Thank you for all the answers.
Actually Markus has pointed to the right direction, the CMOS battery is out of power. That’s also why I have to switch on secure boot every time even I set it on before.
Just can’t think of this since it’s a relatively new machine (2 years), but it’s been off for some time so that’s why the battery drains so quickly.
Anyway thank you again for all the help.
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From: Manfred Schwarb
Hello,
This little weird problem has confused me for some time, but I can't find any related situation from Google.
Since quite some time ago when I boot up, the system time is never correct at first. It shows the date which is a month or two before, and the time is always 8am. But after 3-4 mins the system time becomes normal and accurate again. So every time when I logged into the system and opened a browser window immediately, the browsers would give a NET::ERR_CERT_DATE_INVALID complaint.
This sounds a little strange, I would go for the responses of Markus and Carlos first. I had a very similar issue with a new mainboard, the RTC was way off. I did quite some research to fix it, see below. But in the end, I did a BIOS update, and all was fine... The RTC can be adjusted by tick (coarse tuning) and frequency (fine tuning). The thing is, NTP is quite deficient, in that it can only adjust the frequency. So if your RTC is way off, NTP has problems. You then have to set the tick manually at startup (e.g. in /etc/init.d/boot.local) with adjtimex --tick xxxxx --frequency 0 With a correct tick set, NTP then is able to do its work. To find out the correct tick, you can run adjtimex --compare=50 -i 10 --host 0.pool.ntp.org and let it run for a while. If the suggested tick (second last column) is outside of a range of 9995..10005 or so you should consider setting the tick at startup, to help NTP to do its work. Cheers, Manfred
It looks like it's something related to the NTP daemon. I am using Network manager under Plasma desktop with WiFi enabled. I'm not sure if only after Network Manager starts up my wifi then the NTP daemon begins to sync time, which in turn causes this problem? But this set up is quite common and I couldn't find any similar cases from other users, so maybe there's another reason?
Thanks in advance.
Regards,
Charlie