Redis PUB/SUB and high availability -

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currently i'm working on distributed test execution , reporting system. i'm planning use redis pub/sub message queue , message distribution system.

i'm new redis, i'm trying read many docs can , play around it. 1 of important topics high availability. said, i'm not expert, i'm aware of possible options - using sentinel, replication, clustering, etc.

what's not clear me how pub/sub feature , ha options related each other. what's best practice build reliable messaging system redis? reliable mean if redis message broker down there should kind of backup node (a slave?) should able take on role.

is there purely server-side solution? or need create smart wrapper around redis client handle this? sentinel-driven setup me?

doing pub sub in redis failover means thinking additional factors in client side. key piece understand subscriptions per-connection. if subscribed channel on node , fails, need handle reconnect , resubscribe. because subscriptions done @ connection level not can replicated.

regarding details how works , can expect see, along ways around see post made earlier year @ https://objectrocket.com/blog/how-to/reliable-pubsub-and-blocking-commands-during-redis-failovers

you can lower risk surface subscribing slaves , publishing master, need have non-promotable slaves subscribe , still need handle losing slave - there chance lose given slave there master.


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