tree: 28b05adbda84c30fa7ed1f4e109eaa1199db8a8d [path history] [tgz]
  1. 10_11/
  2. image-setup-notes.txt


Go's Mac builders run at Mac hosting provider, MacStadium. We have a VMware cluster with 10 physical Mac Minis on which we run two VMs each.

In addition to 20 Mac VMs, we also run one 1 Linux VM that's our bastion host & runs various services.

Bastion Host

The bastion host is and can be accessed via:

$ ssh -i ~/keys/id_ed25519_golang1

(Where id_ed255519_golang1 is available from http://go/go-builders-ssh)

It also runs:

  • a DHCP server for the 20 Mac VMs to get IP addresses from (systemd unit isc-dhcp-server.service, so watch with journalctl -f -u isc-dhcp-server.service)

  • the makemac daemon daemon (systemd unit makemac.service, so watch with journalctl -f -u makemac). This monitors the build coordinator ( as well as the VMware cluster (via the govc CLI tool) and makes and destroys Mac VMs as needed. It also serves plaintext HTTP status at which used to be accessible in a browser, but recent HSTS configuration on * means you need to use curl now. But that‘s a good way to see what it’s doing remotely, without authentication.

  • WireGuard listening on port 51820, because OpenVPN + Mac‘s built-in VPN client is painful and buggy. See config in /etc/wireguard/wg0.conf. This doesn’t yet come up on boot. It's a recent addition.


The method of last resort to access the cluster, which works even if the bastion host VM is down, is to VPN to our Cisco something gateway.

TODO: put this info somewhere. It's currently circulated in email between Brad, Russ, and Dmitri in an email with some subject “macOS VM info”.

VMware web UI

Once you've connected to either OpenVPN or WireGuard, you can hit the VMware web UI at:

(Alternatively, ssh -D to the bastion host to make a SOCKS tunnel and configure your browser to send proxy through that SOCKS tunnel.)

Adding a New Image

When a new version of macOS is released:

  • Ensure that the version of vSphere deployed on MacStadium supports the new version of macOS. If it doesn't, either request that MacStadium upgrade the cluster or seek guidance from them about the upgrade path.

  • Clone the latest macOS version on vSphere and upgrade that version to the desired macOS version as per the instructions.

  • If a completely new image is required, follow the images setup notes in order to add a new image.


Common techniques to debug: