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Questions tagged [ptp]

Precision Time Protocol is used to synchronize clocks with sub-microsecond accuracy.

Precision Time Protocol is used to synchronize clocks with sub-microsecond accuracy.

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Is PTP really more precise than NTP? If so, why?

I have read quite a bit about NTP and PTP time keeping protocols. While many sources claim that PTP is more precise than NTP for that type of granularity - the reason is not as clear. Why can't NTP be just as accurate if a stratum 0 reference clock…
Palace Chan
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Why PTP uses Sync-followup pairs?

The PTP (Precision Time Protocol), uses Sync message then Follow-up message, as described in the article "Understanding the IEEE 1588 Precision Time Protocol". I don't understand why do we need Follow-up message in part A in Figure 1. I think that…
Yousf
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Is there a way to disable Precision Time Protocol (PTP) on Intel I211 Gigabit w/igb driver?

I have an ASUS Pro WS X570-ACE motherboard, with AMD Ryzen 5700G, with on-board Intel I211 Ethernet, running driver igb ver. 5.11.0-27. This also has a Realtek onboard Ethernet, but that is disabled in BIOS. The OS is Linux Mint 20.2 running kernel…
NoRainDropsInTheSky
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Network cards supporting PTP one-step-sync

We currently want to setup a PTP Grandmaster using ptp4linux on a Linux host. The slave devices rely on PTP one-step-sync but we haven't found any purchaseable network card on the marked which has this feature (ethtool has to report…
Tik0
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Packets difference between PTP and gPTP

I'm trying to understand few things about gPTP (IEEE 802.1AS). I am using the open source implementation by AVnu (https://github.com/AVnu/gptp). I looking on the packets using Wireshark, and they are parsed as PTPv2 packets. Is there any protocol…
Shir
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PTP (or NTP) and Domain Controller clock sync

We need a high precision (1ms) clock synchronization across multiple machines which are part of the domain. The idea is to use a PTP solution. Is it possible to setup a computer which is part of the domain to use a different time synchronization…
Kimi
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How to configure a redundant PTP server

I have a Sonoma GPS time server and a server, which should synchronise itself to the GPS clock, and serve as a fallback option. The time should be synchronised using PTP (Precision-Time-Protocol). This is the current configuration: GPS dedicated…
Michael
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ptp time synchronization on centos6/rhel

I need to setup time synchronization using PTP (precision time protocol). I'll get server address. I found ptpd server (version 2.1). I created startup files in /etc/init.d. But wondering what options other than showing on which interface I should…
sashk
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Incorrect PTP timestamps

I have trouble syncing to Linux systems using PTP. Setup: Two PCBs with a BegleCore module and a DP83640 PHY are connected with each other over Ethernet. One board should act as the PTP master, the other as the slave. Debian 10, Kernel:…
11011100
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PTP support for RTL8125B-CG NIC in Ubuntu 20.04

I have an RTL8125B-CG NIC which, from what I gather from their product page, has hardware support for PTP. However, sudo ethtool -T does not detect any HW timestamping capabilities. I've tried with the r8169 driver and with the r8125 driver from…
eirik-ff
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Ignore chrony source with obviously wrong time

I have a robot and am using timemaster to start chrony and add a PTP source from my GPS. When I start the robot inside where it can't get a satellite fix, the GPS claims it is January 5th, 1980. As a result, I get a stratum 0 source that is selected…
Chris Showers
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Retrieving the current PTP settings of an Ubuntu machine

I have an Ubuntu machine (18.04) with PTPd installed. I want to write a script that can determine what PTP settings have been set previously. Specifically, I want to find information on the master PTP server that this machine is locked to (if it is…
Eliezer Miron
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Use of PTPd on RedHat/CentOS

I need to create a reliable and accurate synchronization between two CentOS 6 machines connected through a direct Ethernet connection. I've seen that on Linux several implementation of the IEEE 1588 Precision Time Protocol (PTP)…
Claudio
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tshark -T fields : any way to print interpreted values of numeric fields?

T-shark is a powerful command-line sibling of Wireshark, the packet capture tool. At the basic verbosity level, you get one text row per packet, with just some basic information. Example: tshark -n -i eth1 This yields: 1 0.000000000…
frr
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