Dns.GetHostEntryAsync may produce an error such as "(0x00002AF9): No such host known"

[xuzimianxzm]

🐛 Bug Report

🔬 How To Reproduce

Steps to reproduce the behavior:

This problem may not be easy to reproduce. It is related to the underlying system. I use a custom compiled Linux system. It may be because it does not have a DNS service. Although I set the MQTT server connection address to an IPv4 IP address, it still throws an exception in this line of code in the HiveMQClientSocket.cs file:
IPHostEntry ipHostEntry = await Dns.GetHostEntryAsync(this.Options.Host).ConfigureAwait(false);

Code sample

System.Net.Sockets.SocketException (0x00002AF9): No such host known。
at System.Net.Dns.GetHostEntryOrAddressesCore(IPAddress address, Boolean justAddresses, AddressFamily addressFamily, Nullable1 startingTimestamp) at System.Net.Dns.GetHostEntryCore(IPAddress address, AddressFamily addressFamily, Nullable1 startingTimestamp)
at System.Net.Dns.<>c.b__33_1(Object s, Int64 startingTimestamp)
at System.Net.Dns.<>c__DisplayClass39_01.<RunAsync>b__0(Task <p0>, Object <p1>) at System.Threading.Tasks.ContinuationResultTaskFromTask1.InnerInvoke()
at System.Threading.Tasks.Task.<>c.<.cctor>b__281_0(Object obj)
at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---

Environment

Customer Linux

[github-actions]

Hello @xuzimianxzm, thanks for contributing to the HiveMQ community! We will respond as soon as possible.

[pglombardo]

Hi @xuzimianxzm - what value did you provide for Host in HiveMQClientOptions?

[xuzimianxzm]

Hi @xuzimianxzm - what value did you provide for Host in HiveMQClientOptions?

Thank you very much for replying to my question so quickly. The HiveMQClientOptions I provided are as follows:
var options = new HiveMQClientOptionsBuilder() .WithBroker("192.168.0.4") .WithPort(DefaultPort) .WithClientId($"xxx-{DateTime.Now.Ticks}") .WithAutomaticReconnect(true) .Build();

[pglombardo]

Thanks @xuzimianxzm. I'm traveling but once I'm back I'll see if I can test this out and potentially find a work around soon.

[xuzimianxzm]

Thanks @xuzimianxzm. I'm traveling but once I'm back I'll see if I can test this out and potentially find a work around soon.

That's awesome, thank you again, your work and your code means so much to me.

[pglombardo]

Hi @xuzimianxzm - this should be fixed now via #187. I'll release a new package with this fix very soon.

[pglombardo]

Hi @xuzimianxzm - the fix for this is released in v0.22.1. Could you try out that package and let me know if it fixes the issue for you?

[xuzimianxzm]

HiveMQClientSocket

Hi @pglombardo
After testing, this issue has been fixed. Thank you so much, your response speed is amazing.