Questions tagged [ptp]
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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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Incorrect PTP timestamps [closed]
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 ...
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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 ...
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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 ...
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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). ...
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No info found about `ethtool -T` output?
Nowhere I can find such info, to interpret the following number:
PTP Hardware Clock: 1
Most documentation I can find (e.g. from RedHat it shows 0).
What does it mean?
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How to Configure IPTABLES to allow PTP sync behind a bridge firewall
We have a Fedora machine with eth0(ip:10.321.xx)connected to intranet. The same machine has a eth1 with a few more linux boxes connected in a 192.xx network.
on the 10.321.xx n/w there is a PTP server....
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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 ...