Towards an IPv6-only WLCG: More successes in reducing IPv4

Conference · Wed Jan 01 04:00:00 EST 2025 · EPJ Web Conf.

DOI:https://doi.org/10.1051/epjconf/202533701260· OSTI ID:3009883

Attebury, Garhan ^[1]; Babik, Marian ^[2]; Bly, Martin ^[3]; Buraglio, Nick ^[4]; Chown, Tim ^[5]; Christidis, Dimitrios ^[2]; Chudoba, Jiři ^[6]; DeMar, Phil ^[7]; Molina, José Flix ^[8]; Grigoras, Costin ^[2]; Hoeft, Bruno ^[9]; Ito, Hiro ^[10]; Kelsey, David ^[3]; Martelli, Edoardo ^[2]; McKee, Shawn ^[11]; Moreira, Carmen Misa ^[2]; Nandakumar, Raja ^[3]; Ohrenberg, Kars ^[12]; Prelz, Francesco ^[13]; Rand, Duncan ^[14] ; Sciabà, Andrea ^[2]; Skirvin, Tim ^[7]; Walker, Christopher ^[15]

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1. U. Nebraska, Lincoln
2. CERN
3. Rutherford Appleton Laboratory
4. LBNL, Berkeley
5. U. Bristol (main)
6. Prague, Inst. Phys.
7. Fermilab
8. Madrid, CIEMAT; Madrid, Escuela Tec. Sup. Ing. Ind.
9. KIT, Karlsruhe
10. Brookhaven Natl. Lab.
11. Michigan U.
12. DESY
13. INFN, Milan
14. Imperial Coll., London
15. Bristol U.

The Worldwide Large Hadron Collider Computing Grid (WLCG) community’s deployment of dual-stack IPv6/IPv4 on its worldwide storage infrastructure has been very successful. Dual-stack is not, however, a viable longterm solution; the HEPiX IPv6 Working Group has focused on studying where and why IPv4 is still being used, and how to flip such traffic to IPv6. The agreed end goal is to turn IPv4 off and run IPv6-only over the wide-area network to simplify both operations and security management.This paper reports our work since the CHEP2023 conference. Firstly, we present our campaign to deploy IPv6 on CPU services and Worker Nodes, with a deadline of end of June 2024. Then, the WLCG Data Challenge (DC24) performed in February 2024 was an excellent opportunity to observe the percentage of data transfers carried by IPv6. We observed the predominance of IPv6 in data transfers during DC24 and were able to understand yet more reasons for the use of IPv4 and areas for remedial action.The paper ends with the working group’s plans for moving WLCG to “IPv6- only”. One aspect of this is the possible automated use of IPv6-only clients configured with a customer-side translator, or CLAT, together with a deployment of NAT64 using what is often known as “IPv6-Mostly”, enabling IPv6-only sites to connect to non-WLCG IPv4-only services.

• Research Organization: Madrid, CIEMAT; Bristol U.; Madrid, Escuela Tec. Sup. Ing. Ind.; U. Bristol (main); Prague, Inst. Phys.; Brookhaven National Laboratory (BNL), Upton, NY (United States); Michigan U.; Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); KIT, Karlsruhe; CERN; Imperial Coll., London; LBNL, Berkeley; DESY; U. Nebraska, Lincoln; INFN, Milan; Rutherford Appleton Laboratory
• Sponsoring Organization: US Department of Energy
• DOE Contract Number: 89243024CSC000002
• OSTI ID: 3009883
• Report Number(s): FERMILAB-CONF-25-0938-CSAID-ITD; oai:inspirehep.net:3065542
• Resource Type: Conference paper
• Conference Information: Journal Name: EPJ Web Conf.
• Country of Publication: United States
• Language: English