问题
I am running master-slave redis with sentinel, when I kill my master, the lowest priority slave becomes the new master.
But when I start my old master again, which has an even lower priority, it does not become the master.
Is this behavior intended and somewhere documented? I don't seem to find anything in the redis sentinel documentation.
回答1:
In regards to "failover behavior. It's clearly states that the lowest priority slave is preferred (unless it's zero) - see the docs ("Slaves priority" section)
In Regards to "fallback" behavior. Once the old master goes back online, it will not regain it's old master status back. This is intentional as the idea is to change the state of the sentinel ha-cluster as little as possible. Once the next failover takes place, if the old master ( now a slave ) has the lowest priority, it'll promoted to master again.
来源：https://stackoverflow.com/questions/43351045/is-master-always-redis-instance-with-smallest-priority