I tried to get the diagnostics, but downloading never gets past here:

 

 

Parity check has been stuck here for at least 2 hours:

 

 

And I have this disk with a ton or errors:

 

 

I do have a 6tb disk on hand I could use to replace disk 5, but I wanted to check in what the best way to proceed was before making any changes.

Can you access any other page in the webUI?

I can open all of the pages, I can even start my Plex docker, but it won't play anything and errors out when trying to browse. 

 

I can open \\zelda in file explorer in Windows and see my shares, but none of them can be opened.

 

The parity check is still at 98.6%, it's been there for about 12 hours

 

Should I try to cancel the parity check?

Try going to   Tools   >>>   System Log    go to the bottom of the page and click on the 'Download' button.  See if you can capture the syslog that way.  IF you do get one, upload it in a new post.

 

Also, try to see if you setup the Syslog Server before you reboot:     https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/2/?tab=comments#comment-781601

 

Wait for three or four hours and see if you get any other advice before you reboot.  When you do reboot, get the Diagnostics file and have it ready to upload.  I have the feeling, a parity check will occur on startup so leave the Syslog Server running.  You want to be able to capture the syslog on a continuous basis in case the parity check does not complete properly. 

I'll give that a try, but I probably won't be able to do anything now until Sunday. Would grabbing the diagnostics before starting the array or before the freeze up occurs help?

15 minutes ago, mostlydave said:

Would grabbing the diagnostics before starting the array or before the freeze up occurs help?

It would tell us about your hardware and configuration, then syslog server could add to that by maybe showing what is happening when things get hung.