I'm curious as to why someone would need to do that short of having a bunch of users and a small office at home. Or maybe managing the family's computers is easier that way?
I was considering a domain controller (biased towards linux since most servers/VMs are linux) but right now, for the homelab, it just seems like a shiny new toy to play with rather than something that can make life easier/more secure. There's also the problem of HA and being locked out of your computer if the DC is down.
Tell me why you're running it and the setup you've got that makes having a DC worth it.
Personally I use FreeIPA for my LDAP. I like that I can create sudoers rules from one centralized place and manage ssh keys across all clients. Granted I could just use Ansible I suppose, which is how I update multiple distributions in my network and online but I like that I can just change SSH keys and sudoers from one place easily instead of changing tasks/roles. I also usually run cockpit even on my non-Red Hat distros with SSH keys just so I don't have to log into everything though it is somewhat limited outside of the Red Hat sphere.
If you don't want to use ProxMox or some other specialized HyperVisor ecosystem, you can also use Cockpit to manager your VMs along with your Pods. I wish there'd be more attention to it for features because it feels like it could do a lot more.
I also don't really worry about locking myself out for two reasons:
I use SSH keys.
I also have a break-glass local account on every system...with SSH keys. If its on your local network, you can use VNC/VM console/Remote Desktop with a local account while only allowing SSH with keys if you'd like. Just make sure if you're going to allow remote access outside of your network that you never forward the VNC/RDP ports. For SSH when I do this I always pick some random port -- never default and never common ones like 2222 to at least keep my logs less noisy from the botnet auto attacks.
For my online VPS' I use a firewall with geoIP from Maxmind and drop all ports but 443 from the world, except for whatever country I'm in. I drop all packets from certain countries that seem to auto-attack more often than others. I try to drop packets from all known (to me) Shodan scanners. If I'm not traveling I just restrict all other ports to my public IP's subnet though my IP hasn't changed for years. For status checking services like StatusCake, I use the "push" method instead using a simple cron job with curl instead of relying on servers around the world checking my ports. In this case, the services just check that my server has successfully hit them within X minutes to be "up".
Thank you for your experience using FreeIPA, your comment really got me re-thinking about AD, about trust setups and if I really needed a Windows domain controller other than for learning. Being able to manage Sudoers centrally is fantastic!
I plan to use XCP-ng as my hypervisor.
Unfortunately, I didn't quite catch how using SSH keys will keep you from getting locked out if your domain controller goes down. That sounds exactly like what I want, and great idea having a spare account on each machine!
The SSH keys don't help me if I get locked out of a Domain Controller unless you're using OpenSSH (which is now a native feature you can turn on). In that case you can actually still log into the DC via command line because it authenticates based on authorized_keys and not the LDAP of the DC. I actually do this on the enterprise, not because I may get locked out but because it is just convenient. Granted you'll have to execute powershell on the command line once in to use the AD cmdlets.
On the other hand when you create a DC now-a-days (Server 2019...I don't remember if this is asked in the wizard when in Server 2016) you can create a "Directory Services Restore Mode" password which is basically a local admin account on the DC that you can log into only when the DC is booted into safe mode. You'll be asked to create it when you promote your DC.
Hey, I'd like to ask you one more thing: is it possible to set up short-term credentials which can be provisioned and invalidated automatically with policies? I'm looking towards an idea of a self-hosted AWS STS without installing a secrets manager like Conjur and I think it should technically be possible with FreeIPA. Please let me know what you think.