[CentOS] Boot time in wtmp is not correct

Tue Oct 12 16:46:25 UTC 2021
Simon Matter <simon.matter at invoca.ch>


> When I do who -b; uptime I get
> system boot  2021-10-12 17:05
>  16:36:09 up 30 min,  1 user,  load average: 0.00, 0.00, 0.00
> As you can see the boot time reported by the last command is ahead.
> I have noted it is  one hour ahead after a reboot.
> I have checked the system time in the BIOS  before booting Linux and it is
> correct.

I don't know how exactly it comes but I guess it has something to do with
local vs. system time. You have UTC as timezone but because of DST it's
one hour apart.

What does last report?

On my test system I find the reboot which is shown in the who -b output in
the last output, and the uptime reported by last again matches with the
uptime output.