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Blue-Green Cutover Simulator

Warm green, switch the traffic control point, drain blue, and see how shared-state compatibility decides whether rollback is real.

Cutover planeChoose where the live pointer changes
Shared stateChoose whether blue and green stay compatible during rollback
UsersAthens, Milan, DublinHTTPS sessionsTraffic switchL7 gatewayL7 gateway points at blueNo cutover yetbluerelease 2026.06.06100% live trafficready and steady1,420 open client sessionsscheduler lease ownerschema v41Blue is the current truth source for user traffic.greenrelease 2026.06.130% user trafficboot image only0 client sessionsworkers disabledschema v41 candidateGreen exists, but it has not earned admission yet.current admission path
Cutover control
L7 gateway points at blue
Green is deployed but not eligible for user traffic.
Rollback window
No cutover yet
Before promotion, blue owns HTTP traffic, worker leases, and operational trust. Green should look production-capable without yet being production-live.
State risk
Additive shared-state change
The dangerous shortcut here is calling green ready just because the process started.
Step 1 / 6Blue owns production while green is still parked

Blue is live. Green exists, but it is not serving users yet. At this point, blue-green is only a promise unless the standby environment can really take production traffic.

Before promotion, blue owns HTTP traffic, worker leases, and operational trust. Green should look production-capable without yet being production-live.

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