What happened: Had an outage in US North Virginia 1 region for about 6 minute (12/17 03:47am PST - 03:53am PST), during maintenance for infrastructure scale-in (Redis change).
Possible cause: Tried to perform an internal maintenance, but a relevant script didn’t work properly and it made huge heavy queries and traffic surge.
Instant Measure: Rollbacked the Redis cluster changes, system backs to normal.
Customer Impact: Customers in the US North Virginia 1 region may have experienced chat service failures during that time.