The following figure illustrates an example configuration of the co-located topology.
Machine SYS0 hosts Enterprise Server instance A, machine SYS1 hosts Enterprise Server instance B, machine SYS2 hosts Enterprise Server instance C, and machine SYS3 hosts Enterprise Server instance D.
These four instances form a cluster that persists information to the two DRUs:
DRU0 comprises two machines, SYS0 and SYS2. HADB node active 0 is on the machine SYS0. HADB node spare 2 is on the machine SYS2.
DRU1 comprises two machines, SYS1 and SYS3. HADB node active 1 is on the machine SYS1. HADB node spare 3 is on the machine SYS3.