Managing Serviceguard Eighteenth Edition, September 2010

In addition, relocatable addresses (but not stationary addresses) can be taken over by
an adoptive node on the same subnet if control of the package is transferred. This means
that applications can access the package via its relocatable address without knowing
which node the package currently resides on.
IMPORTANT: Any subnet that is used by a package for relocatable addresses should
be configured into the cluster via NETWORK_INTERFACE and either STATIONARY_IP
or HEARTBEAT_IP in the cluster configuration file. For more information about those
parameters, see “Cluster Configuration Parameters ” (page 143). For more information
about configuring relocatable addresses, see the descriptions of the package ip_
parameters (page 298).
NOTE: It is possible to configure a cluster that spans subnets joined by a router, with
some nodes using one subnet and some another. This is called a cross-subnet
configuration. In this context, you can configure packages to fail over from a node on
one subnet to a node on another, and you will need to configure a relocatable address
for each subnet the package is configured to start on; see “About Cross-Subnet Failover”
(page 201), and in particular the subsection “Implications for Application Deployment”
(page 202).
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. You can define heartbeat IPs,
stationary IPs, and relocatable (package) IPs as IPv4 or IPv6 addresses (or certain
combinations of both).
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).
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