From owner-freebsd-cloud@freebsd.org Sat Oct 28 20:20:56 2017 Return-Path: Delivered-To: freebsd-cloud@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id AB0B9E4C9A6 for ; Sat, 28 Oct 2017 20:20:56 +0000 (UTC) (envelope-from 0100015f64a4e4e0-ee3a9aef-7e84-4952-ba57-95d1d09c6a86-000000@amazonses.com) Received: from a8-26.smtp-out.amazonses.com (a8-26.smtp-out.amazonses.com [54.240.8.26]) (using TLSv1 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 70F647F7C9 for ; Sat, 28 Oct 2017 20:20:55 +0000 (UTC) (envelope-from 0100015f64a4e4e0-ee3a9aef-7e84-4952-ba57-95d1d09c6a86-000000@amazonses.com) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=ae7m2yrxjw65l2cqdpjxuucyrvy564tn; d=tarsnap.com; t=1509222049; h=Subject:To:References:Cc:From:Message-ID:Date:MIME-Version:In-Reply-To:Content-Type:Content-Transfer-Encoding; bh=pZdHIglDcIhQkhnQzW2RN1hH8hJ1U6cOCoFTQhWZhkw=; b=DBDiNJacmdROtIKbKMCATlnWASnuT7ifrd2wwcdimax8brchWPmfBgRbqF91DI/x HgQNPiKwaYCHAANyE/1ugdGHCZ+LzOI0QQ4+W2zw2A3SCEakfo3ACH1gLZ1pGFZS1+t Jf0liepW5aixb1sPA2Nd0xb09Iv6ZiKX4khLlDHM= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=224i4yxa5dv7c2xz3womw6peuasteono; d=amazonses.com; t=1509222049; h=Subject:To:References:Cc:From:Message-ID:Date:MIME-Version:In-Reply-To:Content-Type:Content-Transfer-Encoding:Feedback-ID; bh=pZdHIglDcIhQkhnQzW2RN1hH8hJ1U6cOCoFTQhWZhkw=; b=TALnkibL/w5VtMOPAtUr8LJ2dpVSfd04WkuLIZ4cIBmTYfIvrOJRR6qdgZg5N4US tu0AkDj1ycYgsRRG1IDaBNsSqL8ufL8Gd6Qqd4PhVetoyQxQLGr5n5HPvyuBduXl76n Qi5gTFmUsGKXRTawj94f2n55/GhdrynL0nHeVesk= Subject: Re: Shutdown causing reboot in EC2 To: Rafal Lukawiecki References: <0100015f63f81e60-c5bbcbd7-6423-4528-96d6-54e3f2cd345c-000000@email.amazonses.com> <3A5DB439-B89E-4B70-A984-433DF0209274@rafal.net> Cc: freebsd-cloud@freebsd.org From: Colin Percival Message-ID: <0100015f64a4e4e0-ee3a9aef-7e84-4952-ba57-95d1d09c6a86-000000@email.amazonses.com> Date: Sat, 28 Oct 2017 20:20:49 +0000 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <3A5DB439-B89E-4B70-A984-433DF0209274@rafal.net> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-SES-Outgoing: 2017.10.28-54.240.8.26 Feedback-ID: 1.us-east-1.Lv9FVjaNvvR5llaqfLoOVbo2VxOELl7cjN0AOyXnPlk=:AmazonSES X-BeenThere: freebsd-cloud@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "FreeBSD on cloud platforms \(EC2, GCE, Azure, etc.\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 28 Oct 2017 20:20:56 -0000 On 10/28/17 10:21, Rafal Lukawiecki wrote: >> Technically it's the FreeBSD project's image. :-) > > I realise that. I am glad to be using it via the Marketplace so that it enables you and FreeBSD RE to count the popularity of the OS on AWS. I understand you would not get the count otherwise. Just wanted to be clear. :-) >> I guess the obvious question here is "what does it mean for a virtual machine >> to be halted but not powered off”? > > I defer to you and to others who are more experienced than I to answer > this. The ‘shutdown -h’ behaviour with Amazon Linux and CentOS on AWS is to > power off. However, if reboot is what is supposed to happen in this case, I > will gladly adjust to that, although it feels a little odd. That wasn't so much a technical question as a philosophical question -- we've inherited shutdown actions from how hardware in the 1980s worked, and since 'shutdown -h' doesn't have any clear meaning in a VM I don't know that anyone gave it much thought. Certainly I never did. I suspect that the difference between Linux and FreeBSD here lies in how our underlying Xen code handles shutdown events... to be completely frank, I don't even know which code handles it under Xen HVM. But it's probably a bad idea to change it now, since some people have learned the existing behaviour. -- Colin Percival Security Officer Emeritus, FreeBSD | The power to serve Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid