Computer security is a wide-ranging and important discipline impossible to cover completely here. There are, however, some relatively simple steps you can take to harden the security of your MAAS installation on your rack and region controllers.
Warning: There are too many use cases and operating systems to make any meaningful security suggestions in this context for your deployed machines.
This should go without saying, but you should pick good passwords and store them
securely (e.g. in a KeePassX password database). User administration should be
performed via the web UI and the
root user passwords should only be
shared with administrators.
MAAS doesn't (yet) support SSL natively. Using a reverse SSL proxy, however, you can restrict outside access to your region controllers (which serve the MAAS API) by using NGINX or Apache to accept HTTPS requests, then using HTTP internally to communicate with MAAS normally via port 5240 and finally serving results back through HTTPS to the requester.
See SSL for configuration examples.
MAAS configuration files should be set to have permission
640: readable by
logins belonging to the
maas group and writeable only by the
regiond.conf file contains the login credentials for the
PostgreSQL database used by MAAS to keep track of all machines, networks, and
chmod 640 /etc/maas/rackd.conf chmod 640 /etc/maas/regiond.conf
-rw-r----- 1 root maas 90 Sep 27 14:13 rackd.conf -rw-r----- 1 root maas 157 Sep 27 14:14 regiond.conf
The Rack controller page contains a list of ports used by MAAS for communications between rack and region controllers. Consider setting your firewall on your rack and region controllers to disallow communication on all ports except those used by MAAS.
When you add a new rack or region controller, for example, by installing the MAAS
snap and running
maas init --mode rack, MAAS asks for a shared secret it will
use to communicate with the rest of MAAS. (This secret is also exposed in the web
UI when you click the 'Add rack controller' button on the Controllers page.)
This secret is stored in a plain text file. MAAS automatically generates this secret when you install initially, i.e. when your first region controller is initially run.
You should also verify that any 'secret' files on all region and rack
600 or readable and writeable only by the 'maas' user.
sudo chmod 600 /var/lib/maas/secret
-rw------- 1 maas maas 32 Sep 27 14:15 /var/lib/maas/secret