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Atlas probes not reporting NTP results on ntp0.testdns.nl ?
by Marco Davids (SIDN) 18 Jul '25

18 Jul '25

Dear list, If anyone knows, or is able to figure out, why most (but not all) Atlas probes don’t report results for NTP measurements to ntp0.testdns.nl, I’d appreciate your insights. Examples: https://atlas.ripe.net/measurements/116922622/ https://atlas.ripe.net/measurements/116946257/ https://atlas.ripe.net/measurements/116830921/ Ping works: https://atlas.ripe.net/measurements/116921717/ Thanks in advance. -- Marco

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Re: Atlas probes not reporting NTP results on ntp0.testdns.nl ?
by Marco Davids (SIDN) 17 Jul '25

17 Jul '25

Hi Joachim, Thank you for looking into this! On Thu, 17 Jul 2025 15:30:35 +0200 Joachim Kroß wrote: > It seems the explicitly misbehaving server has been replaced by a more > sane one (albeit apparently not synchronized) Oh, yes that's correct - sorry for that. I started doing some tests with an NTPv5 enabled Chrony server. The NTP simulator is still available on another server though, albeit IPv6 only (because such VM's are so much cheaper): ntp1.testdns.nl. For those interested; my simple NTP simulator is here: https://github.com/mdavids/ntptools/tree/main/go/fake-ntp-server A version that allows to simulate jitter and clock drift is here: https://github.com/mdavids/ntptools/tree/main/go/fake-ntp-server-2 Just a few simple experiments, mostly the result of a bit of vibe coding. -- Marco

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Asking for credits for a university project
by Serban Orza 16 Jul '25

16 Jul '25

Hello, Atlas community! I am Serban Orza, a second-year Computer Science student at Delft University of Technology. Together with another 4 students, we are working on an open-source project that measures the accuracy and reliability of NTP servers. We already implemented the basics, but we would like to integrate RIPE Atlas to have a global perspective and to avoid the bias of a single measurement point. We would appreciate it a lot if somebody could provide us with some RIPE API credits to perform measurements and analyze the reachability of NTP servers. My account at RIPE NCC is on this email: orza(a)student.tudelft.nl Thank you! Serban

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sw-probe reducing syslog messages
by Hans Mayer 14 Jul '25

14 Jul '25

Dear All, I am running the package ripe-atlas 1.5-3 on Debian 12 bookworm with probe id 1010735. Is there a way to reduce the syslog messages for really necessary events like errors ? Kind regards Hans --

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software probe disconnected: REGINIT exit with error
by Marek Küthe 09 Jul '25

09 Jul '25

Hello, For a few hours now, my two software probes (#1008711 and #1008669) are no longer connected. I have attached the log. I build the software probe myself [1] and use a somewhat hardened systemd unit [2]. Does anyone know what I could do? Greetings Marek Küthe [1] https://codeberg.org/mark22k/dn42-router/src/commit/ae9b7cc8c36a7cb0dd9ce8d… [2] https://codeberg.org/mark22k/dn42-router/src/commit/ae9b7cc8c36a7cb0dd9ce8d… -- Marek Küthe m.k(a)mk16.de er/ihm he/him

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Offset of NTP measurement
by Marco Davids (SIDN) 09 Jul '25

09 Jul '25

I noticed a discrepancy between the output of my own tool and RIPE Atlas. My tool reports the offset as a negative value, while RIPE Atlas shows a positive one. For example: https://atlas.ripe.net/measurements/115803954/results Any thoughts? -- Marco

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Location quantisation?
by Ray Bellis 08 Jul '25

08 Jul '25

In an effort to find and report probes with incorrect geolocation, I'm rather curious to find out what's special about a lake just west of Wichita (Kansas) that results in it having 11 probes in the middle of it? I suspect some sort of very coarse location quantisation, yet the probes there are not just distributed all over the US, but I also see a probe from Madrid and another from near Ljubljana. cheers, Ray

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Probe areas
by Yohan Prod'homme 07 Jul '25

07 Jul '25

Hello, When you start a measurement, you can specify an area to chose probes from. These areas are like "West", "North-Central", "South-East"... What do they corresponds to? If I use the "West" area, this is the west of what? Of the europe? Because "west of the world" barely makes any sense to me, and I can't find any documentation about these areas. I feel like I'm missing something obvious, so I'd be grateful if someone can enlighten me :) Thanks, Yohan

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Probe down ?
by Colin Johnston 30 Jun '25

30 Jun '25

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traceroute with specific udp target port
by julien.piccaluga 25 Jun '25

25 Jun '25

Hello, I’m developing a Proof of Location project and have a use case requiring a traceroute on a specific UDP port. It appears that traceroute only supports selecting a target port for TCP. Are there any undocumented or lesser-known methods to achieve this with UDP? Regards Julien Piccaluga Mobile: +41 (0) 78 832 36 20 Envoyé avec un e-mail sécurisé [Proton Mail](https://proton.me/mail/home).

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