From owner-freebsd-doc@freebsd.org Wed Jul 15 14:27:28 2020 Return-Path: Delivered-To: freebsd-doc@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 352573678EA for ; Wed, 15 Jul 2020 14:27:28 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.nyi.freebsd.org (unknown [127.0.1.3]) by mx1.freebsd.org (Postfix) with ESMTP id 4B6KTq1Qgqz47mM for ; Wed, 15 Jul 2020 14:27:27 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id 86175367B03; Wed, 15 Jul 2020 14:27:26 +0000 (UTC) Delivered-To: doc@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 76C02367947 for ; Wed, 15 Jul 2020 14:27:26 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4B6KTn6ZYbz480y for ; Wed, 15 Jul 2020 14:27:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 78CF418A0C for ; Wed, 15 Jul 2020 14:27:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 06FERPt9082753 for ; Wed, 15 Jul 2020 14:27:25 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 06FERPmx082752 for doc@FreeBSD.org; Wed, 15 Jul 2020 14:27:25 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: doc@FreeBSD.org Subject: [Bug 248002] ping(8): TTL DETAILS update Date: Wed, 15 Jul 2020 14:27:25 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Documentation X-Bugzilla-Component: Manual Pages X-Bugzilla-Version: Latest X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: jlduran@gmail.com X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter cc Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-doc@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: Documentation project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Jul 2020 14:27:28 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D248002 Bug ID: 248002 Summary: ping(8): TTL DETAILS update Product: Documentation Version: Latest Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: Manual Pages Assignee: bugs@FreeBSD.org Reporter: jlduran@gmail.com CC: doc@FreeBSD.org, net@FreeBSD.org Reading ping(8), section "TTL DETAILS", I have seen a number of inconsistencies regarding this value in FreeBSD. This section of the man p= age has not been updated to reflect the current state. For instance: > Not change it; this is what BSD systems did before the 4.3BSD-Tahoe relea= se. > In this case the TTL value in the received packet will be 255 minus the > number of routers in the round-trip path. This paragraph implies that FreeBSD is still using 255 as its default TTL, it should be updated to reflect the current value (64) [1], perhaps: Not change it; this is what BSD systems did before the 4.3BSD-Tahoe release. In this case the TTL value in the received packet will be 64 minus the numb= er of routers in the round-trip path. Other paragraphs could also be updated, for example: > The TCP/IP specification recommends setting the TTL field for IP packets = to > 64, but many systems use smaller values (4.3BSD uses 30, 4.2BSD used 15). The TCP/IP specification recommends setting the TTL field for IP packets to 64, FreeBSD uses this value... The DESCRIPTION mentions that the sysctl net.inet.ip.ttl is used, but it does not say that this value is 64 by default. Maybe also include some current OSs? I have compiled a quick list that can = be easily verified pinging the hosts inside the brackets, this should give you the TTL (plus the number of hops): Windows: 128 [live.com] BSDs (NetBSD and OpenBSD): 255 [netbsd.org, openbsd.org] Linux: 64 [linux.org] FreeBSD, macOS: 64 > Set it to 255; this is what current BSD systems do. In this case the TTL > value in the received packet will be 255 minus the number of routers in t= he > path from the remote system to the pinging host. Set it to 255; this is what some BSD systems do... Some current BSD systems do use 255 (at least NetBSD and OpenBSD); however, FreeBSD uses the IANA-recommended value of 64 [2]. References: [1]=20 https://github.com/freebsd/freebsd/blob/3f4da6d3e7a2a8cc34a94938bd1c4f80c8d= 1d449/sys/netinet/ip.h#L212 [2]=20 https://www.iana.org/assignments/ip-parameters/ip-parameters.xhtml#ip-param= eters-2 --=20 You are receiving this mail because: You are on the CC list for the bug.=