The rbe_ubuntu2004_bazel7 directory contains the autogenerated toolchain configuration for linux RBE. Run generate_linux_rbe_configs.sh to regenerate.

The rbe_windows_vs2022_bazel7 directory contains the autogenerated toolchain configuration for windows RBE. The configuration was generated by the rbe_configs_gen tool (just as the linux RBE config), but since it's a windows configuration, it needs to be run on a windows machine.

In order to regenerate:

• Clone grpc repository in a kokoro debug windows VM (see internal documentation for how to create one)
• Run generate_windows_rbe_configs.sh to regenerate the configs locally on the VM.
• Copy the generated configs back to your workstation (e.g. via gcloud compute scp command)

Note that the bazel version denotes the bazel version that was used to generate the toolchain configuration. The configuration can be use with different bazel versions (as long as it works).

Also see go/rbe-windows-user-guide

The dockerfile/rbe_windows2019 directory contains the dockerfile to rebuild the docker image we use on RBE windows workers. See go/rbe-windows-user-guide.

Note that for linux, we use a docker image under tools/dockerfile (since for Linux RBE docker image is simply of the testing docker images we maintain)

On a kokoro debug windows VM, run the following:

• docker build -t us-docker.pkg.dev/grpc-testing/testing-images-public/rbe_windows2019 third_party/toolchains/dockerfile/rbe_windows2019
• To be able to authenticate when pushing the image to GAR, run gcloud auth configure-docker us-docker.pkg.dev
• docker push us-docker.pkg.dev/grpc-testing/testing-images-public/rbe_windows2019
• Update the generate_windows_rbe_configs.sh with the newly built & pushed image's SHA256 digest. (If you're using the Kokoro Windows VM, you need to run sed -i 's/\r$//' third_party/toolchains/generate_windows_rbe_configs.sh before running the script to remove \r characters that bash doesn't understand)
• Regenerate the Windows RBE toolchain with the instructions above.