Spinnaker is Down with the Error of "OOM command not allowed when used memory > 'maxmemory" (Redis)

Issue

The Spinnaker environment is down and unaccessible, and comes with the Redis error as following: {"timestamp":1601481892xxx,"status":500,"error":"Internal Server Error","message":"OOM command not allowed when used memory > 'maxmemory'.; nested exception is redis.clients.jedis.exceptions.JedisDataException: OOM command not allowed when used memory > 'maxmemory'."}

Cause

The OOM command not allowed when used memory > ‘maxmemory’ error means that Redis was configured with a memory limit and that particular limit was reached.In other words: its memory is full, it can’t store any new data.