Re: Having a human to intervene
Were these 2 datacenters really 11k miles apart?
Latency usually covers round-trip time, and speed-of-light in fibre is only 2x10^8 m/s, so 60mS is more like 6000km of pure fibre separation. That is roughly the distance between US East & West coasts by fibre, but your point is still valid. It's too slow for synchronous replication, so you cannot guarantee that both sides are 100% in sync. Any failover solution has to take that into account.