[Bug 805661] Re: NO reference clock support. I need Oncore ref clock support in ntp.

[Hal Engel]

I added the following to /etc/apparmor.d/usr.sbin.ntpd

/var/log/ntp/ntp.log rw,
/var/log/ntpstats/clockstats rw,
/dev/oncore.serial.0 rw,
/dev/oncore.pps.0 r,

It will not create the log file in /var/log/ntp.  But it will do it in
/var/log even with the above changes.  When I run ntp configured to
create the log file in /var/log I get the following:

 6 Jul 13:44:06 ntpd[2220]: can't open /var/log/ntpstats/clockstats: Permission denied
 6 Jul 13:44:06 ntpd[2220]: can't open /var/log/ntpstats/clockstats: Permission denied
 6 Jul 13:44:06 ntpd[2220]: refclock_open /dev/oncore.serial.0: Permission denied
 6 Jul 13:44:06 ntpd[2220]: can't open /var/log/ntpstats/clockstats: Permission denied
 6 Jul 13:44:06 ntpd[2220]: 127.127.30.0 interface 127.0.0.1 -> (none)
 6 Jul 13:44:07 ntpd[2220]: running in unprivileged mode disables dynamic interface tracking

The PPS stuff is correctly configured and is running although I have not
fully automated it's startup and am starting it by hand.   Testing this
with:

testpps /dev/pps0

or

testpps /dev/oncore.pps.0

I get the correct results showing that the PPS system is active and that
the correct interrupts are being generated.

Also from past experience I know that running ntp in microsecond mode
against a nanokernel will result in fairly poor timekeeping.  With
everything in NANO mode this setup should keep the clock synced to with
in 2 microseconds of UTC worst case and most of the time it should
maintain offsets that are less than 1 microsecond.   But with ntp in
micro mode and a nanokernel my experience has been that offsets will get
as high as 100 microseconds and the clock will be unstable and poorly
synced.  This is not apparent when using Internet based time servers
since time errors are typically 3 orders of magnitude greater than we
expect to see with a local high precision reference clock (IE.
milliseconds vs. microseconds) and jitter is also in the milliseconds
range where I expect to see 1 microsecond jitter levels with this setup.

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https://bugs.launchpad.net/bugs/805661

Title:
  NO reference clock support.  I need Oncore ref clock support in ntp.

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