May 2016 - ripe-atlas - mailman.ripe.net

Adding additional probes to existing measurement or exchange them
by Annika Wickert 18 May '16

18 May '16

Hi everybody, I just stumbled across this problem, that I want to exchange probes on a actual running measurement because some of the probes I defined 2weeks ago went offline. And I want other probes to take over their job. Is that possible in any way? Cheers, Annika Wickert

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USB drive
by Michael Ionescu 13 May '16

13 May '16

Hi all, I have a probe that's been down for several days now. I did contact RIPE about it, but support has been superficial. I also didn't yet find the level of technical detail I need in the information on the website and in this list's archives. The 8GB drive, when reformatted on a windows box with FAT32 as per support instructions, surprisingly only comes out with a 1GB partition. Inspecting the drive under linux, I find multiple partitions, with only the first containing an a fat32 filesystem: Platte /dev/sdc: 7927 MByte, 7927234560 Byte 244 Köpfe, 62 Sektoren/Spur, 1023 Zylinder, zusammen 15482880 Sektoren Einheiten = Sektoren von 1 × 512 = 512 Bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Festplattenidentifikation: 0xc3072e18 Gerät boot. Anfang Ende Blöcke Id System /dev/sdc1 2048 2099199 1048576 b W95 FAT32 /dev/sdc2 2099200 4196351 1048576 83 Linux /dev/sdc3 4196352 6293503 1048576 83 Linux On first glance, the others contain ext2 filesystems # fsck -N /dev/sdc? fsck von util-linux 2.20.1 [/sbin/fsck.vfat (1) -- /dev/sdc1] fsck.vfat /dev/sdc1 [/sbin/fsck.ext2 (2) -- /dev/sdc2] fsck.ext2 /dev/sdc2 [/sbin/fsck.ext2 (3) -- /dev/sdc3] fsck.ext2 /dev/sdc3 but on further inspections do not contain a valid magic number in their superblocks, so they are effectively unformatted. I would therefore suspect that they are not being used by the probe. Now the question: What is the correct layout supposed to look like (primary/secondary, size, ID, FS-type)? I would like to get my probe back up and running. Bonus question: What can I expect to find in point of files/data on the drive, that would tell me whether the probe was working correctly until I cut power and removed the drive? Thanks, Michael

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[dagstuhl seminar]: global measurements: practice and experience
by Bajpai, Vaibhav 12 May '16

12 May '16

Dear RIPE Atlas / MAT WG -- sorry for cross-posting. A SIGCOMM CCR article summarising the Dagstuhl seminar on ‘Global Measurements: Practice and Experience’ just came online [a]. Thought to share it with you: [a] http://www.sigcomm.org/sites/default/files/ccr/papers/2016/April/0000000-00… Background: ===================== We recently helped organise a Dagstuhl seminar on Global Measurements: Practice and Experience [b] from January 04 – 07, 2016. This was a followup of the seminar on Global Measurement Framework [c] which focused on the development of global Internet measurement platforms and associated metrics. [b] http://www.dagstuhl.de/16012 [c] http://www.dagstuhl.de/13472 The second seminar aimed at discussing the practical experience gained with building global measurement platforms. It brought together people who are actively involved in the design and maintenance of global measurement systems, who do research on the data delivered by global measurement systems, and who use data derived from global measurement systems in order to manage networks or services or as input for regulatory decisions. ===================== Best, Vaibhav =================================== Vaibhav Bajpai www.vaibhavbajpai.com Room 91, Research I School of Engineering and Sciences Jacobs University Bremen, Germany ===================================

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Number of probes
by Marc Sanchez 11 May '16

11 May '16

I'm new in RIPE and I don't know it enough deeper. I need to check the state of several networks and I'm wondering how many probes should I need to measure a ping between two ASN. Could be enough using just one probe for each measurement? Sorry for the inconvenience. Sent via RIPE Forum -- https://www.ripe.net/participate/mail/forum

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probe congestion?
by Paul Vlaar 11 May '16

11 May '16

Hi all, while running a DNS UDM on a fixed set of (reused from a previous UDM) probes, I noticed the following. When I start 6 UDMs against the same set using the web UI, as a one-off measurement, starting "now", the RTTs for all of the measurements shoots up on all of the probes (500-1000+ ms). When I start the 6 tests individually, the RTTs are much lower, and close to what I'd expect them to be. It appears to me that when multiple UDMs are scheduled on the same probe, these should be run in serial, not parallel, in order to not run into congestion issues. Or am I simply expecting the wrong behaviour, and should I not schedule one-off measurements in parallel in the first place? ~paul

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SixXS issues
by Alison Wheeler 11 May '16

11 May '16

I received my second probe* yesterday (different ASNs) and it is connects via SixXS for IPv6 as the ISP isn't supplying native v6 (despite repeatedly asking when they will catch up on something around for twenty years!). It booted fine and the appear no issues with the IPv4 connectivity but the v6 is going up and down every few minutes (for around the same period.) Not finding anything relevant after searching the forum (nor on google) I'm trying to discover why this might be. My other machines are not experiencing any difficulty with v6 connectivity and the probe is connected to the same 16-port switch as everything else. Suggestions of what to investigate next very welcome! * https://atlas.ripe.net/probes/28800/ Sent via RIPE Forum -- https://www.ripe.net/participate/mail/forum

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New on RIPE Labs: Using RIPE Atlas to Debug Network Connectivity Problems
by Mirjam Kuehne 10 May '16

10 May '16

Dear colleagues, Please find this new article by Stéphane Bortzmeyer on RIPE Labs where he explains how he used RIPE Atlas probes, the official RIP Atlas API and custom scripts, to debug network issues: https://labs.ripe.net/Members/stephane_bortzmeyer/using-ripe-atlas-to-debug… Kind regards, Mirjam Kuehne RIPE NCC

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LatencyMON Widget Y axis in milliseconds
by Marat Khalili 10 May '16

10 May '16

I'm using LatencyMON <https://atlas.ripe.net/docs/tools-latencymon/> widget to monitor my network performance. It's very convenient. Unfortunately, it always loads with latency shown in %% (of what?), not in milliseconds, so I have to make one extra click in order to view actual milliseconds. Is there some hidden switch that would make milliseconds the default? Shouldn't it be initially default in the first place? -- With Best Regards, Marat Khalili

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ping measurements and high lts
by Clinton Work 10 May '16

10 May '16

When looking at the ping measurement json results I found some probes are reporting a very high lts (last time synchronized). Is it normal for very high lts values to be reported? These two anchors seem chronic: Probe 6161, max lts 65807 Probe 6132, max lts 23905 ================================= Clinton Work

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UDP Traceroute port?
by Laura M. Roberts 06 May '16

06 May '16

Hello, What port is used when a UDP traceroute is performed, please? Thank you, Laura

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