Personally, I've started just using mDNS/Bonjour for local devices. Comes preinstalled on most devices (may need a manual package on BSD/Linux servers) and doesn't require any configuration. Just type in devicename.local and let the network do the rest. You can even broadcast additional device names for different services, so you don't need to do plex.nas.local, but can just announce plex.local and nas.local from the same machine.

There's a theoretical risk of MitM attacks for devices reachable over self-signed certificates, but if someone breaks into my (W)LAN, I'm going to assume I'm screwed anyway.

I've used split-horizon DNS for a couple of years but it kept breaking in annoying ways. My current setup (involving the pihole web UI because I was sick of maintaining BIND files) still breaks DNSSEC for my domain and I try to avoid it when I can.

A bunch of out-of-the-box NAS manufacturers provide a web-based OS-like shell with file managers, document editors, as well as an "app store" for containers and services.

I see the traditional "RAID with a SMB share" NAS devices less and less in stores.

If only storage target mode[1] had some form of authentication, it'd make setting up a barebones NAS an absolute breeze.

[1]: https://www.freedesktop.org/software/systemd/man/257/systemd...

File history, sharing and user management are some of the common ones I can think of.

To me, it's a question of time and money efficiency. (Time is money.)

I can buy a NAS, whereby I pay money to enjoy someone else's previous work of figuring it out. I pay for this over and over again as my needs change and/or upgrades happen.

Or

I can build a NAS, whereby I spend time to figure it out myself. The gained knowledge that I retain in my notes and my tiny little pea brain gets to be used over and over again as needs change, and/or upgrades happen. And -- sometimes -- I even get paid to use this knowledge.

(I tend to choose the latter. YMMV.)

There are power meters like KWS-303L that will tell you how much manufacturers lie with their numbers.

For example my ancient tplink TL-WR842N router eats 15W standby or no, while my main box, fans, backlight, gpu, hdds and stuff -- about 80W idle.

Looking at Synology site the only power I see there is the psu rating, which is 90W for DS425. So you can expect real power consumption of about 30-40W. Which is typical for just about any NUC or a budget ATX motherboard with a low-tier AMD-something + a bunch of HDDs.

"Meant to" may indeed not be really accurate.

However, domains and host names were not designed to be particularly private and should not be considered secret, many things don't consider them private, so you should not put anything sensible in a host name, even in a network that's supposed private. Unless your private network is completely air-gapped.

Now, I wouldn't be surprised that hostnames were in fact originally expected to be explicitly public.

You don't need any auth to send an email from your domain, or in fact from any domain. Just set whatever `From` you want.

I've received many emails from `root@localhost` over the years.

Admittedly, most residential ISPs block all SMTP traffic, and other email servers are likely to drop it or mark it as spam, but there's no strict requirement for auth.

It should not, but it's usual to configure random services to send mails to users, for instance for password resets, or for random notifications.

Another thing usually sending mails is cron, but that should only go to the admin(s).

Some services might also display the host name somewhere in their UI.