Path: ...!feeds.phibee-telecom.net!2.eu.feeder.erje.net!feeder.erje.net!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: "Carlos E. R." Newsgroups: comp.os.linux.misc Subject: Re: Anybody Using IPv6? Date: Wed, 21 May 2025 03:46:45 +0200 Lines: 40 Message-ID: References: <100c46e$3c1el$1@news1.tnib.de> <100hcra$3nsq7$1@news1.tnib.de> <100hijb$25ta5$5@dont-email.me> <100hl34$3of0i$1@news1.tnib.de> <100i89e$19k3$1@news1.tnib.de> <100i92h$2a8rb$3@dont-email.me> <100ieve$1o3d$1@news1.tnib.de> <100irbu$2j9c$1@news1.tnib.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Trace: individual.net LBpHBlInqN6kDO4HDb9tQgvrwkwpLkJt50CoJxRfXdAFCA/XU1 Cancel-Lock: sha1:QiaX7DJZXr453UzgXBlJFaHp8gU= sha256:vr4KxVwpIFIoPGj83ssUfxvgVhOILAJcqkV7hV+fOHs= User-Agent: Mozilla Thunderbird Content-Language: en-CA, es-ANY In-Reply-To: <100irbu$2j9c$1@news1.tnib.de> Bytes: 2622 On 2025-05-20 23:14, Marc Haber wrote: > "Carlos E. R." wrote: >> On 2025-05-20 19:43, Marc Haber wrote: >>> What does the IPv6 routing table of the system in question say? >> >> I don't have a problem with the laptop currently. The problem was some >> years ago, on several computers. >> >> cer@Isengard:~> ip route >> default via 192.168.1.1 dev eth0 >> 192.168.0.0/16 dev eth0 proto kernel scope link src 192.168.1.16 >> cer@Isengard:~> > > That is not the IPv6 routing table. That is all there is. > >>>> So applications thought that IPv6 was available. >>> >>> Tries to use it, gets a host unreachable, SHOULD¹ try again with the >>> next IP address associated with the target hostname, which might >>> happen to be IPv4, tries to use it, connects successfully. >>> >>> Different behavior is a bug. >>> >>> ¹ in the RFC2119 sense >> >> The gai change makes things go faster, by not trying IPv6 first. > > On a slow machine, about a millisecond, yes. That matters in high > performance computing, where professionals do the administration. It > does absolutely not matter on a personal workstation that spends 99 % > of its CPU cycles waiting for keystrokes anyway. It is the network speed that matters, which is much slower. -- Cheers, Carlos E.R.