[3.0.x] Known Behavior Change (Admin Command), but cannot trace back reason

[tebeco]

Hello,

As per #3119 and https://github.com/tebeco/TeBeCo.SE.Redis.Telemetry

I'm noticed internal changes from SE.Redis have caused Datadog extensions to crash.
Their Support indicated that updated their extensions would update transitivly their own Tracers.
I just updated the Extensions to what is 3.48 (they hinted at 3.46)

Telemetry is back ... with a Twist:

We can now notice a call to CLIENT:

RedisCommandException: This operation is not available unless admin mode is enabled: CLIENT

3.0.x does indicate that it will now respect Admin mode

StackExchange.Redis.RedisCommandException: This operation is not available unless admin mode is enabled: CLIENT
   at StackExchange.Redis.ConnectionMultiplexer.CheckMessage(Message message) in /_/src/StackExchange.Redis/ConnectionMultiplexer.cs:line 345
   at StackExchange.Redis.RedisBase.ExecuteSync[T](Message message, ResultProcessor`1 processor, ServerEndPoint server, T defaultValue) in /_/src/StackExchange.Redis/RedisBase.cs:line 62
   at StackExchange.Redis.RedisServer.ExecuteSync[T](Message message, ResultProcessor`1 processor, ServerEndPoint server, T defaultValue) in /_/src/StackExchange.Redis/RedisServer.cs:line 714
   at StackExchange.Redis.RedisServer.Execute(String command, ICollection`1 args, CommandFlags flags) in /_/src/StackExchange.Redis/RedisServer.cs:line 1044
   at StackExchange.Redis.ConnectionMultiplexer.AddLibraryNameSuffix(String suffix) in /_/src/StackExchange.Redis/ConnectionMultiplexer.LibraryName.cs:line 45

It is unclear (my knownledge is very limited) if I did the setup wrong from the code.
What i mean is that, is it normal for the app to emit a CLIENT command.
It's targetting a Azure Cache for Redis (not yes Azure Redis Managed)

It's also unclear how would i approach fixing it and/or what's the impact since we see that the rest of the app seems to behave

[tebeco]

To clarify, adding this seems to make the error goes away as it's the expected "technical behavior"
I'm curious if it's my C# code setup internally causing a CLIENT call or Datadog extensions

        builder
            .Services
            .AddSingleton<IConnectionMultiplexer>(sp =>
            {
                var distributedCacheOptions = sp.GetRequiredService<IOptions<DistributedCacheOptions>>().Value;

                var configurationOptions = ConfigurationOptions.Parse(distributedCacheOptions.ConnectionString);
                configurationOptions.LoggerFactory = sp.GetRequiredService<ILoggerFactory>();

                // AbortOnConnectFail : (Recommended to set to false by Azure docs and others)
                // When set to true, the connection can't reconnect after a network failure.
                // Set to false and let StackExchange.Redis reconnect automatically.
                configurationOptions.AbortOnConnectFail = false;

+               // Will allow admin commands such as "FLUSH" or "CLIENT"
+               // It is unclear what is currently calling "CLIENT" in UAT but error has been spotted when updating to 3.x
+               configurationOptions.AllowAdmin = true;

                return ConnectionMultiplexer.Connect(configurationOptions);
            });

[mgravell]

I'm guessing the CLIENT command is being issued via Execute[Async] - see the 3.0 release note: https://github.com/StackExchange/StackExchange.Redis/releases/tag/3.0.0

Basically, CLIENT has some really powerful subcommands (kill, pause) - and others that will do weird things to the connection until it has first part support (caching, etc).

Historically Execute wasn't great at spotting this. Now it is, but client was always an admin command for this reason. If there is a necessary and reasonable command: we can add first party support fairly easily.

[mgravell]

Ooh, is that coming from inside SE.Redis itself? If so: I'll whitelist that ASAP. That's an error by me: we know this usage is OK.

[mgravell]

Yeah, sorry this is me. 3.0 is still new - will look in the morning.

[mgravell]

Cause:

StackExchange.Redis/src/StackExchange.Redis/ConnectionMultiplexer.LibraryName.cs

Line 45 in 0b03ed1

server.Execute("CLIENT", args, CommandFlags.FireAndForget);

Totally me

[tebeco]

do you want me to close this issue if you opened another one ?

i don't mind having one or both tbh
not sure what's best for visibility in case someone have exactly the same error and find this one

for now i've set AllowAdmin since we're probably going to need to use Flush anyway but that's unrelated