Link Bandwidth and Latency
To configure high-availability (HA), you must consider the bandwidth and latency between the primary and secondary HA hosts.
If your HA cluster is using disk synchronization, the following conditions must be met:
The connection between the primary and secondary HA host has a minimum bandwidth of 1 gigabits per second (Gbps).
The latency between the primary and secondary HA host is less than 2 milliseconds (ms).
If your HA solution uses a wide area network (WAN) to geographically distribute the hosts in your cluster, latency increases with distance. If latency rises above 2 ms, then system performance is affected.