•HPVM is not supported IPv6-only mode. You cannot configure a virtual machine either as a node or a package in an IPv6-only cluster.

Recommendations for IPv6-Only Mode

IMPORTANT: Check the current Serviceguard release notes for the latest instructions and recommendations.

•If you decide to migrate the cluster to IPv6-only mode, you should plan to do so while the cluster is down.

What Is Mixed Mode?

If you configure mixed mode (HOSTNAME_ADDRESS_FAMILY set to ANY), then the addresses used by the cluster, including the heartbeat, and Quorum Server addresses if any, can be IPv4 or

108 Planning and Documenting an HA Cluster