HP P6000 Continuous Access Implementation Guide (T3680-96431, August 2012)

System fan-out replication
In the system fan-out replication shown in Figure 14 (page 47), one DR group is replicated from
array A to array B, and another DR group is replicated from array A to array C.
CAUTION: In a mixed array environment that includes an EVA3000/5000 array, the host ports
of the fan-in target or the fan-out source should be isolated. This is necessary because an
EVA3000/5000 has fewer resources to handle inter-array replication traffic. To accommodate
the reduced number of available resources on the EVA3000/5000, an EVAx100 or EVAx400
array limits its resource allocation to match the lower protocol of the EVA3000/5000. This may
result in reduced replication traffic performance between arrays normally capable of higher
performance.
This situation occurs if the same host port (shared port) is used to connect to both an EVA3000/5000
and an EVA4000/6000/8000, EVAx100, or EVAx400. (For information on displaying
array-to-array connection information, see “Changing host port data replication settings” (page 56).)
If the shared host port configuration is temporary, after the EVA3000/5000 is removed the shared
port must be disabled and then enabled, which forces the connection to the remaining arrays to
close and reopen. This ensures that the remaining arrays use the higher level of available resources
within the controller software. If the shared host port configuration is not temporary, the connections
must use isolated host ports for EVA3000/5000 data replication connections to eliminate the
possibility of reduced replication performance. For details on creating port isolation using zoning,
see “Dual-fabric replication zone fan-in/fan-out for port isolation: sheet 1” (page 91).
Figure 14 System fan-out replication
1. Array A
2. Array B
3. Array C
Planning replication relationships 47