A number of environment variables can be used to configure the behavior of the library. There are also functions to configure this behavior in code. The environment variables are convenient when troubleshooting problems.
Endpoint Overrides
GOOGLE_CLOUD_CPP_ATTACHED_CLUSTERS_ENDPOINT=...overrides theEndpointOption(which defaults to "
GOOGLE_CLOUD_CPP_AWS_CLUSTERS_ENDPOINT=...overrides theEndpointOption(which defaults to "
GOOGLE_CLOUD_CPP_AZURE_CLUSTERS_ENDPOINT=...overrides theEndpointOption(which defaults to "
GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc: turns on tracing for most gRPC calls. The library injects an additional Stub decorator that prints each gRPC request and response. Unless you have configured your own logging backend, you should also setGOOGLE_CLOUD_CPP_ENABLE_CLOGto produce any output on the program's console.
See Also
google::cloud::LoggingComponentsOptionGOOGLE_CLOUD_CPP_TRACING_OPTIONS=...: modifies the behavior of gRPC tracing, including whether messages will be output on multiple lines, or whether string/bytes fields will be truncated.
See Also
google::cloud::GrpcTracingOptionsOptionGOOGLE_CLOUD_CPP_ENABLE_CLOG=yes: turns on logging in the library, basically the library always "logs" but the logging infrastructure has no backend to actually print anything until the application sets a backend or they set this environment variable.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[[["\u003cp\u003eThe latest release candidate version is 2.37.0-rc, with numerous previous versions ranging down to 2.11.0 also listed.\u003c/p\u003e\n"],["\u003cp\u003eEnvironment variables can be used to configure library behavior, particularly useful for troubleshooting, and can override endpoint defaults for Attached, AWS, and Azure clusters.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc\u003c/code\u003e setting enables tracing for gRPC calls, printing requests and responses when used with \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eGOOGLE_CLOUD_CPP_TRACING_OPTIONS\u003c/code\u003e adjusts gRPC tracing behavior like message formatting and field truncation, and \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG=yes\u003c/code\u003e activates logging output to the console.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e is used in examples and integration tests, although it has no effect in the library.\u003c/p\u003e\n"]]],[],null,["Version 2.29.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/gkemulticloud/latest/gkemulticloud-env)\n- [2.41.0](/cpp/docs/reference/gkemulticloud/2.41.0/gkemulticloud-env)\n- [2.40.0](/cpp/docs/reference/gkemulticloud/2.40.0/gkemulticloud-env)\n- [2.39.0](/cpp/docs/reference/gkemulticloud/2.39.0/gkemulticloud-env)\n- [2.38.0](/cpp/docs/reference/gkemulticloud/2.38.0/gkemulticloud-env)\n- [2.37.0](/cpp/docs/reference/gkemulticloud/2.37.0/gkemulticloud-env)\n- [2.36.0](/cpp/docs/reference/gkemulticloud/2.36.0/gkemulticloud-env)\n- [2.35.0](/cpp/docs/reference/gkemulticloud/2.35.0/gkemulticloud-env)\n- [2.34.0](/cpp/docs/reference/gkemulticloud/2.34.0/gkemulticloud-env)\n- [2.33.0](/cpp/docs/reference/gkemulticloud/2.33.0/gkemulticloud-env)\n- [2.32.0](/cpp/docs/reference/gkemulticloud/2.32.0/gkemulticloud-env)\n- [2.31.0](/cpp/docs/reference/gkemulticloud/2.31.0/gkemulticloud-env)\n- [2.30.0](/cpp/docs/reference/gkemulticloud/2.30.0/gkemulticloud-env)\n- [2.29.0](/cpp/docs/reference/gkemulticloud/2.29.0/gkemulticloud-env)\n- [2.28.0](/cpp/docs/reference/gkemulticloud/2.28.0/gkemulticloud-env)\n- [2.