As of F16, Fedora uses `chrony` (chronyd.service) as the default time daemon. Chrony monitors and offsets local clock skew, making it superior for machines without a constant connection to an ntp server. It also effectively changes the system clock for even very large time changes, where ntpd would require manual adjustment. The System administrator's guide should be updated to reflect this.
The following sections, and references to them, should be updated:
2.2.3, “Configuring the Network Time Protocol”
Thanks, Pete. We are aware of this change and as a matter of fact, Stephen Wadeley is already working on this particular piece of documentation.
First draft was sent to SME late last week, Hope to have something worth proof reading in a few days.
First draft ready in repo.
I like it, very comprehensive and well presented. Only a couple thoughts:
The instructions for starting, stopping, enabling, and disabling the service are universal, and this section could refer to the "Services and Daemons" section. There could be points in favor of either a reference or a restatement, and obviously this would be your call.
Later, I was a little confused by "By default, rtcsync will inform the kernel the system clock is synchronized and the kernel will update the real-time clock in 11 minute intervals." After a little reading, I found that 'rtcsync' is a chronyd config file directive, not a separate application, and that I was somehow confusing 'intervals' of small clock updates every 11 minutes with 11 minute 'increments'. A minor point, but it could be made more clear.
 grep -A9 -m1 4.2.44 /usr/share/doc/chrony-1.27/chrony.txt
Thank you for the feedback.
Paragraph 1: A matter of style so I will leave that to the guide owner.
BTW, I was taught to rather include sort descriptions than to make readers look elsewhere (subjective of course). Also, its easier to find instructions if you have short task descriptions with suitable headings.
Paragraph 2: I think I took the SME too literally. I'll propose this:
By default, the rtcsync directive is present in the /etc/chrony.conf file. This will inform the kernel the system clock is kept synchronized and the kernel will update the real-time clock every 11 minutes.
The very helpful Miroslav Lichvar has approved my wording as in c#5.
Is jhradile happy with the new headings and structure?
I'd like to document chronyd in the Security Guide as well.
Also, chronyd shouldn't replace ntpd in the documentation as ntpd is still being shipped, although it is no longer default.
Point 1: I think this BZ is not the place to discuss the pros and cons of duplicating content.
Point 2: I can only find a mention of ntpd in the appendix "The sysconfig Directory". I see that I have cut off some still useful commands at the end of the chapter "Configuring the Date and Time".
I will add an ntpd chapter ASAP and improve the end of chapter "Configuring the Date and Time".
I have added a chapter describing the use ntpd to configure ntp
I have improved the end of the "Configuring the Date and Time" chapter.
(In reply to Stephen Wadeley from comment #9)
> I have added a chapter describing the use ntpd to configure ntp
> I have improved the end of the "Configuring the Date and Time" chapter.
Can you provide a patch (or just the DocBook file) for this change so I can add it to the Security Guide, please?
Duplicating content is not a good idea.
Please link to the chapters on time (ntp, chrony, and ptp)
Please discuss the issue of duplication and linking in the Fedora docs meeting.
You've addressed all of my concerns and provided good coverage on this topic, thank you Stephen.