Please Help: Connection Refused from DSM, but can log in directly

[gmoniey]

I'm stuck and would love some suggestions as I've run out of ideas

 

I'm currently running 5.2-5644 and I can't get the DSM web UI to stay responsive. Essentially I reboot the NAS, and everything works as expected, I can log into the UI, perform actions, etc...then like clockwork about 5-10 minutes later, the UI is no longer responsive and when I reload the page I get a "ERR_CONNECTION_REFUSED" error.

 

Some additional info:

 

• Synology Assistant can still locate it, and says it is "Ready"
• I can directly log into it (when I attached a keyboard and monitor). When I'm logged in, I've tried looking for any information in the error logs, but haven't found anything (perhaps I'm looking in the wrong places).
• I've also tried restarting nginx, but that operation failed without any info as to why (also, no nginx error log). 
• I'm at a loss. More than anything I want to backup my data to a usb drive, before I mess with things, but I'm even running into trouble with that. I tried copying all the files over directly from the terminal to a usb drive, but ran into all sorts of permission problems when I connected it to another machine.
• When I run the SMART test, it doesn't show any error, but the DSM is never up long enough for the  disk partition analysis to finish. I wouldn't be surprised if a disk is having an issue, but I don't know which one (I have 4).

 

Any suggestions on where I can look to debug this issue?