From owner-freebsd-questions@freebsd.org Wed Sep 28 19:40:29 2016 Return-Path: Delivered-To: freebsd-questions@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 17A5AC009E6 for ; Wed, 28 Sep 2016 19:40:29 +0000 (UTC) (envelope-from dpchrist@holgerdanske.com) Received: from holgerdanske.com (holgerdanske.com [IPv6:2001:470:0:19b::b869:801b]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.he.net", Issuer "GeoTrust SSL CA - G4" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 092979C7 for ; Wed, 28 Sep 2016 19:40:29 +0000 (UTC) (envelope-from dpchrist@holgerdanske.com) Received: from ::ffff:99.100.19.101 ([99.100.19.101]) by holgerdanske.com for ; Wed, 28 Sep 2016 12:40:23 -0700 Subject: Re: FreeBSD-10.3-RELEASE-i386-memstick.img installer changes contents of USB flash drive? To: freebsd-questions@freebsd.org References: <56532342-f2d4-377d-605b-2e1b5bfb2160@holgerdanske.com> <028307a7-0771-6429-d72f-f85f9530f55d@citrin.ru> From: David Christensen X-Enigmail-Draft-Status: N1110 Message-ID: Date: Wed, 28 Sep 2016 12:40:23 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.2.0 MIME-Version: 1.0 In-Reply-To: <028307a7-0771-6429-d72f-f85f9530f55d@citrin.ru> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 Sep 2016 19:40:29 -0000 On 09/28/2016 09:58 AM, Anton Yuzhaninov wrote: > AFIK UFS superblock is updated every time filesystem is mounted, even > if FS is mounted in read-only mode (please correct me if I wrong). On 09/28/2016 11:34 AM, Ian Smith wrote: > We discerned recently that for 10.3, i386 memstick is GPT/EFI and > amd64 is still MBR/BSD. Since only the last sector differs, perhaps > something has updated the secondary GPT during the installation, > assuming that a GPT image should already include one - or at least, > the space for one? Thank you both for the replies. Either of the two mechanisms (filesystem superblock, spare GPT partition table) might explain the symptoms. > Possibly this doesn't matter at all, but it does seem 'untidy' at > best. Changing the last block of the image on a USB flash device violates the "Principle of Least Surprise" -- I expect the installation image to be "read only"; any change indicates a corrupt image and/or media failure. > I wonder if a hardware-write-protected GPT memstick would have > issues? The last USB flash memory stick I bought with an lock/unlock switch was a Memorex 128 MB in 2006. Since then, I've bought SanDisk, and they lack a switch. STFW there are a scarce few models with switches. Here's one that also has secure firmware: https://www.kanguru.com/storage-accessories/kanguru-flashtrust-secure-firmware.shtml How do I file a bug report against FreeBSD-10.3-RELEASE-i386-memstick.img? David