Figure 9.2 Example For N:1 Standby - Fujitsu PRIMEQUEST 480 System Design Manual

N:1 standby
One standby node is prepared for multiple active nodes. Since only one standby node
is required for multiple active nodes, a cluster system with good cost-performance can
be constructed.
Active A
Node A
Mutual standby
Each active node also operates as a standby node for another node. If an error occurs
in one node, the other node takes over job processing. During normal operation, all
node can be used, but when a malfunction occurs, the job processing for two nodes
needs to be performed on a single node. Therefore, the node needs to be constructed
in such a way that a single node can perform the processing for the jobs on both
nodes.
Active A
Standby B
C122-B001-02EN
Standby A
Active B
Standby B
Node B

Figure 9.2 Example for N:1 standby

Standby A
Active B
Node A Node B
Figure 9.3 Example for mutual standby
When
node A is
Node C
faulty
When
node A is
faulty
9.1 The basics of clustering
Error Error
Active B
Node A Node B
Active A
Error Error
Active B
Node A Node B
Standby A
Standby B
Node C
9-3