There are specific intersite link requirements that must
be met when planning to use IP partnership for remote copy.
If you use IP partnership, you must meet the following requirements:
- TCP ports 3260 and 3265 are used by systems for IP
partnership communications; therefore these ports will need to be
open.
- The maximum supported round-trip time between systems
is 80 milliseconds (ms) for a one Gbps link.
- The maximum supported round-trip time between systems
is 10 milliseconds (ms) for a 10 Gbps link.
- For IP partnerships, the recommended method of copying is Global
Mirror with change volumes.
This method is recommended because
of the performance benefits. Also, Global Mirror and Metro Mirror
might be more susceptible to the loss of synchronization.
- The amount of intersite heartbeat traffic is one
megabit per second (Mbps) per link.
- The minimum bandwidth requirement for the intersite
link is 10 Mbps. This, however, scales up with the amount of host
I/O that you choose to do. Figure 1 describes the scaling of host I/O.
Figure 1. Scaling of host I/O
The equation that can describe the approximate
minimum bandwidth required between two systems with <5 ms round-trip
time and errorless link follows:
Minimum
intersite link bandwidth in Mbps > Required Background Copy in Mbps
+ Maximum Host I/O in Mbps + 0.125 Mbps heartbeat traffic
Increasing latency and errors will result
in a higher requirement for minimum bandwidth.