Our self-hosted build runners are no longer working. I reached out to DigitalOcean and it seems the coreos-stable image has been removed due to it not being support by RedHat anymore.
The official documentation still references this image:
Is there an alternate image that works?
You can swap to the RancherOS image which has the slug rancheros and the username to connect is rancher instead of core.
eg. so your Machine options should look like
MachineOptions = ["digitalocean-image=rancheros", "digitalocean-ssh-user=rancher", "digitalocean-access-token=XXX", "digitalocean-region=sgp1", "digitalocean-size=c-2"]
Thanks! That seems to work.