Sockets error on Producer code .NET

[adammckay]

Describe the bug

An exception of type 'System.Net.Sockets.SocketException' occurred in System.Private.CoreLib.dll but was not handled in user code: 'No connection could be made because the target machine actively refused it.'

This is the send.cs file:
rabbitmq-tutorials/dotnet-stream/Send/Send.cs

This is the line where the error occurs (line 12):
var producer = await Producer.Create(new ProducerConfig(streamSystem, "hello-stream"));

Obviously, the first suspicion is that the endpoint or user/pass is set wrong. However, I have confirmed that they are set correctly and in line 7, my stream is indeed being created correctly. So that tells me that the host / port / user / pass are all set just fine.

await streamSystem.CreateStream(new StreamSpec("hello-stream")

I have checked other things like .net fw set to 8.0, latest client, streams plugin enabled, etc.

Reproduction steps

...

Expected behavior

I would expect the example code to just cruise along to finish and create a message.

Additional context

No response

[lukebakken]

Hi, thanks for using RabbitMQ and streams.

No connection could be made because the target machine actively refused it.

That error means one of these things:

• RabbitMQ is not running on the host to which you're trying to connect.
• There is a firewall blocking connections.
• RabbitMQ is not listening on the port you expect.

When you start RabbitMQ, ensure the following is logged to the console / file:

2025-09-08 09:04:17.197000-07:00 [info] <0.716.0> started Stream TCP listener on [::]:5552
2025-09-08 09:04:17.199000-07:00 [info] <0.734.0> started Stream TCP listener on 0.0.0.0:5552
...
...
...
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0> Server startup complete; 9 plugins started.
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_mqtt
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_top
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_stream_management
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_management
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_stream
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_prometheus
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_management_agent
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_web_dispatch
2025-09-08 09:04:17.720000-07:00 [info] <0.612.0>  * rabbitmq_amqp1_0
2025-09-08 09:04:17.779000-07:00 [info] <0.10.0> Time to start RabbitMQ: 8326 ms

On my Win 11 laptop, after starting RabbitMQ with the appropriate plugins, Send.cs runs correctly:

C:\Users\lrbakken\development\rabbitmq\rabbitmq-tutorials\dotnet-stream\Send [main ≡]
> dotnet run
 [x] Sent 'Hello, World'
 [x] Press any key to exit

[lukebakken]

I use the following PowerShell functions to start and stop RabbitMQ. I have RabbitMQ and Erlang installed via Scoop. Note that I started RabbitMQ with and without the -rabbitmq_stream advertised_host localhost setting and Send.cs ran correctly in both instances.

PS functions

Function Run-RabbitMQ {
    Param(
        [string]$NodeName='rabbit',
        [int]$NodePort=5672,
        [string]$Config="$HOME\development\lukebakken\rabbitmq\conf\rabbitmq.conf",
        [string]$AdvancedConfig=$null,
        [string]$ServerAdditionalErlArgs='+Muatags true -rabbitmq_stream advertised_host localhost',
        [switch]$Debug=$false,
        [switch]$Clean
    )

    if ($Clean) {
        Stop-Process -ErrorAction SilentlyContinue -Verbose -Name epmd
        Remove-Item -ErrorAction SilentlyContinue -Verbose -Recurse -Force "$env:AppData\RabbitMQ"
    }

