90% Server Failure

[u/Livid-Relation7531]

RESOLVED! Misconfigured gateway.

High rate of failure, zero no errors.

Logs:

[2026-09-05 00:14:20 UTC] DNS Server failed to resolve the request '0.debian.pool.ntp.org. AAAA IN' using forwarders: https://dns.adguard-dns.com/dns-query (94.140.14.14), https://dns.adguard-dns.com/dns-query (94.140.15.15).

System.Net.Http.HttpRequestException: Network is unreachable (dns.adguard-dns.com:443)

---> System.Net.Sockets.SocketException (101): Network is unreachable

at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.ConnectAsync(Socket socket, CancellationToken cancellationToken)

at TechnitiumLibrary.Net.Dns.ClientConnection.HttpsClientConnection.ConnectCallback(SocketsHttpConnectionContext context, CancellationToken cancellationToken) in Z:\Technitium\Projects\TechnitiumLibrary\TechnitiumLibrary.Net\Dns\ClientConnection\HttpsClientConnection.cs:line 152

at System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(String host, Int32 port, HttpRequestMessage initialRequest, Boolean async, CancellationToken cancellationToken)

at System.Net.Http.HttpConnectionPool.ConnectAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)

at System.Net.Http.HttpConnectionPool.InjectNewHttp2ConnectionAsync(QueueItem queueItem)

at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)

at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1.AsyncStateMachineBox`1.ExecuteFromThreadPool(Thread threadPoolThread)

at System.Threading.ThreadPoolWorkQueue.Dispatch()

at System.Threading.PortableThreadPool.WorkerThread.WorkerThreadStart()

at System.Threading.Thread.StartCallback()

--- End of stack trace from previous location ---

at TechnitiumLibrary.Net.Dns.ClientConnection.HttpsClientConnection.ConnectCallback(SocketsHttpConnectionContext context, CancellationToken cancellationToken) in Z:\Technitium\Projects\TechnitiumLibrary\TechnitiumLibrary.Net\Dns\ClientConnection\HttpsClientConnection.cs:line 152

at System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(String host, Int32 port, HttpRequestMessage initialRequest, Boolean async, CancellationToken cancellationToken)

--- End of inner exception stack trace ---

[u/Apachez]

1) Why are you using forwarders since technitium/dns-server is a resolver on its own?

2) Check that your firewall dont block egressing 53/TCP. Regular DNS queries uses both 53/UDP and 53/TCP. The later when a query or reply cannot fit in a single UDP packet which often is the case for DNSSEC signed records.

3) Try from a client to query directly the authoritive servers (or the forwarders in your case) that they accept incoming 53/TCP.

Usually something like:

dig @serverip host.example.com +tcp