On 2026-09-08 08:34:37 +0100, Jonathan Dowland wrote: > That sounds like faulty applications, which could or should be fixed.
or the C library? > Vincent gave the example of wget, but I can't reproduce his problem; > I don't _think_ wget is faulty. Other applications are also affected by the issue, but in different and surprising ways: * mtr and traceroute are like wget: citron:~> mtr joooj.vinc17.net mtr: Packet type unsupported: Operation not supported but "mtr -4 joooj.vinc17.net" works. citron:~> traceroute joooj.vinc17.net traceroute to joooj.vinc17.net (2001:4b99:1:3:216:3eff:fe20:ac98), 30 hops max, 80 byte packets socket: Address family not supported by protocol but explicit IPv4 works: citron:~> traceroute -4 joooj.vinc17.net traceroute to joooj.vinc17.net (155.133.131.76), 30 hops max, 60 byte packets [...] 11 joooj.vinc17.net (155.133.131.76) 11.690 ms 11.666 ms 11.604 ms * ping: citron:~> ping joooj.vinc17.net ping: joooj.vinc17.net: Address family for hostname not supported However, the following is surprising: citron:~> ping -4 joooj.vinc17.net ping: joooj.vinc17.net: Address family for hostname not supported * ssh: citron:~> ssh joooj.vinc17.net ssh: Could not resolve hostname joooj.vinc17.net: Name or service not known citron:~> ssh -4 joooj.vinc17.net ssh: Could not resolve hostname joooj.vinc17.net: Name or service not known citron:~> ssh -6 joooj.vinc17.net socket: Address family not supported by protocol ssh: connect to host joooj.vinc17.net port 22: failure but "wget -4 joooj.vinc17.net" succeeds and "ssh -4 joooj.vinc17.net" still reproduces the same error. That's strange. * curl is fine: "curl joooj.vinc17.net" works like with the -4 option. The -6 option gives an unexpected error message: citron:~> curl -6 joooj.vinc17.net curl: (6) Could not resolve host: joooj.vinc17.net but perhaps this just means that it will not try to do an IPv6 resolution as IPv6 is unusable. > In his case, I'd want to see his routing table to confirm that IPv6 > was not accidentally enabled and configured. "ip -6 r" does not return anything and terminates with exit status 0, and "ip a" does not show any IPv6 address (even for lo). -- Vincent Lefèvre <[email protected]> - Web: <https://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / Pascaline project (LIP, ENS-Lyon)
