Red Hat Bugzilla – Bug 2160
xntp3 does not actually set PLL update mode
Last modified: 2008-05-01 11:37:49 EDT
The 5.2 xntp3 RPM, despite being happy to set the kernel
clock and track time and stuff, does not actually appear
to use the kernel-level PLL facilities. For example,
adjtimex --print will report 'status: 64' (clock
Among other problems, this will cause the kernel not
to update the hardware CMOS clock every so often. This
will in turn cause a machine to potentially jump a lot
of time when rebooted.
The best cure for this appears obscure to me,
unfortunately. I have become lost in a twisty
maze of source RPMs and autoconf.
Running Red Hat 6.0 with a 2.2 kernel, adtimex --print reports
status: 1 (PLL updates enabled), so the PLL code appears functional
in 2.2 kernels.
Setting the CMOS clock can be done within xntp, but is not an
essential part of xntpd functionality. Since xntp3 syncs to reference
clocks quite well even without the PLL code, you can set your
CMOS clock manually with other utilities whenever xntpd shows
an acceptably small offset to a reference clock.