Managing Serviceguard Fifteenth Edition, reprinted May 2008

Understanding Serviceguard Software Components
How the Package Manager Works
Chapter 3 77
started. (In a cross-subnet configuration, all the monitored subnets that
are specified for this package, and configured on the target node, must be
up.)
If the package has a dependency on a resource or another package, the
dependency must be met on the target node before the package can start.
The switching of relocatable IP addresses on a single subnet is shown in
Figure 3-5 and Figure 3-6. Figure 3-5 shows a two node cluster in its
original state with Package 1 running on Node 1 and Package 2 running
on Node 2. Users connect to the node with the IP address of the package
they wish to use. Each node has a stationary IP address associated with
it, and each package has an IP address associated with it.
Figure 3-5 Before Package Switching
Figure 3-6 shows the condition where Node 1 has failed and Package 1
has been transferred to Node 2 on the same subnet. Package 1’s IP
address was transferred to Node 2 along with the package. Package 1
continues to be available and is now running on Node 2. Also note that
Node 2 can now access both Package1’s disk and Package2’s disk.