From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" Newsgroups: gmane.emacs.bugs Subject: bug#58520: Persistent failure to DNS-lookup hostname Date: Fri, 03 Nov 2023 12:38:03 -0400 Message-ID: References: <875y2j9sm6.fsf@gmail.com> Reply-To: Stefan Monnier Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="27181"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Cc: 58520@debbugs.gnu.org, Paul Eggert To: Visuwesh Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Fri Nov 03 17:38:47 2023 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qyxC2-0006q1-UN for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 03 Nov 2023 17:38:47 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qyxBk-00011c-7m; Fri, 03 Nov 2023 12:38:28 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qyxBi-00010N-6a for bug-gnu-emacs@gnu.org; Fri, 03 Nov 2023 12:38:26 -0400 Original-Received: from debbugs.gnu.org ([2001:470:142:5::43]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1qyxBh-0005HI-Um for bug-gnu-emacs@gnu.org; Fri, 03 Nov 2023 12:38:25 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1qyxCH-0002Cc-Hv for bug-gnu-emacs@gnu.org; Fri, 03 Nov 2023 12:39:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Monnier Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 03 Nov 2023 16:39:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 58520 X-GNU-PR-Package: emacs Original-Received: via spool by 58520-submit@debbugs.gnu.org id=B58520.16990295318449 (code B ref 58520); Fri, 03 Nov 2023 16:39:01 +0000 Original-Received: (at 58520) by debbugs.gnu.org; 3 Nov 2023 16:38:51 +0000 Original-Received: from localhost ([127.0.0.1]:59649 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1qyxC7-0002CD-8X for submit@debbugs.gnu.org; Fri, 03 Nov 2023 12:38:51 -0400 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:51134) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1qyxC4-0002Bz-Ot for 58520@debbugs.gnu.org; Fri, 03 Nov 2023 12:38:49 -0400 Original-Received: from pmg3.iro.umontreal.ca (localhost [127.0.0.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id 2E16C442E72; Fri, 3 Nov 2023 12:38:07 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1699029484; bh=BMPMhy2j3mV64Zy1MFWhk3LScJ3vOJhTqEn5FAUH1QU=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=EFNbGYhZvXlKUVP5UGFHg+alGC9SOntvMIt4rMEAzGsS8oygcUOJnej9f2WfAM+PY WHhkzlkHNj++xed8DeSyLh5FI9uMgMtG2CEHt/1utTI1qMk0WXOrBczZQD1Z1J93Pd +KlubEtPPNzwjTLrM5nejNKnJqeM024BIj2HyQmyu+WcWhkEQY7wVw6Zg3oUAQ2VTH xMMVKLjv7xIdW+BLfcPWwyJ7nQfAAT2F212vdYBP2x+36x7qek7xF5QBfl53Mbr/b8 8EVu5APnC/Mq3dSbtq/GTpTl3NnNR9RoG3mNfRP5s+UAQF+sFyOB4mv9kUAxFZm22Y pXWsmMB7+n1Eg== Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id AE6C3442E6C; Fri, 3 Nov 2023 12:38:04 -0400 (EDT) Original-Received: from alfajor (unknown [23.233.149.155]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 900221202E0; Fri, 3 Nov 2023 12:38:04 -0400 (EDT) In-Reply-To: <875y2j9sm6.fsf@gmail.com> (Visuwesh's message of "Fri, 03 Nov 2023 13:27:21 +0530") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.bugs:273715 Archived-At: > FWIW, I experience this sometimes when I change from an Ethernet > connection to a WiFi connection (I cannot remember if the inverse is > true too). This change to another connection once I wake my laptop from > hibernation. During this change, /etc/resolv.conf definitely changes > because I use resolvconf to set connection-specific and > interface-specific DNS nameserver setting. [ I need to set the DNS > server manually for the Ethernet connection but I can use dhcp for the > Wifi one. ] Sounds like the exact same problem, indeed. If you ever come up with some further hints about what it needs to reproduce it (or even better: an actual recipe), I'd be happy to hear them. Currently it seems that hibernate/suspend might be related, tho I suspect it's a red herring. > The other super weird part is that eww _can_ open debbugs.gnu.org just > fine, but if I use Gnus to fetch the bug report it doesn't... Hmm... any chance that you're using some package which makes `eww` use some external tool instead of `url.el`? > I am not sure how long this failing Emacs instance will fail but if it > helps, I can try to do some debugging on my end as well. AFAICT once it happens it doesn't fix itself: the DNS server used by your Emacs process is "stuck" and doesn't pay attention to /etc/resolv.conf, so it "gets fixed" if you happen to be connected on a network where the DNS server that Emacs tries to contact is available. > I tried to use tcpdump but the manpage seems to suggest that there is > no way to filter network requests made by a particular process, and > I see too many junk requests to isolate the traffic that matters. I used a filter which only kept packets sent to a DNS port (port 53) and that was sufficient to see requests to the "wrong" DNS server (e.g. the one you use when your machine is connected via Ethernet, even though the machine is currently connected via wifi) and to confirm that those requests are correlated with the operation I perform in Emacs. Stefan