First-time FreeIPA user here.

I've installed FreeIPA on Fedora 18 and have some Fedora 16 IPA clients.  
"ipa-server-install" on Fedora 18 and "ipa-client-install" on Fedora 16 both 
add the following stanza to /etc/ntp.conf:

server     # local clock
fudge stratum 10

This sets up an additional time source based on the local system's hardware 

According to http://www.ntp.org/ntpfaq/NTP-s-refclk.htm

> The LCL is no reference clock in reality; instead it simply refers to the 
> system time on the current machine. Therefore it should never be used, except 
> when the system time is synchronized by some means not visible by xntpd.

"synchronized by some means not visible by xntpd" means a GPS card or an atomic 
clock, hardware which most systems do not have available.  In my experience, 
including a local time source on typical PC hardware is a recipe for inaccurate 
timekeeping.  It can be especially problematic in a virtual environment.

Including a local source might make sense for IPA servers, but only if the 
source is externally synchronized.  At first I thought maybe the ntp 
configurator script had found some evidence of external synchronization on my 
server hardware, but then the same stanza appeared on my IPA clients, both of 
which are VMware Fusion guests.

As soon as the local clock source was added on my IPA server, its ntp clock 
offset was skewed by a second and a half from the network servers it was 
tracking, and it became worse until I removed the local source.

It seems to me that adding a local source automatically is a bad idea.  Anyone 
know why the IPA installers add this source?

(I also note that "ipa-client-install" does not disable chronyd, but I've only 
tried the client install script on Fedora 16).

Chuck Lever

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