Run Operation on specific Shards or SE.Redis able to redirect traffic to failed shards

[ribarua]

Hi,
We're using multiple Redis Caches with 10 shards, and occasionally due to Redis patching or Host OS updates, we see one or the other shard having issues. We were wondering if there's any way the StackExchange.Redis can understand this and redirect traffic to other shards, or allow the client (us) to be able to make connections to individual shards directly. Or any recommendation to overcome this scenario ?

[mgravell]

What sharding model are you using here? If this is "redis-cluster": we have to follow the cluster topology - we can't make our own decisions. If you're using something else: we don't know about it... so...

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On Wed, 19 Oct 2022, 21:53 ribarua, ***@***.***> wrote: Hi, We're using multiple Redis Caches with 10 shards, and occasionally due to Redis patching or Host OS updates, we see one or the other shard having issues. We were wondering if there's any way the StackExchange.Redis can understand this and redirect traffic to other shards, or allow the client (us) to be able to make connections to individual shards directly. Or any recommendation to overcome this scenario ? — Reply to this email directly, view it on GitHub <#2278>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAEHMGNDN5DQI7VV4TNBLTWEBNS3ANCNFSM6AAAAAARJP73VE> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[philon-msft]

It sounds like this is an Azure Cache for Redis, meaning redis-cluster topology. The latest versions of StackExchange.Redis do a pretty great job of managing topology and restoring connections after server maintenance.
One important note: with redis-cluster, the data set is distributed across shards, not duplicated across shards, so requests can't be redirected to another shard because it won't contain the needed data. Instead, it's recommended to update to maximize connection resilience by upgrading to the latest version of StackExchange.Redis and following guidance here: https://learn.microsoft.com/azure/azure-cache-for-redis/cache-best-practices-connection

[NickCraver]

This should be helped by #2286