Why "Hot" Matters

Three multi-region strategies:

Cold : Backup region is off. You start it when primary fails. RTO: hours.

Warm : Backup region runs on minimum capacity. Scale up on failover. RTO: 15-30 minutes.

Hot : Both regions serve live traffic simultaneously. RTO: seconds.

If you need under 15 minutes RTO, you need hot. Everything else is marketing copy.

The Illusion of Warm Failover

Warm sounds great on paper. In practice, on the day you need it:

The warm region has never seen real load

DNS cache propagation takes 5-15 minutes

Autoscaling lags because it's starting cold

Your team has never run on the warm region

Half your connection strings are hardcoded to the primary

Warm failover works in tabletop exercises. It does not work during real incidents under pressure.…