can you fake *nix uptime?

Question

Just curious, Can you fake an uptime, for instance increase it to 10 years?

I have tried changing system time, and it won't do this trick.

Answer 1

Have a look at this utility: UptimeFaker.

Answer 2

Yeah, you should be able to attach a gdb to the running kernel, and hack the uptime value. You'd need to know where it was kept, and have a symbols file. I am assuming here, that uptime is held in something statically allocated.

Alternatively, write a small kernel module which hacks the uptime when you load it (and immediately unloads again).

Answer 3

alias uptime='echo " 11:07:17 up 10 BILLION YEARS!,  4 users,  load average: 0.38, 0.52, 0.41"'

If you want to get extra-fancy, you could take the actual uptime output and modify that.