Deploying Mac executors requires a little extra love since the deployment process can't easily be automated via Kubernetes.
Deploying a BuildBuddy cluster
First you'll need to deploy the BuildBuddy app which serves the BuildBuddy UI, acts as a scheduler, and handles caching - which we still recommend deploying to a Linux Kubernetes cluster.
You can follow the standard Enterprise RBE Setup instructions to get your cluster up and running.
Mac environment setup
Once you have a BuildBuddy cluster deployed with RBE enabled, you can start setting up your Mac executors.
When starting with a clean Mac, you'll first need to make sure Xcode is installed. You can download Xcode from Apple's Developer Website (you'll need an Apple Developer account).
We recommend installing at least Xcode 12.2 (which is the default Xcode version used if no
--xcode_version Bazel flag is specified).
If installing on many machines, we recommend downloading the Xcode .xip file to a location you control (like a cloud storage bucket) and downloading from there using a simple curl command. This reduces the number of times you have to login to your Apple Developer account.
Once your .xip file is downloaded, you can expand it with the following command.
xip --expand Xcode_12.2.xip
You can then move it to your
Applications directory with the version number as a suffix (so multiple Xcode versions can be installed together and selected between using the
--xcode_version Bazel flag).
mv Xcode.app /Applications/Xcode_12.2.app
If this is the first Xcode version you're installing, you'll want to select it as your default Xcode version with:
sudo xcode-select -s /Applications/Xcode_12.2.app
You can then accept the license with:
sudo xcodebuild -license accept
And run the "first launch" with
sudo xcodebuild -runFirstLaunch
You'll likely want to install Homebrew on your fresh executor to make installing other software easier. You can install it with the following line:
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
Installing the BuildBuddy Mac executor
Now that the environment is configured, we can download and install the BuildBuddy Mac executor.
Download the BuildBuddy executor
The BuildBuddy executor binary can be downloaded with (make sure to update the version number to the lastest release):
curl -fSL https://github.com/buildbuddy-io/buildbuddy/releases/download/v2.3.0/executor-enterprise-darwin-amd64 -o buildbuddy-executor
Make the executor executable
In order to run the executor binary, we must first make it executable with:
chmod +x buildbuddy-executor
If you don't already have any launch agents installed, you'll need to make sure the
~/Library/LaunchAgents/ directory exits with:
mkdir -p ~/Library/LaunchAgents/
You'll also need a directory to store the executor's disk cache and execution roots. We recommend avoiding using the
/tmp directory since this is periodically cleaned up.
mkdir -p buildbuddy
Create config file
You'll need to create a
config.yaml with the following contents:
local_cache_size_bytes: 100000000000 # 100GB
Make sure to replace YOUR_USERNAME with your Mac username and YOUR_BUILDBUDDY_CLUSTER_URL with the grpc url the BuildBuddy cluster you deployed. If you deployed the cluster without an NGINX Ingress, you'll need to update the protocol to grpc:// and the port to 1985.
Create a Launch Agent .plist file
Now that everything is in place, we can create a LaunchAgent .plist file that tells Mac OS to keep the executor binary running on launch, and restart it if ever stops.
Make sure to replace YOUR_USERNAME with your Mac username and YOUR_MACS_NETWORK_ADDRESS with the IP address or DNS name of the Mac.
You can place this file in
<?xml version=\"1.0\" encoding=\"UTF-8\"?>
<!DOCTYPE plist PUBLIC \"-//Apple//DTD PLIST 1.0//EN\" \"http://www.apple.com/DTDs/PropertyList-1.0.dtd\">
Update Launch Agent plist permissions
You may need to update the file's permissions with:
chmod 600 ~/Library/LaunchAgents/buildbuddy-executor.plist
Start the Launch Agent
You can load the Launch Agent with:
launchctl load ~/Library/LaunchAgents/buildbuddy-executor.plist
And start it with:
launchctl start buildbuddy-executor
You can verify that your BuildBuddy Executor successfully connected to the cluster by live tailing the stdout file:
tail -f buildbuddy_stdout.log
When updating your BuildBuddy Executors, you should restart one executor at a time, waiting for the previous executor to successfully start up before restarting the next. This will insure that work in flight is successfully rescheduled to another executor.
You can check that an executor has successfully started by checking that its
readyz endpoint returns the string
if [ "$(curl -s -X GET http://localhost:8080/readyz?server-type=prod-buildbuddy-executor || true)" == "OK" ]; then
echo "Executor is ready"
Optional: Enable Autologin
If your Mac executor restarts for whatever reason, you'll likely want to enable auto login so the executor will reconnect after rebooting instead of getting stuck on a login screen.
There's a convenient
brew package called
kcpassword that makes this easy.
brew tap xfreebird/utils
brew install kcpassword
sudo enable_autologin "MY_USER" "MY_PASSWORD"
Optional: Install Java
If you're doing a lot of Java builds on your Mac executors that are not fully hermetic (i.e. rely on the system installed Java rather than the remote Java SDK shipped by Bazel), you can install the JDK with:
brew install --cask adoptopenjdk
Optional: Increase the maximum number of open files
Some builds will exceed the default maximum number of open files on the Mac executor (which is relatively low). You'll know if you're hitting this limit if you see an error message that looks like
too many open files in system.
You can increase this limit by running the following command:
sudo launchctl limit maxfiles 5000000 5000000