August 2025 - NANOG - lists.nanog.org

Recommended DNS server for a medium 20-30k users isp
by DurgaPrasad - DatasoftComnet 21 Aug '25

21 Aug '25

Hello all, Do you have any recommendations for recursive DNS servers for a medium sized (20-30k users) ISP. We have used powerdns and unbound but sometimes find the caching times a bit on upper side. Any suggestions between these two or anything new? Also need points on how much we tune the settings pros and cons if any. Thank you /DP

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Re: : Can a prefix be never routed on Internet but used only for source address in IP packets?
by Jakob Heitz (jheitz) 20 Aug '25

20 Aug '25

ICMP packets from internal devices. Example “unreachable”. Kind Regards, Jakob ---------------------------- Question: Can a prefix be never routed on the Internet but used only one-way for source address in IP packets? That is. a user owns an IP prefix. They never advertise a route to it in BGP on the Internet. But they use the prefix solely for source address in IP traffic from a source to a destination (sink). In this set up, the destination server obviously cannot/doesn't return any acknowledgements etc. to the source. Anyone aware if there is any such known application in use on the Internet - even if it is rare? Thanks. Sriram

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Can a prefix be never routed on Internet but used only for source address in IP packets?
by Sriram, Kotikalapudi (Fed) 20 Aug '25

20 Aug '25

Question: Can a prefix be never routed on the Internet but used only one-way for source address in IP packets? That is. a user owns an IP prefix. They never advertise a route to it in BGP on the Internet. But they use the prefix solely for source address in IP traffic from a source to a destination (sink). In this set up, the destination server obviously cannot/doesn't return any acknowledgements etc. to the source. Anyone aware if there is any such known application in use on the Internet - even if it is rare? Thanks. Sriram

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Internet Visualization Exhibit (IVE) at SIGCOMM 2025
by Loqman Salamatian 19 Aug '25

19 Aug '25

Paul Barford (University of Wisconsin–Madison) and I (Columbia University) are organizing the Internet Visualization Exhibition (IVE) as a special, non-paper session at SIGCOMM 2025 on September 11. The goal is to showcase creative and insightful visualizations of Internet-scale systems — from connectivity maps and temporal changes to AS-level graphs and other innovative ways of making the Internet more understandable. If you’ve created visualizations that reveal patterns, highlight anomalies, or explain complex behaviors in the Internet, we would love to see them and showcase them. We’re looking for: Static images, animations, or interactive demos Visuals that reveal structure, highlight anomalies, or explain complex behaviors Work that’s compelling, bold, or just visually satisfying Submissions are lightweight: just a visual and a short description. There’s no formal review process. Important: You don’t need to attend SIGCOMM to take part. While presenting in person is a great way to connect with others and share your work, the exhibition is open to submissions from anyone, anywhere. Whether you’re a researcher, network operator, data-viz enthusiast, or artist working with Internet data or infrastructure, we’d love to see what you’ve been visualizing! 📄 More details: https://burdantes.github.io/ive/ 📩 Questions? Reach out to me. And please share with anyone who might be interested! Loqman Salamatian

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Re: Can a prefix be never routed on Internet but used only for source address in IP packets?
by Jonathan Kalbfeld 19 Aug '25

19 Aug '25

This happens unintentionally quite a bit with misconfigured NAT. You will see RFC 1918 source addresses in packets from time to time. I can't speak to the application or value of this, but I have seen this and done it accidentally on one occasion. Jonathan Kalbfeld office: +1 310 317 7933 fax: +1 310 317 7901 home: +1 310 317 7909 mobile: +1 310 227 1662 ThoughtWave Technologies, Inc. Studio City, CA 91604 https://thoughtwave.com View our network at https://bgp.he.net/AS54380 +1 844 42-LINUX > > On Aug 19, 2025 at 9:34 AM, Sriram, Kotikalapudi (Fed) via NANOG <nanog(a)lists.nanog.org> wrote: > > > Question: Can a prefix be never routed on the Internet but used only one-way for source address in IP packets? > > That is. a user owns an IP prefix. They never advertise a route to it in BGP on the Internet. But they use the prefix solely for source address in IP traffic from a source to a destination (sink). In this set up, the destination server obviously cannot/doesn't return any acknowledgements etc. to the source. Anyone aware if there is any such known application in use on the Internet - even if it is rare? Thanks. > > Sriram > _______________________________________________ > NANOG mailing list > https://lists.nanog.org/archives/list/nanog@lists.nanog.org/message/MSEGDFS… >

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Available: 2x Juniper MX304 (Fully Loaded, NIB, Texas)
by John Parsons 19 Aug '25

19 Aug '25

Hi all, We have two Juniper MX304 Chassis, fully loaded with line cards and optics, new-in-box, available immediately in Texas. * Condition: factory-sealed, never deployed * Configuration: [insert line cards + optics if you have them] * Location: Texas, can ship same day * Ideal for edge/core refresh, metro aggregation, or 5G backhaul If anyone has an immediate need, please reach out off-list for config details and terms. [A picture containing text, font, graphics, logo Description automatically generated]<http://www.withmender.com/> John Parsons Sourcing Manager Mobile 970-903-9212 Web www.withmender.com<http://www.withmender.com/> Email johnp(a)withmender.com<mailto:johnp@withmender.com> 1301 Texas Star Parkway, Euless, TX 76040 [A picture containing symbol, logo, text, font Description automatically generated]<https://orioncertification.com/>[A picture containing graphics, logo, font, graphic design Description automatically generated]<https://sustainableelectronics.org/welcome-to-r2v3/> [A blue square with white letters Description automatically generated with medium confidence] <https://www.linkedin.com/company/withmender/>

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route-server.ip.att.net - needs help?
by Aaron Gould 19 Aug '25

19 Aug '25

I can ping it, but can't telnet/ssh to it. route-server.ip.att.net -- -Aaron

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Contact Zoom Communications AS30103
by Fran 18 Aug '25

18 Aug '25

Hello, anyone from zoom AS30103 on this list. Peeringdb contacts are not responding. :/ Please contact me off list. Thanks a lot! Fran

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NANOG Mailman 3.0 server location migration
by Valerie Wittkop 16 Aug '25

16 Aug '25

Hello NANOGers, During the evening on Friday August 15, 2025 between 8 pm to 12 am EDT (Saturday August 16, 0000 to 0400 UTC), NANOG will perform a migration of our Mailman 3.0 server. During this time, all mailing lists will be unavailable, including the ability to make changes to your subscription options. We expect this migration to be completed in three hours time or backed out. Detailed notes: NANOG will be migrating the hosted location of Mailman 3.0 during this time. This migration will include new IP addresses. Please note the new IP addresses will be 104.197.34.15 and 2600:1900:4001:5d2:0:0:0:0 Sincerely, NANOG Staff ------------------------- *Valerie Wittkop* Program Directorvwittkop(a)nanog.org | +1 734-730-0225 <+17347300225> (mobile) | www.nanog.org NANOG | 305 E. Eisenhower Pkwy, Suite 100 | Ann Arbor, MI 48108, USA ASN 19230

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Unitas
by Alex 15 Aug '25

15 Aug '25

Hello. Was there a Unitas network outage for ~15 minutes today?

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