HP Serviceguard for Linux Version A.11.19 Release Notes, October 2009

Recommendation for IPv6-Only Mode
If you decide to migrate the cluster to IPv6-only mode, you should plan to do so while
the cluster is down.
Rules and Restrictions for Mixed Mode
• Red Hat 5 clusters are not supported.
NOTE: This also applies if HOSTNAME_ADDRESS_FAMILY is set to IPv6; Red
Hat 5 supports only IPv4-only clusters.
• The hostname resolution file on each node (for example, /etc/hosts) must
contain entries for all the IPv4 and IPv6 addresses used throughout the cluster,
including all STATIONARY_IP and HEARTBEAT_IP addresses as well any private
addresses. There must be at least one IPv4 address in this file (in the case of /etc/
hosts, the IPv4 loopback address cannot be removed).
In addition, the file must contain the following entry:
::1 localhost ipv6-localhost ipv6-loopback
For more information and recommendations about hostname resolution, see
“Configuring Name Resolution” in Chapter 5 of Managing Serviceguard.
• You must use $SGCONF/cmclnodelist, not ~/.rhosts or /etc/hosts.equiv,
to provide root access to an unconfigured node.
See “Allowing Root Access to an Unconfigured Node” in Chapter 5 of Managing
Serviceguard for more information.
• 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.
This also applies if HOSTNAME_ADDRESS_FAMILY is set to IPV6. See “About
Cross-Subnet Configurations” (page 29) for more information.
• Virtual Machines are not supported.
You cannot configure a virtual machine as either a node or a package if
HOSTNAME_ADDRESS_FAMILY is set to ANY or IPV6.
Restrictions if You Have Not Applied the July 2009 Patch
A.11.19 without the patch supports only IPv4–only and mixed-mode clusters; you
cannot configure an IPv6–only cluster.
18 Serviceguard for Linux Version A.11.19 Release Notes