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Version: v0.8.x

Custom buildkit addresses

You may need to specify a custom address using the --addr flag. Here are the supported formats:

  • unix:///path/to/buildkit.sock - Connect to buildkit over unix socket.
  • tcp://$BUILDKIT_ADDR:$PORT - Connect to buildkit over TCP. (not recommended for security reasons)
  • docker://<docker connection spec> - Connect to docker, currently only unix sockets are supported, e.g. docker://unix:///var/run/docker.sock (or just docker://).
  • docker-container://my-buildkit-container - Connect to a buildkitd running in a docker container.
  • buildx://my-builder - Connect to a buildx builder (or buildx:// for the currently selected builder). Note: only container-backed buildx instances are currently supported
  • nerdctl-container://my-container-name - Similar to docker-container but uses nerdctl.
  • podman-container://my-container-name - Similar to docker-container but uses podman.
  • ssh://myhost - Connect to a buildkit instance over SSH. Format of the host spec should mimic the SSH command.
  • kubepod://mypod - Connect to buildkit running in a Kubernetes pod. Can also specify kubectl context and pod namespace (kubepod://mypod?context=foo&namespace=notdefault).

Buildkit Connection Examples​

Option 1: Connect using defaults​

copa patch -i docker.io/library/nginx:1.21.6 -r nginx.1.21.6.json -t 1.21.6-patched

Option 2: Connect to buildx​

docker buildx create --name demo
copa patch -i docker.io/library/nginx:1.21.6 -r nginx.1.21.6.json -t 1.21.6-patched --addr buildx://demo

Option 3: Buildkit in a container​

export BUILDKIT_VERSION=v0.12.4
docker run \
    --detach \
    --rm \
    --privileged \
    --name buildkitd \
    --entrypoint buildkitd \
    "moby/buildkit:$BUILDKIT_VERSION"

copa patch -i docker.io/library/nginx:1.21.6 -r nginx.1.21.6.json -t 1.21.6-patched --addr docker-container://buildkitd

Option 4: Buildkit over TCP​

export BUILDKIT_VERSION=v0.12.4
export BUILDKIT_PORT=8888
docker run \
    --detach \
    --rm \
    --privileged \
    -p 127.0.0.1:$BUILDKIT_PORT:$BUILDKIT_PORT/tcp \
    --name buildkitd \
    --entrypoint buildkitd \
    "moby/buildkit:$BUILDKIT_VERSION" \
    --addr tcp://0.0.0.0:$BUILDKIT_PORT

copa patch \
    -i docker.io/library/nginx:1.21.6 \
    -r nginx.1.21.6.json \
    -t 1.21.6-patched \
    -a tcp://0.0.0.0:$BUILDKIT_PORT

Option 5: Buildkit over TCP with mTLS​

export BUILDKIT_VERSION=v0.12.4
export BUILDKIT_PORT=8888
docker run \
    --detach \
    --rm \
    --privileged \
    -p 127.0.0.1:$BUILDKIT_PORT:$BUILDKIT_PORT/tcp \
    --name buildkitd \
    --entrypoint buildkitd \
    -v $PWD/.certs:/etc/buildkit/certs \
    "moby/buildkit:$BUILDKIT_VERSION" \
    --addr tcp://0.0.0.0:$BUILDKIT_PORT \
    --tlscacert /etc/buildkit/certs/daemon/ca.pem \
    --tlscert /etc/buildkit/certs/daemon/cert.pem \
    --tlskey /etc/buildkit/certs/daemon/key.pem

copa patch \
    -i docker.io/library/nginx:1.21.6 \
    -r nginx.1.21.6.json \
    -t 1.21.6-patched \
    -a tcp://0.0.0.0:$BUILDKIT_PORT
    --cacert /path/to/ca-certificate \
    --cert  /path/to/buildkit/client/cert \
    --key /path/to/buildkit/key