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

For more information, rules, and instructions see “Maintaining a Package” in Chapter
7 of the latest version of Managing Serviceguard, which you can find at the address given
under “Documents for This Version ” (page 37).
VLAN Configurations
Serviceguard for Linux A.11.19, with the patches listed under “July 2009 Patches”
(page 9), provides support for Virtual LAN configuration (VLAN). VLAN allows
logical grouping of network nodes, regardless of their physical locations. You can use
VLAN interfaces for both heartbeat and data networks.
Configuration Restrictions
Linux allows up to 1024 VLANs to be created from a physical NIC port. A large pool
of system resources is required to accommodate such a configuration; Serviceguard
could suffer performance degradation if many network interfaces are configured in
each cluster node. To prevent this and other problems, Serviceguard imposes the
following restrictions:
• A maximum of 30 network interfaces per node is supported. The interfaces can be
physical NIC ports, VLAN interfaces, Channel Bonds, or any combination of these.
• Only port-based and IP-subnet-based VLANs are supported. Protocol-based VLAN
is not supported because Serviceguard does not support any transport protocols
other than TCP/IP.
• Each VLAN interface must be assigned an IP address in a unique subnet.
• Using VLAN in a Wide Area Network cluster is not supported.
Additional Heartbeat Requirements
VLAN technology allows great flexibility in network configuration. To maintain
Serviceguard’s reliability and availability in such an environment, the heartbeat rules
are tightened as follows when the cluster is using VLANs:
1. VLAN heartbeat networks must be configured on separate physical NICs or
Channel Bonds, to avoid single points of failure.
2. Heartbeats are still recommended on all cluster networks, including VLANs.
3. If you are using VLANs, but decide not to use VLANs for heartbeat networks,
heartbeats are recommended for all other physical networks or Channel Bonds
specified in the cluster configuration file.
New Kinds of Package Dependency
As of Serviceguard A.11.18, you can make a package dependent on any other package
or packages running on the same cluster node, subject to the restrictions spelled out in
Chapter 6 of Managing Serviceguard for Linux.
Serviceguard A.11.19 adds two new capabilities: you can specify broadly where the
package depended on must be running, and you can specify that it must be down.
20 Serviceguard for Linux Version A.11.19 Release Notes