21 May 2026
Cutover rehearsal without theatre
Rehearsals fail when they become presentations. People read runbooks aloud while nobody touches DNS, feature flags, or the actual monitoring queries that will decide success.
A useful rehearsal picks one thin path through production-like systems: a non-critical hostname, a canary cohort, or a reporting database with a known restore point. Practise the communication cadence too — who posts, who decides abort, who informs support.
Time the soak. If your plan claims thirty minutes to confidence, the rehearsal should show whether that number is honest. Adjust the plan; do not adjust the stopwatch story after a real outage.
Document the embarrassing findings. The DNS TTL mistake, the forgotten license check, the pager that still points at a departed engineer — those are the reasons you rehearse. Migration advisory packs that omit rehearsal notes are unfinished.