You have just set the system clock correctly by hand and want the hardware clock to match, so the correction survives a reboot. Type the command, using its short option.
LPIC-1 Exam 102-500, objective 108. Essential system services easy
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Answer
Type the answer.
Accepted answers
hwclock -whwclock --systohc/sbin/hwclock -w/sbin/hwclock --systohc
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
hwclock -w is short for hwclock --systohc: write the system clock into the hardware clock. The reverse, hwclock -s (--hctosys), sets the system clock from the RTC and is what early boot does on systems without NTP. hwclock -r (--show) just prints the RTC. hwclock also records a drift factor and the UTC-versus-local-time setting of the RTC in /etc/adjtime; keeping the RTC in UTC is the recommendation on Linux-only machines because it removes daylight-saving ambiguity.
Where this comes from
- Cited
- LPI exam objective 108.1
- What it says
- Set the hardware clock from the correct system time.
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 108 and space the ones you get wrong.
More questions on this objective
- You corrected the running system's clock with `date -s`, but after the next power cycle the machine came back with the old wrong time. Which command copies the corrected system clock into the hardware (RTC) clock? machine-checked
- On a systemd-based distribution, which file determines the local time zone used by the C library when formatting times? machine-checked
- A host runs chrony as its NTP client. Which command shows the list of time sources chrony is currently talking to and how it rates each one? machine-checked
- In /etc/ntp.conf you find the line `server 0.pool.ntp.org iburst`. What does the `iburst` keyword do? machine-checked
- A minimal systemd host synchronises its clock with systemd-timesyncd. Which statement about that service is accurate? machine-checked
- On a systemd host, type the single command that turns on automatic network time synchronisation (do not include a path). machine-checked