SET errors on Azure Redis cluster

[MatanShabtay]

We have a Redis cluster on Azure (Premium P4 Redis size).
We've noticed that we're seeing a lot of SET / SETX failures specifcally on this Redis instance.

The error we see is [ partial details from the exception thrown]:
StackExchange.Redis.RedisConnectionException: Command cannot be issued to a slave: SET

at StackExchange.Redis.PhysicalBridge.WriteMessageToServerInsideWriteLock(PhysicalConnection connection, Message message) in C:\projects\stackexchange-redis\src\StackExchange.Redis\PhysicalBridge.cs:line 1221

Note that our application communicates with another Redis server on Azure that is not Redis cluster and we dont see these errors at all.

Any suggestions?
As a workaround, I thought about calling IDatabase.StringSetAsync with CommandFlag.MasterOnly

What do you think ?

[SarapinIT]

Hello, @MatanShabtay. On which version of the library do you have this problem? I tried to reproduce and I got it for the old version 1.0.245

[NickCraver]

This is ultimately due to some reconnect issues after a redis failover behind the scenes in Azure. Folding this into #1120 which has another fix on the way in #1374 to resolve this scenario. The failover can trigger a stuck bad state on active pipes in our client that's been identified and is being resolved.

[yuzhangyi]

Hi, @NickCraver, could you help give some suggestion on following issue we meet in Redis? The version we used is StackExchange.Redis.2.0.601, thanks!

Failed to operate data with Redis Cache while error is: DeleteValueAsyncInternal failed with key E940E38E-269B-4430-8891-D868F21170DB@EXTERNALACTIVITY, field 1456D447-5749-4EF8-A190-106E27F35665@1456D447-5749-4EF8-A190-106E27F35665 and exception StackExchange.Redis.RedisConnectionException: InternalFailure on HDEL E940E38E-269B-4430-8891-D868F21170DB@EXTERNALACTIVITY ---> StackExchange.Redis.RedisCommandException: Command cannot be issued to a slave: HDEL E940E38E-269B-4430-8891-D868F21170DB@EXTERNALACTIVITY
at StackExchange.Redis.PhysicalBridge.WriteMessageToServerInsideWriteLock(PhysicalConnection connection, Message message)
--- End of inner exception stack trace ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.DataTransfer.Common.AzureRedisDataManagement.RedisKeyValueCache.d__15.MoveNext()
InternalFailure on HDEL E940E38E-269B-4430-8891-D868F21170DB@EXTERNALACTIVITY.