From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 31F5E158083 for ; Wed, 25 Sep 2024 14:26:51 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 15ABDE2B9A; Wed, 25 Sep 2024 14:26:45 +0000 (UTC) Received: from smtp.gentoo.org (woodpecker.gentoo.org [140.211.166.183]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id AFC6BE2A18 for ; Wed, 25 Sep 2024 14:26:44 +0000 (UTC) Message-ID: <0c9b42af-ad23-496d-a881-c0d0bb7e6e01@gentoo.org> Date: Wed, 25 Sep 2024 10:26:40 -0400 Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org X-Auto-Response-Suppress: DR, RN, NRN, OOF, AutoReply MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [gentoo-user] Wayland! Beware of! To: gentoo-user@lists.gentoo.org References: <65e5de50-e053-46ff-be61-52f472d95025@gentoo.org> <6af6d0dd-f081-4345-b574-ea6d6c9358bb@gentoo.org> Content-Language: en-US From: Eli Schwartz Autocrypt: addr=eschwartz@gentoo.org; keydata= xjMEZmeRNBYJKwYBBAHaRw8BAQdAYNZ7pUDWhx1i2f3p6L2ZLu4FcY18UoeGC04Gq/khqwfN I0VsaSBTY2h3YXJ0eiA8ZXNjaHdhcnR6QGdlbnRvby5vcmc+wpYEExYKAD4WIQTvUdMIsc4j CIi+DYTqQj6ToWND8QUCZoRL+gIbAwUJBKKGAAULCQgHAwUVCgkICwUWAgMBAAIeBQIXgAAK CRDqQj6ToWND8aB5AP9r4kB691nNtNwKkdRiOdl7/k6WYzokvHvDamXxRJ0I+gEAjZqR5V8y mfR3fy2Z+r2Joeqdt3CIv5IwPs64spBvigLOOARmZ5E0EgorBgEEAZdVAQUBAQdATT46Z06b 1X9xjXFCYFxmq/Tj3tSEKZInDWTpoHQp4l8DAQgHwn4EGBYKACYWIQTvUdMIsc4jCIi+DYTq Qj6ToWND8QUCZmeRNAIbDAUJBKKGAAAKCRDqQj6ToWND8a2RAP40KPfbfoiZAJW5boFmFJ3G TUBDJRh9CWHyaPqq2PN+0wD/R07oLzfnJUN209mzi9TuTuHjeZybysyqXSw4MAxkMAY= In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------PRd7X25QdPmPf8i90WcOC02R" X-Archives-Salt: ebf626de-f483-49b7-96df-1258b3264eb0 X-Archives-Hash: 76c5ba4b08e775f2479a7a8457afa03f This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --------------PRd7X25QdPmPf8i90WcOC02R Content-Type: multipart/mixed; boundary="------------7P3X1eE5d4z3w2ofqznKj0oC"; protected-headers="v1" From: Eli Schwartz To: gentoo-user@lists.gentoo.org Message-ID: <0c9b42af-ad23-496d-a881-c0d0bb7e6e01@gentoo.org> Subject: Re: [gentoo-user] Wayland! Beware of! References: <65e5de50-e053-46ff-be61-52f472d95025@gentoo.org> <6af6d0dd-f081-4345-b574-ea6d6c9358bb@gentoo.org> In-Reply-To: --------------7P3X1eE5d4z3w2ofqznKj0oC Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 9/25/24 6:00 AM, Walter Dnes wrote: > My system is actually very stable. In the shitstorm that erupted on > this list at "ipv6" enabling I did not see any mention of sysctl. In m= y > /etc/default/grub file I have... >=20 > GRUB_CMDLINE_LINUX_DEFAULT=3D"noexec=3Don net.ifnames=3D0 ipv6.disable=3D= 1" >=20 > With this setting is it guaranteed that a program compiled with "ipv6" > flag will not try IPV6 first and timeout before dropping down to IPV4? (Note that the sysctl dynamically disables ipv6 support so that you can manually toggle it after boot, e.g. for testing. The kernel command line option hard-disables it at boot time. Your choice which to use, I guess.)= If the kernel has disabled ipv6 there is no timeout because no attempt is made. If the kernel has enabled ipv6 then an attempt will be made and it may: - succeed, if your network has functioning ipv6 connectivity - fail instantly, if your network is correctly configured (you may not be in control of the network you use) - fail after a lengthy timeout after your network "valiantly" attempts to send your connection attempt into a black hole of doom As Arsen mentioned, RFC 8305 defines the "Happy Eyeballs" mechanism for trying both ipv4 and ipv6 at the same time, incurring the cost of slightly more traffic for the benefit of avoiding timeouts (since ipv4 will still succeed just as fast regardless of whether a parallel ipv6 is timing out, and as soon as ipv4 succeeds, the ipv6 timeout is ignored and made redundant). Not all software uses Happy Eyeballs. In particular, emerge --sync does not, because the python library that portage uses to check for updated PGP keys used when validating manifests, does not. This pained me tremendously since "emerge --sync" would literally hang forever, until I disabled ipv6 via the kernel. Note that since Aug 31, 2021, Gentoo's package for python has not supported USE=3Dipv6, but the sysctl works quite well. > How OS-specific is this? I "asked Mr. Google" and the NordVPN web > page recommended for Redhat based distros... It is specific to the linux kernel, that is all. You may replace "all" with the name of a machine-specific interface (as listed by "ip addr") to express settings that are specific to a given interface. Most people do not need that flexibility and simply want all interfaces to look the same. --=20 Eli Schwartz --------------7P3X1eE5d4z3w2ofqznKj0oC-- --------------PRd7X25QdPmPf8i90WcOC02R Content-Type: application/pgp-signature; name="OpenPGP_signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="OpenPGP_signature.asc" -----BEGIN PGP SIGNATURE----- wnsEABYIACMWIQTnFNnmK0TPZHnXm3qEp9ErcA0vVwUCZvQdoAUDAAAAAAAKCRCEp9ErcA0vV0T8 AQDqEjR+H1NSlB6U9q4ausVyL1cX56J/WIfPKajDIS2ZgwEAhRDLVFB/J55SRXYdP9Nn/TWeIJ/H qEuGy6P4XL7/Igk= =xeMp -----END PGP SIGNATURE----- --------------PRd7X25QdPmPf8i90WcOC02R--