Managing Serviceguard Nineteenth Edition, Reprinted June 2011

Figure 26 Cluster After Local Network Switching
As the standby interface takes over, IP addresses will be switched to the hardware path associated
with the standby interface. The switch is transparent at the TCP/IP level. All applications continue
to run on their original nodes. During this time, IP traffic on Node 1 will be delayed as the transfer
occurs. However, the TCP/IP connections will continue to be maintained and applications will
continue to run. Control of the packages on Node 1 is not affected.
NOTE: On Ethernet networks, Serviceguard supports local failover between network interfaces
configured with “Ethernet protocol” or between network interfaces configured with “SNAP
encapsulation within IEEE 802.3 protocol.” You cannot use both protocols on the same interface,
nor can you have a local failover between interfaces that are using different protocols.
Another example of local switching is shown in Figure 27. In this case a failure affecting segment
2 causes both nodes to switch to the LAN cards attached to segment 1.
Figure 27 Local Switching After Cable Failure
68 Understanding Serviceguard Software Components