I thought this would be a simple question but I haven't been able to find an answer anywhere.

Does anyone know at what point the system uptime rolls over to 0 again (I'm assuming there's a finite number of days, perhaps 999, then it resets to 0 like a car odometer?)

We're troubleshooting a firewall that as far as we know didn't go down in the last few years, however only shows an uptime of less than a month. Thanks!