Redis Sentinel: Command cannot be issued to a slave: ROLE

[dave-yotta]

Hey we've set up redis sentinel but connecting with stackexchange.redis getting a ROLE command sent to a slave inside GetSentinelMasterConnection.

I'm sure this is something we've messed up, it's been tricky to get set up - any chance of help? <3

ERROR Hangfire.Pro.Redis.RedisStorage [(null)] - Couldn't connect to Redis server(s) 'redis-sentinel-0.redis-sentinel-svc.gnigats.svc.cluster.local:26379,redis-sentinel-1.redis-sentinel-svc.gnigats.svc.cluster.local:26379,redis-sentinel-2.redis-sentinel-svc.gnigats.svc.cluster.local:26379', will reconnect in 00:00:30
StackExchange.Redis.RedisCommandException: Command cannot be issued to a slave: ROLE
   at StackExchange.Redis.ConnectionMultiplexer.TryPushMessageToBridge[T](Message message, ResultProcessor`1 processor, ResultBox`1 resultBox, ServerEndPoint& server) in C:\projects\stackexchange-redis\StackExchange.Redis\StackExchange\Redis\ConnectionMultiplexer.cs:line 1934
   at StackExchange.Redis.ConnectionMultiplexer.ExecuteSyncImpl[T](Message message, ResultProcessor`1 processor, ServerEndPoint server) in C:\projects\stackexchange-redis\StackExchange.Redis\StackExchange\Redis\ConnectionMultiplexer.cs:line 2196
   at StackExchange.Redis.RedisServer.Role(CommandFlags flags) in C:\projects\stackexchange-redis\StackExchange.Redis\StackExchange\Redis\RedisServer.cs:line 326
   at StackExchange.Redis.ConnectionMultiplexer.GetSentinelMasterConnection(ConfigurationOptions config, Action`1 log) in C:\projects\stackexchange-redis\StackExchange.Redis\StackExchange\Redis\ConnectionMultiplexer.Sentinel.cs:line 210
   at Hangfire.Pro.Redis.RedisStorage.CreateMultiplexer(EventWaitHandle reconnectEvent)
   at Hangfire.Pro.Redis.RedisStorage.ConnectLoop() in C:\projects\hangfire-pro-redis\src\Hangfire.Pro.Redis\RedisStorage.cs:line 508

[NickCraver]

What version of StackExchange.Redis are you using here? Based on terminology, we'd assume it's quite old - does this repro on latest?

[qmosselm]

Hi @dave-yotta, I got the same issue with Hangfire.Pro.Redis.
Were you able to find a solution ? It seems they are using the 1.2.7 build binaries of StackExchange.Redis in the last version of Hangfire.Pro.Redis.

[mgravell]

I suspect this will be indirectly fixed by #3088

[mgravell]

Addressed in StackExchange.Redis 2.13.17 (#3088): the sentinel primary-verification path now wraps server.Role() in try/catch with a !server.IsReplica fallback, so 'Command cannot be issued to a slave: ROLE' can no longer propagate from there. Closing as completed.

If you still hit this on a current build, please comment and we'll reopen (stale replica-state may still cause a retry delay).