Managing HP Serviceguard for Linux, Eighth Edition, March 2008

Understanding Serviceguard Software Components
How the Network Manager Works
Chapter 376
Types of IP Addresses
Both IPv4 and IPv6 address types are supported in Serviceguard. IPv4
addresses are the traditional addresses of the form n.n.n.n where n is a
decimal digit between 0 and 255. IPv6 addresses have the form
x:x:x:x:x:x:x:x where x is the hexadecimal value of each of eight
16-bit pieces of the 128-bit address. Only IPv4 addresses are supported
as heartbeat addresses, but both IPv4 and IPv6 addresses (including
various combinations) can be defined as stationary IPs in a cluster. Both
IPv4 and IPv6 addresses also can be used as relocatable (package) IP
addresses.
Adding and Deleting Relocatable IP Addresses
When a package is started, a relocatable IP address can be added to a
specified IP subnet. When the package is stopped, the relocatable IP
address is deleted from the specified subnet. These functions are
performed by the cmmodnet command in the package master control
script (package control script for legacy packages).
IP addresses are configured only on each primary network interface
card. Multiple IP addresses on the same network card must belong to the
same IP subnet.
Load Sharing
Serviceguard allows you to configure several services into a single
package, sharing a single IP address; in that case all those services will
fail over when the package does. If you want to be able to load-balance
services (that is, move a specific service to a less loaded system when
necessary) you can do so by putting each service in its own package and
giving it a unique IP address.