C-Ares cannot find DNS Servers #19954
Description
What version of gRPC and what language are you using?
C# .Net Standard 2.0
gRPC 1.21.0
What operating system (Linux, Windows,...) and version?
Windows 10 Version 1809
What runtime / compiler are you using (e.g. python version or version of gcc)
vbcs.exe via MSBUILD
What did you do?
If possible, provide a recipe for reproducing the error. Try being specific and include code snippets if helpful.
The client is unable to resolve DNS address of the server unless the GRPC_DNS_RESOLVER environment variable to "native".
What did you expect to see?
I expected gRPC to work out of the box, I would not need to set the GRPC_DNS_RESOLVER environment variable.
What did you see instead?
C-Ares "Could not contact DNS servers" .
Make sure you include information that can help us debug (full error message, exception listing, stack trace, logs).
Below are the gRPC logs, any help is greatly appreciated!
I0814 18:33:56.089860 0 T:\src\github\grpc\workspace_csharp_ext_windows_x64\src\core\ext\filters\client_channel\resolving_lb_policy.cc:318: resolving_lb=000002315BE67890: resolver transient failure: {"created":"@1565822036.090000000","description":"DNS resolution failed","file":"T:\src\github\grpc\workspace_csharp_ext_windows_x64\src\core\ext\filters\client_channel\resolver\dns\c_ares\dns_resolver_ares.cc","file_line":358,"grpc_status":14,"referenced_errors":[{"created":"@1565822036.088000000","description":"C-ares status is not ARES_SUCCESS: Could not contact DNS servers","file":"T:\src\github\grpc\workspace_csharp_ext_windows_x64\src\core\ext\filters\client_channel\resolver\dns\c_ares\grpc_ares_wrapper.cc","file_line":244,"referenced_errors":[{"created":"@1565822036.088000000","description":"C-ares status is not ARES_SUCCESS: Could not contact DNS servers","file":"T:\src\github\grpc\workspace_csharp_ext_windows_x64\src\core\ext\filters\client_channel\resolver\dns\c_ares\grpc_ares_wrapper.cc","file_line":244}]}]}