I've browsed through so many different sites and found so much contradictory information. As I am getting tired of this and do belive this question affects many other users, so I would like to collect the "once and for all times" answer. Unfortunately, the documentation on MaaS and Juju is ... well, not the best, sorry to say that.

What are the minimum system requirements for setting up a MaaS cluster, which is going to be orchestrated with juju-jitsu?

Do they need to have the exact system specifications or can I just combine different hardware?

What are the minimum requirements for the master machine?

E.g. "You need at least 8GB of RAM, a dual core CPU with at least 3.0 GHz."

How many machines to I need to deploy MaaS on?

I've read six machines, nine machines, and so on. I clearly want to know: "You need one for the Master and e.g. five nodes."

Do I need to attach as many NICs (network interface cards) to my master machine as there are nodes, or can I simply attach two NICs and a switch?

One NIC for connecting to the internet, one for handling the MaaS tasks, connected to a switch, which connects my nodes to the master?

Is Juju now ready for local deployment?

The last time I experimented with juju and had to reboot my machine, the services orchestrated by juju were gone. This was an issue I also found on the official juju site. Unfortunately, as mentioned above, the documentation is not the best, so I could not find the necessary info on that again. So:

Can I use juju on a local environment or will a reboot break my setup?