Last resolver error: produced zero addresses

Hi, I see a lot of these in the logs:

Dec 13 08:13:04 PM 12-14-2020 04:13:04.039 [ERROR] 14 UNAVAILABLE: last connection error: connection error: desc = “transport: Error while dialing dial tcp XX.XX.X.XXX:9080: connect: no route to host”; last resolver error: produced zero addresses.

I redacted the IP address but you can see it in the logs.

This coincided with a report from an end-user that connectivity was lost.

I can’t tell if this is related to, but it does seem interesting in the context.

I restored connectivity by manually redeploying.

Hi @azaafoo,

It looks like there might be a misconfiguration in your application’s error handling. If a redeploy fixed the problem, and based on what I can tell from the gRPC resolver code, it looks like the resolver was just incorrectly enumerating addresses.

Is this a recurring problem for you, or was it a one-time problem that was permanently resolved by restarting? Also, have you confirmed that you are using a recent version of the grpc-go library, especially one newer than the problem listed in that StackOverflow post?

hmm so after further research, I’m leaning to the conclusion that these are server generated grpc errors (there are references to these in the spec). I’m going to pursue that line of inquiry. Thanks for your time.