How to use Redis(master-salve) as Web Cache?

Nowadays,Most Application use Redis as cache Service to improve user experience, now I will introduce how to use Redis(master-slave-sentinel) as web cache.

Firstly,
I'd like to introduce the application how to use the Redis(master-slave-sentinel), App will talk with Redis Sentinel and master/slave transient to application, so when have Redis master switch to slave, Application still work well,below is detail Sequence diagram.

Secondly,
I'd like to introduce how to give one good Redis design to support business extends, I involved one concept "redis pool", that's includes "master-slave-sentinel", it maybe 1:1:3 or 1:2:3, so one pool can support one data centers all business or have several pools to service one data center business; anther is to ensure cache more simple, don't do data center redis pool replication, below is detail logic deployment Architecture.

Thirdly,
I'd like to introduce how to monitor the Redis health state, now we use python plug-in on collect to monitor the redis, below is detail work flow.