"@cscotta Hi, you misunderstood how it works: Pub/Sub is only used for discovery on startup. Sentinel-to-sentinel p2p for critical stuff."

Pub/Sub is used to make the configuration simpler when you start a Sentinel cluster at a cold time when everything is working and your master is ok.

This allows us to auto-discover the other Sentinels, to check the slaves, and so forth.

Instead in order to understand if a system is down, who is the Sentinel that performs the failover, and for all the critical stuff, Sentinel to Sentinel messages are used without caring if the master Pub/Sub works.