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 TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 2C6F11382C5 for ; Tue, 22 Dec 2020 16:36:53 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 238ADE0B54; Tue, 22 Dec 2020 16:36:48 +0000 (UTC) Received: from smarthost01b.mail.zen.net.uk (smarthost01b.mail.zen.net.uk [212.23.1.3]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id BEC3DE0A4F for ; Tue, 22 Dec 2020 16:36:47 +0000 (UTC) Received: from [82.30.216.240] (helo=peak.localnet) by smarthost01b.mail.zen.net.uk with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1krkeU-0005C0-5A for gentoo-user@lists.gentoo.org; Tue, 22 Dec 2020 16:36:46 +0000 From: Peter Humphrey To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Big USB disks Date: Tue, 22 Dec 2020 16:36:45 +0000 Message-ID: <12671169.uLZWGnKmhe@peak> In-Reply-To: References: <5420897.DvuYhMxLoT@peak> 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 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Originating-smarthost01b-IP: [82.30.216.240] Feedback-ID: 82.30.216.240 X-Archives-Salt: b3146a76-d5ae-4398-bb0c-e89339df7fdd X-Archives-Hash: ba6bc2bb595674e5899c3b3708515a86 On Tuesday, 22 December 2020 15:32:27 GMT Rich Freeman wrote: > On Tue, Dec 22, 2020 at 7:58 AM Peter Humphrey wrote: > > Just a quickie - is there a way to enable a machine built on an MSDOS BIOS > > to recognise a partition on a 4TB external disk? I think I know the > > answer already, but just in case... > > I suspect most newer firmwares are fine with it (even in legacy mode), > and ancient ones would need a firmware update, so good luck with that. As I expected... > You might be able to mitigate the issue with a boot partition close to > the start of the disk. I'm honestly not sure if that works with > something like a USB hard drive. I'm not sure how old this system is > either. I wondered about that. I'm nervous, though, because this is my ultimate backup disk, and of course I don't want to endanger it. This disk is an external USB unit, not for booting from. Mr Google tells me the model was releases in 2007. I will have bought it within a year or so of that. > Back in the day MBR patches for large disks were a pretty common > thing. I'm not sure how much any modern OS depends on the firmware to > do disk IO once it is booted, and I'm not sure that most bootloaders > even need help from the firmware beyond maybe whatever goes in the > boot sector. This is why some GRUB modes require a secondary > partition near the start of the disk to handle certain > filesystems/etc. (Or at least used to - GRUB and EFI have gotten so > good that I don't pay much attention to that stuff on newer hardware > and with common filesystems, even including ZFS.) Thanks for the extra detail, Rich. -- Regards, Peter.