55 lines
2.5 KiB
Markdown
55 lines
2.5 KiB
Markdown
# Troubleshooting gRPC
|
|
|
|
This guide is for troubleshooting gRPC implementations based on C core library (sources for most of them are living in the `grpc/grpc` repository).
|
|
|
|
## Enabling extra logging and tracing
|
|
|
|
Extra logging can be very useful for diagnosing problems. It can be used to increase the amount of information
|
|
that gets printed to stderr.
|
|
|
|
## GRPC_VERBOSITY
|
|
|
|
<!-- BEGIN_GOOGLE_INTERNAL_DOCUMENTATION
|
|
GRPC_VERBOSITY has been disabled for internal usage and will not work anymore.
|
|
If anyone wants to debug, we need to set verbose logs using absl.
|
|
END_GOOGLE_INTERNAL_DOCUMENTATION -->
|
|
|
|
<!-- BEGIN_OPEN_SOURCE_DOCUMENTATION -->
|
|
`GRPC_VERBOSITY` is used to set the minimum level of log messages printed by gRPC (supported values are `DEBUG`, `INFO` and `ERROR`). If this environment variable is unset, only `ERROR` logs will be printed. `ERROR` is recomeded for production systems.
|
|
<!-- END_OPEN_SOURCE_DOCUMENTATION -->
|
|
|
|
## GRPC_TRACE
|
|
|
|
<!-- BEGIN_GOOGLE_INTERNAL_DOCUMENTATION
|
|
GRPC_VERBOSITY has been disabled for internal usage and will not work anymore.
|
|
If anyone wants to debug, we need to set verbose logs using absl.
|
|
END_GOOGLE_INTERNAL_DOCUMENTATION -->
|
|
|
|
`GRPC_TRACE` can be used to enable extra logging for some internal gRPC components. Enabling the right traces can be invaluable
|
|
for diagnosing for what is going wrong when things aren't working as intended. Possible values for `GRPC_TRACE` are listed in [Environment Variables Overview](doc/environment_variables.md).
|
|
Multiple traces can be enabled at once (use comma as separator).
|
|
|
|
```
|
|
# Enable debug logs for an application
|
|
GRPC_VERBOSITY=debug ./helloworld_application_using_grpc
|
|
```
|
|
|
|
```
|
|
# Print information about invocations of low-level C core API.
|
|
# Note that trace logs of log level DEBUG won't be displayed.
|
|
# Also note that most tracers user log level INFO, so without setting
|
|
# GPRC_VERBOSITY accordingly, no traces will be printed.
|
|
GRPC_VERBOSITY=info GRPC_TRACE=api ./helloworld_application_using_grpc
|
|
```
|
|
|
|
```
|
|
# Print info from 3 different tracers, including tracing logs with log level DEBUG
|
|
GRPC_VERBOSITY=debug GRPC_TRACE=tcp,http,api ./helloworld_application_using_grpc
|
|
```
|
|
|
|
Known limitations: `GPRC_TRACE=tcp` is currently not implemented for Windows (you won't see any tcp traces).
|
|
|
|
Please note that the `GRPC_TRACE` environment variable has nothing to do with gRPC's "tracing" feature (= tracing RPCs in
|
|
microservice environment to gain insight about how requests are processed by deployment), it is merely used to enable printing
|
|
of extra logs.
|