Everything was fine up until four to five days ago. After a day or so running I get email notifications telling me that the system is hitting 85%+. If I don't reboot within an hour or so of getting the notifications it gets to the point where I can't log into the webui or even ssh into the machine.
So my only alternative at that point it forcing the machine to shut down via the button on the front.
I'm not sure where to start troubleshooting this issue as I don't fancy rebooting my machine every few days.