How do you give access to your management network

Hello all,

How is your management network accessed where you guys work?

Does it live off a firewall or router and only given access to certain machines? Or does it live completely isolated, and a server has remote connectivity + an interface to management?

What is the process like to gain access to the network to perform troubleshooting? What kind of remote services do you use to gain access, and what is process like to authenticate you?

I am curious as to how you guys set up your management network, as I will be setting one up soon and I want to know best practices and ideas.

Thanks for any tips,