Bug 1117702 – SHM refclock doesn't support nanosecond resolution

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Bug 1117702 - SHM refclock doesn't support nanosecond resolution

Summary:	SHM refclock doesn't support nanosecond resolution

Status:	CLOSED ERRATA

Aliases:	None

Product:	Red Hat Enterprise Linux 7
Classification:	Red Hat
Component:	ntp (Show other bugs)
Sub Component:
Version:	7.0
Hardware:	Unspecified Unspecified

Priority	unspecified Severity unspecified
Target Milestone:	rc
Target Release:	---
Assigned To:	Miroslav Lichvar
QA Contact:	Jakub Prokes
Docs Contact:

URL:
Whiteboard:
Keywords:

Depends On:
Blocks:	1191019 1205796 1095800 1117704
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Reported:	2014-07-09 04:41 EDT by Miroslav Lichvar
Modified:	2015-11-19 03:37 EST (History)
CC List:	7 users (show)

See Also:
Fixed In Version:	ntp-4.2.6p5-20.el7
Doc Type:	Enhancement
Doc Text:	Support for nanosecond resolution has been added to the SHM reference clock. Prior to this update, when a Precision Time Protocol (PTP) hardware clock was used as a time source to synchronize the system clock (for example, with the timemaster service from the linuxptp package), the accuracy of the synchronization was limited due to the microsecond resolution of the SHM protocol. The nanosecond extension in the SHM protocol now allows sub-microsecond synchronization of the system clock.
Story Points:	---
Clone Of:
Clones:	1117704 (view as bug list)
Environment:
Last Closed:	2015-11-19 03:37:19 EST
Type:	Bug
Regression:	---
Mount Type:	---
Documentation:	---
CRM:
Verified Versions:
Category:	---
oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---

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External Trackers
Tracker	ID	Priority	Status	Summary	Last Updated
Network Time Protocol	1232	None	None	None	Never
Red Hat Product Errata	RHSA-2015:2231	normal	SHIPPED_LIVE	Moderate: ntp security, bug fix, and enhancement update	2015-11-19 04:03:04 EST

Groups: None (edit)

Description Miroslav Lichvar 2014-07-09 04:41:06 EDT

Description of problem:
The SHM refclock in ntpd is limited to microsecond resolution. In 4.2.7 development a nanosecond extension was added to the protocol. This can be useful to improve accuracy of the synchronization with PTP clocks and phc2sys from linuxptp.

https://bugs.ntp.org/show_bug.cgi?id=1232

Version-Release number of selected component (if applicable):
4.2.6p5-18

Comment 9 errata-xmlrpc 2015-11-19 03:37:19 EST

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHSA-2015-2231.html

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