Cilium Proxy

Envoy proxy for Cilium with minimal Envoy extensions and Cilium policy enforcement filters. Cilium uses this as it's host proxy for enforcing HTTP and other L7 policies as specified in network policies for the cluster. Cilium proxy is distributed within the Cilium images.

Building

Cilium proxy is best built with the provided build containers. For a local host build consult the builder Dockerfile for the required dependencies.

Container builds require Docker Buildkit and optionally Buildx for multi-arch builds. Builds are currently only supported for amd64 and arm64 targets. For arm64 both native and cross compile on amd64 are supported. Container builds produce container images by default. These images can not be run by themselves as they do not contain the required runtime dependencies. To run the Cilium proxy the binary /usr/bin/cilium-envoy needs to be copied from the image to a compatible runtime environment, such as Ubuntu 18.04 or 20.04.

The provided container build tools work on both Linux and macOS.

To build the Cilium proxy in a docker container for the host architecture only:

make docker-image-envoy

Depending on hour host CPU and memory resources a fresh build can take an hour or more. Docker caching will speed up subsequent builds.

If your build fails due to a compiler failure the most likely reason is the compiler running out of memory. You can mitigate this by limiting the number of concurrent build jobs by passing environment variable BAZEL_BUILD_OPTS=--jobs=2 to make. By default the number of jobs is the number of CPUs available for the build, and for some complex C++ sources this may be too much. Note that changing the value of BAZEL_BUILD_OPTS invalidates Docker caches for the build stages.

Multi-arch builds

Build target architecture can be specified by passing ARCH environment variable to make. Supported values are amd64 (only on amd64 hosts), arm64 (on arm64 or amd64 hosts), and multi (on amd64 hosts). multi builds for all the supported architectures, currrently amd64 and arm64:

ARCH=multi make docker-image-envoy

Builds will be performed concurrently when building for multiple architectures on a single machine. You most likely need to limit the number of jobs allowed for each builder, see the note above for details.

Docker builds are done using Docker Buildx by default when ARCH is explicitly passed to make. You can also force Docker Buildx to be used when building for the host platform only (by not defining ARCH) by defining DOCKER_BUILDX=1. A new buildx builder instance will be created for amd64 and arm64 cross builds if the current builder is set to default.

Buildx builds will push the build result to quay.io/cilium/cilium-envoy:<GIT_SHA> by default. You can change the first two parts of this by defining DOCKER_DEV_ACCOUNT=docker.io/me for your own docker hub account. You can also request the build results to be output to your local directory instead by defining DOCKER_BUILD_OPTS=--output=out, where out is a local directory name.

Using custom pre-compiled Envoy dependencies

Docker build uses cached Bazel artifacts from quay.io/cilium/cilium-envoy-builder:release-archive-latest by default. You can overrride this by defining BUILDER_IMAGE=<ref>:

ARCH=multi BUILDER_IMAGE=docker.io/me/cilium-envoy-archive make docker-image-envoy

Bazel build artifacts contain toolchain specific data and binaries that are not compatible between native and cross-compiled builds. For now the image ref shown above is for builds on amd64 only (native amd64, cross-compiled arm64).

Define NO_CACHE=1 to build from scratch, but be warned that this can take several hours.

Docker caching

By default the build also tries to pull Docker build caches from docker.io/cilium/cilium-dev:cilium-envoy-cache. You can override this with our own build cache, which you can also update with the CACHE_PUSH=1 definition:

ARCH=multi CACHE_REF=docker.io/me/cilium-proxy:cache CACHE_PUSH=1 make docker-image-envoy

NO_CACHE=1 can be used to disable docker cache pulling, but it also disables use of pre-built Bazel artifacts.`

In a CI environment it might be a good idea to push a new cache image after each main branch commit.

Updating the pre-compiled Envoy dependencies

Build and push a new version of the pre-compiled Envoy dependencies by:

ARCH=multi make docker-builder-archive

By default the pre-compiled dependencies image is tagged as quay.io/cilium/cilium-envoy-builder:release-archive-latest. You can override the first two parts of this by defining DOCKER_DEV_ACCOUNT=docker.io/me, or completely by defining BUILDER_IMAGE=<ref>.

Pre-compiled Envoy dependencies need to be updated only when Envoy version is updated or patched enough to increase compilation time significantly.

Updating the builder image

The required Bazel version typically changes from one Envoy release to another. To create a new builder image first update the required Bazel version at .bazelversion and then run:

ARCH=multi NO_CACHE=1 make docker-image-builder

The builder can not be cross-compiled as native build tools are needed for native arm64 builds. This means that for non-native builds QEMU CPU emulation is used instead of cross-compilation. If you have an arm64 machine you can create a Docker buildx builder to use it for native builds.

The builder image is tagged as "quay.io/cilium/cilium-envoy-builder:bazel-". Change the BUILDER_BASE ARG in Dockerfile to use the new builder and commit the result.

For testing purposes you can define DOCKER_DEV_ACCOUNT as explained above to push the builder into a different registry or account.

Running integration tests

To run Cilium Envoy integration tests in a docker container:

make docker-image-tests

This runs the integration tests after loading Bazel build cache for Envoy dependencies from quay.io/cilium/cilium-envoy-builder:test-archive-latest. Define NO_CACHE=1 to compile tests from scratch.

This command fails if any of the integration tests fail, printing the failing test logs on console.

Note that cross-compiling is not supported for running tests, so specifying ARCH is not supported.

Updating the pre-compiled Envoy test dependencies

Build and push a new version of the pre-compiled test dependencies by:

make docker-tests-archive

By default the pre-compiled test dependencies image is tagged as quay.io/cilium/cilium-envoy-builder:test-archive-latest. You can override the first two parts of this by defining DOCKER_DEV_ACCOUNT=docker.io/me, or completely by defining BUILDER_IMAGE=<ref>.

Pre-compiled Envoy test dependencies need to be updated only when Envoy version is updated or patched enough to increase compilation time significantly.

Updating generated API

Cilium project vendors the Envoy xDS API, including Cilium extensions, from this repository. To update the generated API files, run:

rm -r go/envoy/*
make api

rm is needed to clean up API files that are no longer generated for Envoy. Do not remove files at go/cilium/ as some of them are not automatically generated!

Commit the results and update Cilium to vendor this new commit.