    try
    {
        $env:RABBITMQ_ALLOW_INPUT = 'true'
        $env:RABBITMQ_CONFIG_FILE = $Config
        $env:RABBITMQ_NODENAME = $NodeName
        $env:RABBITMQ_NODE_PORT = $NodePort
        $env:RABBITMQ_SERVER_ADDITIONAL_ERL_ARGS = $ServerAdditionalErlArgs
        if (Test-Path -Path $AdvancedConfig) {
            $env:RABBITMQ_ADVANCED_CONFIG_FILE = $AdvancedConfig
        }
        if ($Debug) {
            $env:LOG = 'debug'
        }
        Write-Host 'ERLANG_HOME:'
        Write-Host $env:ERLANG_HOME
        Write-Host 'PATH:'
        Write-Host $env:PATH
        Write-Host 'RABBITMQ_* env variables:'
        Get-ChildItem -ErrorAction SilentlyContinue env:\LOG
        Get-ChildItem env:\RABBITMQ*
        $rmq_dir = Join-Path -Path $env:APPDATA -ChildPath RabbitMQ
        New-Item -ErrorAction SilentlyContinue -Type Directory -Path $rmq_dir
        Set-Content -LiteralPath (Join-Path -Path $rmq_dir -ChildPath enabled_plugins) -Encoding ascii -Value '[rabbitmq_management,rabbitmq_top,rabbitmq_stream,rabbitmq_stream_management,rabbitmq_prometheus,rabbitmq_mqtt,rabbitmq_amqp1_0].'
        & "$env:RABBITMQ_SERVER\sbin\rabbitmq-server.bat"
    }
    finally
    {
        Remove-Item -ErrorAction SilentlyContinue -Path env:\RABBITMQ_ALLOW_INPUT
        Remove-Item -ErrorAction SilentlyContinue -Path env:\RABBITMQ_CONFIG_FILE
        Remove-Item -ErrorAction SilentlyContinue -Path env:\RABBITMQ_NODENAME
        Remove-Item -ErrorAction SilentlyContinue -Path env:\RABBITMQ_NODE_PORT
        Remove-Item -ErrorAction SilentlyContinue -Path env:\RABBITMQ_SERVER_ADDITIONAL_ERL_ARGS
        Remove-Item -ErrorAction SilentlyContinue -Path env:\RABBITMQ_ADVANCED_CONFIG_FILE
        Remove-Item -ErrorAction SilentlyContinue -Path env:\LOG
    }
}

Function Stop-RabbitMQ {
    Param(
        [string]$NodeName='rabbit'
    )

    try
    {
        Remove-Item -ErrorAction SilentlyContinue -Verbose env:\LOG
        Remove-Item -ErrorAction SilentlyContinue -Verbose env:\RABBITMQ_ALLOW_INPUT
        Remove-Item -ErrorAction SilentlyContinue -Verbose env:\RABBITMQ_CONFIG_FILE
        Remove-Item -ErrorAction SilentlyContinue -Verbose env:\RABBITMQ_NODE*
        Remove-Item -ErrorAction SilentlyContinue -Verbose env:\RABBITMQ_SERVER_ADDITIONAL_ERL_ARGS
        & "$env:RABBITMQ_SERVER\sbin\rabbitmqctl.bat" -n $NodeName shutdown
    }
    finally
    {
        Write-Host "[INFO] RabbitMQ node '$NodeName' is shut down!"
    }
}

[michaelklishin]

To clarify why the above setting can be important specifically for streams: Stream Client Connections.

[michaelklishin]

@adammckay a one line problem description is not enough, we do not guess in this community.

No connection could be made because the target machine actively refused it

is Windows speak for "target host does not have a TCP socket bound to the said port", which means
that either the RabbitMQ node is not running at all, or a specific plugin is not enabled, or the port was overridden, or a firewall prevents the client from connecting.

See Troubleshooting Networking.

[adammckay]

Thanks for the PS Scripts. Michael - in my defense, I didn't give you one line or ask you to guess. I gave you your own code from github and told you what line errors. I then explained how it is NOT the configuration or ports or else the previous line of code would not have been able to create a queue. I will continue to troubleshoot. Thanks

…

On Mon, Sep 8, 2025 at 12:17 PM Michael Klishin ***@***.***> wrote: To clarify why the above setting can be important specifically for streams: Stream Client Connections <https://www.rabbitmq.com/docs/stream-connections>. — Reply to this email directly, view it on GitHub <#655 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABJ7QUQ5PZOMWDZ5WO3HVET3RWT3LAVCNFSM6AAAAACF56K6JSVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTIMZUGIZTSMI> . You are receiving this because you were mentioned.Message ID: ***@***.*** .com>