How do I respond to redundancy failures?

Overview

The following describe the NFM-P actions in response to various types of redundancy failures.

Collocated system, primary station unreachable
Figure 17-11: Primary server and database station down, collocated system
Primary server and database station down, collocated system

The following occur when the primary station becomes unresponsive:

Distributed system, primary server unreachable
Figure 17-12: Primary server unreachable, distributed system
Primary server unreachable, distributed system

The following occur when the primary station becomes unresponsive:

Distributed system, standby server unreachable
Figure 17-13: Standby server unreachable, distributed system
Standby server unreachable, distributed system

The following occur when the standby station becomes unresponsive:

Distributed system, managed network unreachable by primary side
Figure 17-14: Network failure on primary side, distributed system
Network failure on primary side, distributed system

The following occur after the connectivity loss is detected:

Note: You can eliminate a single point of hardware or network failure by using redundant interfaces and redundant physical network paths. See the NSP NFM-P Planning Guide for more information.

Split complex

A split complex is a scenario in which both servers in a collocated or distributed system lose contact, but each server can communicate with the preferred database, as shown in the following figure.

Figure 17-15: Split complex, collocated or distributed system
Split complex, collocated or distributed system

The following occur after the connectivity loss is detected: