Netdata for me, it reports stats and metrics for VMs and containers too, automatically, and it’s easy to install in Proxmox.

I used both, I ended up settling on searxng because Whoogle seemed to be unable to retain my settings. Might be something with my cookie configuration, but searxng has no problem remembering my preferences. If that is not a problem for you then they are comparable; Whoogle is pretty simple to get going and works well, searxng is slightly more complicated to set up (but not that much with docker) but has a ton more features.

I’ve been using Debian as my main server OS for a long time, but yeah I’ve started using Alpine for lightweight hosts for a single app/docker lately. Especially on proxmox with the pve-helper-scripts you can spin up an Alpine container or VM with Docker in a few seconds.

This is not a good idea unless you really know what you’re doing. High capacity batteries and high power circuits are pretty dangerous and there’s a surprising amount of complexity to build a reliable UPS. You’d probably have better luck modding an existing UPS (say from a flea market) to use a bigger battery if you are really desperate to save every dollar.

Plus making it yourself you probably won’t save any money unless you already have all of the tools required, which is pretty extensive if you wanna do things right/safely.

Related question for those of you running Proxmox… how do you back up the Proxmox host itself? Last time I looked into it the recommended solution was basically manually copy a few folders in /etc or do a full disk backup but that’s pretty unsatisfying. Currently I can easily restore any VMs that fail from backup with a few clicks, but if the SATADOM I installed Proxmox onto failed it’d be kind of fiddly to reconstitute and restore all the other settings/networking/etc.