Managing HP Serviceguard for Linux, Sixth Edition, August 2006

Understanding Serviceguard Software Components
How the Package Manager Works
Chapter 3 47
A package switch involves moving packages and their associated IP
addresses to a new system. The new system must already have the same
subnetwork configured and working properly, otherwise the packages
will not be started. With package failovers, TCP connections are lost.
TCP applications must reconnect to regain connectivity; this is not
handled automatically. Note that if the package is dependent on multiple
subnetworks, all subnetworks must be available on the target node
before the package will be started.
The switching of relocatable IP addresses is shown in Figure 3-6 and
Figure 3-7. Figure 3-6 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 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 3-6 Before Package Switching