Cannot run maas-regiond without /bin/maas-rack

I was trying to setup a secondary region controller by itself without it also being a rack controller.

sudo apt install maas-region-api maas-dns

Configured /etc/maas/regiond.conf to point to the database on the first region controller and restarted maas-regiond.

But the maas-regiond service on the secondary region controller keeps printing stack traces because it wants to perform network discovery. The 'maas-rack' command is not present so it cannot run.

The only package that includes 'maas-rack' is the 'maas-rack-controller' package, that will also make this controller a rack controller. I do not want this region controller to be a rack controller, I just want it to be a region controller.

Seems that MAAS has a dependency problem on itself.

Stacktrace:

2017-07-06 14:53:33 provisioningserver.utils.services: [critical] mDNS observation process failed.

Traceback (most recent call last):
Failure: twisted.internet.error.ProcessTerminated: A process has ended with a probable error condition: process ended with exit code 1.
2017-07-06 14:54:33 provisioningserver.utils.services: [info] Neighbour observation process for eth0 started.
2017-07-06 14:54:33 provisioningserver.utils.services: [info] mDNS observation process started.
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: Upon execvpe b'maas-rack' [b'maas-rack', b'observe-arp', b'eth0'] in environment id 140183375294728
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: :Traceback (most recent call last):
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: File "/usr/lib/python3/dist-packages/twisted/internet/process.py", line 430, in _fork
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: environment)
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: File "/usr/lib/python3/dist-packages/twisted/internet/process.py", line 508, in _execChild
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: os.execvpe(executable, args, environment)
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: File "/usr/lib/python3.5/os.py", line 624, in execvpe
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: _execvpe(file, args, env)
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: File "/usr/lib/python3.5/os.py", line 660, in _execvpe
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: raise last_exc.with_traceback(tb)
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: File "/usr/lib/python3.5/os.py", line 650, in _execvpe
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: exec_func(fullname, *argrest)
2017-07-06 14:54:33 provisioningserver.utils.services: [info] observe-arp[eth0]: FileNotFoundError: [Errno 2] No such file or directory: b'/bin/maas-rack'
2017-07-06 14:54:33 provisioningserver.utils.services: [critical] Neighbour observation process for eth0 failed.