Requesting more documentation on "cannot set inq" error

[darren...@unity3d.com]

We're debugging an issue which occurs only when our gRPC service is running in a Kubernetes cluster (behind GCP LB & NGINX Ingress), but not in a standalone container (in GCE).

One thing we're seeing is a number of these errors:

D0228 02:48:47.380209 140008409261824 /var/local/git/grpc/src/core/lib/iomgr/tcp_posix.cc:1258: cannot set inq fd=210 errno=92

Whilst I've found the origin of INQ and the source of that error message in the gRPC code, that doesn't yet get me closer to understanding the underlying issue (or if this is related to the actual cause of failure).

Would it be possible to get further explanation on why this error might occur?

Thank you

[veb...@google.com]

"cannot set inq fd=210 errno=92" isn't an error message but a debug message. setsockopt in the code may or may not succeed depending on the underlying kernel support. Presumably it isn't supported when running in a Kubernetes cluster.