factory.CreateConnection() generates a "None of the endpoints were reachable"

[fahadash]

We have a web application trying to connect with an intention to publish to a RabbitMQ Server within the same network and we are getting the following exception.

Exception Occurred
Type: RabbitMQ.Client.Exceptions.BrokerUnreachableException
Message: None of the specified endpoints were reachable
Stack Trace:    at RabbitMQ.Client.ConnectionFactory.CreateConnection(IEndpointResolver endpointResolver, String clientProvidedName) in /_/projects/RabbitMQ.Client/client/api/ConnectionFactory.cs:line 505
   at Org.Product.Dependency.Concrete.Queuing.RabbitMqProdMessenger.SendMessage[TMessage](String hostname, String username, String password, String vhost, String target, TMessage message, Boolean targetIsExchange)
Source: RabbitMQ.Client

Inner Exception

Type: System.IO.IOException
Message: connection.start was never received, likely due to a network timeout
Stack Trace:    at RabbitMQ.Client.Framing.Impl.Connection.StartAndTune() in /_/projects/RabbitMQ.Client/client/impl/Connection.cs:line 1074
   at RabbitMQ.Client.Framing.Impl.Connection.Open(Boolean insist) in /_/projects/RabbitMQ.Client/client/impl/Connection.cs:line 707
   at RabbitMQ.Client.Framing.Impl.AutorecoveringConnection.Init(IFrameHandler fh) in /_/projects/RabbitMQ.Client/client/impl/AutorecoveringConnection.cs:line 646
   at RabbitMQ.Client.ConnectionFactory.CreateConnection(IEndpointResolver endpointResolver, String clientProvidedName) in /_/projects/RabbitMQ.Client/client/api/ConnectionFactory.cs:line 495
Source: RabbitMQ.Client

We have tried shipping a simple console application to the server that does some publishing and that app works fine but when the web application uses the same code it gets the above exception. I tried looking for clues in the code in this repository and found none. Any help in this will be appreciated.

[michaelklishin]

There is a dedicated doc guide on how to efficiently narrow down connectivity issues. You haven't provided any code so we cannot suggest anything else.

[michaelklishin]

This is a guess since we have no code to work with but if you use the default credentials, be aware of the fact that for obvious security reasons that user can only connect from localhost. All inbound
connections that send at least one byte of data will be logged by RabbitMQ.
If nothing is logged, that means you are not connecting to the correct port or inbound TCP connections is rejected for some reason (e.g. by a firewall).

[fahadash]

@michaelklishin Thank you for your reply. We have crossed most of the things in that list already. The same code when run through a console app works fine, it only has issues when it is run under IIS app pool. Here is our code

var factory = new ConnectionFactory()
{
    HostName = hostname,
    UserName = username,
    Password = password,
    VirtualHost = vhost,
    Port = 5672
};

var connection = factory.CreateConnection();

[JLopeDeB]

@fahadash Hello! I wonder if you ever solved this issue, since my team is facing a similar problem. Everything works but the call from the code. Even works from other servers as well.

Thank you.

[lukebakken]

If you would like assistance, start a new discussion, and include the following information:

• RabbitMQ and Erlang version
• Operating system for RabbitMQ and your client application.
• RabbitMQ.Client library version
• .NET version
• Application runtime (Windows Server, IIS, etc)
• FULL stack traces, and logs from RabbitMQ

[youxiaotian]

@michaelklishin Thank you for your reply. We have crossed most of the things in that list already. The same code when run through a console app works fine, it only has issues when it is run under IIS app pool. Here is our code

var factory = new ConnectionFactory()
{
    HostName = hostname,
    UserName = username,
    Password = password,
    VirtualHost = vhost,
    Port = 5672
};

var connection = factory.CreateConnection();

hello , if my code is run under IIS app pool . how to fix it?

[lukebakken]

@youxiaotian - please see this discussion.

Nobody has yet provided me with EXACT instructions for how to reproduce this issue using IIS. I don't have the time to guess how to set IIS up and reproduce this issue.