PolyBase Error: gRPC Connection Failed (StatusCode="Unavailable") When Creating External Table

Rocky Linux Help & Support
1

Hello Rocky Linux Community,

I am encountering a blocking issue when trying to execute a CREATE EXTERNAL TABLE statement using PolyBase on SQL Server hosted on Rocky Linux. The query fails with a gRPC subchannel connectivity error.

**Error Message:
**
Msg 110813, Level 16, State 1, Line 144
Status(StatusCode=“Unavailable”, Detail=“failed to connect to all addresses”, DebugException=“Grpc.Core.Internal.CoreErrorDetailException: {“created”:”@1787018813.182000000",“description”:“Failed to pick subchannel”,“file”:“…\src\core\ext\filters\client_channel\client_channel.cc”,“file_line”:3135,“referenced_errors”:[{“created”:“@1787018813.182000000”,“description”:“failed to connect to all addresses”,“file”:“…\src\core\lib\transport\error_utils.cc”,“file_line”:163,“grpc_status”:14}]}")

Context:

  • This error triggers exactly during the execution of CREATE EXTERNAL TABLE.

  • The configuration of the EXTERNAL DATA SOURCE itself completes without any instant errors, but the actual table generation throws this gRPC internal subchannel failure.

    Environment details :

  • Rocky Linux Version: Rocky Linux 9.8 (Blue Onyx)

  • Application Framework: sQL Server / Polybase

2

Do Polybase have a forum where you can ask this question, as this is a Polybase problem. Rocky doesn’t provide Polybase - from a quick google it looks like a Microsoft product.

3

you can increase debug info, by setting env vars
https://stackoverflow.com/questions/68217975/grpc-method-call-error-failed-to-pick-subchannel
in their case it was a certificate issue