27.0](/cpp/docs/reference/gkemulticloud/2.27.0/gkemulticloud-env)\n- [2.26.0](/cpp/docs/reference/gkemulticloud/2.26.0/gkemulticloud-env)\n- [2.25.1](/cpp/docs/reference/gkemulticloud/2.25.1/gkemulticloud-env)\n- [2.24.0](/cpp/docs/reference/gkemulticloud/2.24.0/gkemulticloud-env)\n- [2.23.0](/cpp/docs/reference/gkemulticloud/2.23.0/gkemulticloud-env)\n- [2.22.1](/cpp/docs/reference/gkemulticloud/2.22.1/gkemulticloud-env)\n- [2.21.0](/cpp/docs/reference/gkemulticloud/2.21.0/gkemulticloud-env)\n- [2.20.0](/cpp/docs/reference/gkemulticloud/2.20.0/gkemulticloud-env)\n- [2.19.0](/cpp/docs/reference/gkemulticloud/2.19.0/gkemulticloud-env)\n- [2.18.0](/cpp/docs/reference/gkemulticloud/2.18.0/gkemulticloud-env)\n- [2.17.0](/cpp/docs/reference/gkemulticloud/2.17.0/gkemulticloud-env)\n- [2.16.0](/cpp/docs/reference/gkemulticloud/2.16.0/gkemulticloud-env)\n- [2.15.1](/cpp/docs/reference/gkemulticloud/2.15.1/gkemulticloud-env)\n- [2.14.0](/cpp/docs/reference/gkemulticloud/2.14.0/gkemulticloud-env)\n- [2.13.0](/cpp/docs/reference/gkemulticloud/2.13.0/gkemulticloud-env)\n- [2.12.0](/cpp/docs/reference/gkemulticloud/2.12.0/gkemulticloud-env)\n- [2.11.0](/cpp/docs/reference/gkemulticloud/2.11.0/gkemulticloud-env) \n\nEnvironment Variables\n=====================\n\nA number of environment variables can be used to configure the behavior of the library. There are also functions to configure this behavior in code. The environment variables are convenient when troubleshooting problems.\n\nEndpoint Overrides\n------------------\n\n- `GOOGLE_CLOUD_CPP_ATTACHED_CLUSTERS_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"\n- `GOOGLE_CLOUD_CPP_AWS_CLUSTERS_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"\n- `GOOGLE_CLOUD_CPP_AZURE_CLUSTERS_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"\n\n###### See Also\n\n[`google::cloud::EndpointOption`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1EndpointOption.html)\n\nLogging\n-------\n\n`GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc`: turns on tracing for most gRPC calls. The library injects an additional Stub decorator that prints each gRPC request and response. Unless you have configured your own logging backend, you should also set `GOOGLE_CLOUD_CPP_ENABLE_CLOG` to produce any output on the program's console.\n\n###### See Also\n\n[`google::cloud::LoggingComponentsOption`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1LoggingComponentsOption.html)`GOOGLE_CLOUD_CPP_TRACING_OPTIONS=...`: modifies the behavior of gRPC tracing, including whether messages will be output on multiple lines, or whether string/bytes fields will be truncated.\n\n###### See Also\n\n[`google::cloud::GrpcTracingOptionsOption`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1GrpcTracingOptionsOption.html)`GOOGLE_CLOUD_CPP_ENABLE_CLOG=yes`: turns on logging in the library, basically the library always \"logs\" but the logging infrastructure has no backend to actually print anything until the application sets a backend or they set this environment variable.\n\n###### See Also\n\n[`google::cloud::LogBackend`](https://cloud.google.com/cpp/docs/reference/common/latest/classgoogle_1_1cloud_1_1LogBackend.html)\n\n###### See Also\n\n[`google::cloud::LogSink`](https://cloud.google.com/cpp/docs/reference/common/latest/classgoogle_1_1cloud_1_1LogSink.html)\n\nSetting the Default Project\n---------------------------\n\n`GOOGLE_CLOUD_PROJECT=...`: is used in examples and integration tests to configure the GCP project. This has no effect in the library."]]