As far as I can tell my Unraid box is connected to my home network just fine - it's always lived at 10.0.0.97:180 for over a year now. I use Xfinity for home internet and the Xfinity App reports it sees the NAS box at the same IP address as always (the NAS is connected to the modem via ethernet).

A few weeks ago though I was suddenly unable to load up the unraid GUI at http://10.0.0.97:180/Dashboard, Firefox on my desktop returns an 'Unable to connect' error page and Edge on my phone has a similar error, 'Hmmm... can't reach this page'. This morning I tried plugging in a monitor to my NAS however after doing so I don't get any signal from the box and nothing displays even after also plugging in a mouse and keyboard and trying some inputs.

I'm also able to see the server and it reports being Online via Unraid Connect.

Any ideas what might be preventing me from seeing the Unraid GUI but at the same time everything installed on it seems to work for other devices on the network (such as PLEX)?

Monitor may not work if the server was already booted, if you also don't have SSH access, you may need to force a reboot. You can also try a quick press of the power button, then see if the server can do a clean shutdown.

I'm back with a recap - it's been a wild ride.

First off, the issue with no display was a case of me being a moron - I kept taking the HDMI cord from the monitor and plugging it into the NAS box (the other end of the cable was in my primary tower PC). I never fully realized this for a long time, I RMA'd my CPU and got a new one, then even ended up buying a new motherboard and only after reassembling the NAS did I realize how dumb I was.

With the display issue resolved I still had the base problem of the NAS being unreachable via browser or even directly on the NAS box itself (though all the docker containers were still running and accessible by outside services). After I rebuilt the NAS box everything magically started working, but as I'll discuss later that was of course just coincidence and had more to do with restarting the physical box and having the stars align correctly more than anything I did to fix it.

Finally, my rebuild was working great for a month or so before the issue came back, I couldn't access Unraid via browser nor on the box itself though all services/dockers were running and behaved fine (e.g. PLEX from the TV and whatnot). I may end up getting chided for how I ended up solving it but here it is: I prompted ChatGPT my issue ('services running on my NAS work fine but when I try to login to the machine at <ipdadress>:180 all my browsers say the connection was refused or that they can't establish a connection'). ChatGPT ran me through some diagnostics, it had me check that SSH was enabled (it wasn't, and it walked me through how to re-enable it first) and then determined a little while later that the server was of course online but unreachable via browser, specifically the port my NAS uses for the web interface had no service running on it (whereas UnRaid's GUI service, emhttp, should be running). ChatGPT determined that the culprit was probably that nginxproxy was hijacking the gui's port's prior to emhttp being able to bind to it - the AI walked me through first disabling docker at startup (to ultimately kill nginxproxy), killing emhttpd, then restarting the NAS box - on restart the browser connection and local GUI worked again - from there I restarted Docker and now everything is working as expected.

So TL;DR -

1. No Display - I was a moron and used the wrong end of the HDMI cable, that's why I had no display

2. No Access to GUI Via Browser or via NAS box - NGINX Proxy Manager had hijacked the webgui port on boot at some point and caused UnRAID's GUI service to be unable to bind to the port as expected - killing docker, restarting the NAS box, then re-enabling docker fixed everything