On 15/11/2018 16:45, Anand Buddhdev wrote:

Hi folks,

RHEL 7 documentation says that if either ntp or chrony is running on a system, then it will enable the kernel feature to sync system time to the hardware clock every 11 minutes. This needs the CONFIG_RTC_SYSTOHC option to be set.

However, it looks like this option is not set for CentOS kernels:

# fgrep CONFIG_RTC_SYSTOHC /boot/config-3.10.0-862.14.4.el7.x86_64 # CONFIG_RTC_SYSTOHC is not set

This explains why on some of our servers, the hardware clock is out of sync with the system time.

Does anyone know why this option is not enabled for CentOS kernels?

Because it is not enabled on RHEL kernels.

Regards, Anand