From owner-freebsd-doc@freebsd.org Wed Jun 28 19:01:26 2017 Return-Path: Delivered-To: freebsd-doc@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 D4F0FDA7CDE for ; Wed, 28 Jun 2017 19:01:26 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id C32358368F for ; Wed, 28 Jun 2017 19:01:26 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id v5SJ1QY2092254 for ; Wed, 28 Jun 2017 19:01:26 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-doc@FreeBSD.org Subject: [Bug 220343] The manual page for mpt should inform about disk size limitations of most/all supported controllers Date: Wed, 28 Jun 2017 19:01:26 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Documentation X-Bugzilla-Component: Documentation X-Bugzilla-Version: Latest X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: sebastian@rostwald.de X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-doc@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 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: 2.1.23 Precedence: list List-Id: Documentation project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 Jun 2017 19:01:26 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D220343 Bug ID: 220343 Summary: The manual page for mpt should inform about disk size limitations of most/all supported controllers Product: Documentation Version: Latest Hardware: Any OS: Any Status: New Severity: Affects Some People Priority: --- Component: Documentation Assignee: freebsd-doc@FreeBSD.org Reporter: sebastian@rostwald.de Most (if not all?) controllers supported by the mpt driver have firmware- and/or hardware-induced limitations on their supported disk/array/LUN size = -=20 mostly <2TB. As these limitations are well below typical sizes of modern ha= rd drives, it would be sensible to inform the user about these limitations in = the manual page. While most controllers truncate the usable/reported size to the supported s= ize, some might wrap around and cause serious data corruption. See for example t= he 3ware 7000/8000 series in this archived KB article: http://web.archive.org/web/20120326110817/http://kb.lsi.com:80/Knowledgebas= eArticle16481.aspx >From my own experiences, behaviour of many controllers with such limitations upon attaching bigger disks is best described as "undefined" - I've seen anything from not recognizing/reporting the disks, locking up at boot to se= vere data loss when reaching the supported size limit. Due to the possibility of data loss on controllers that wrap around address space, I suggest adding the information about these limitations and possible data loss within a WARNING section of the manual page. Draft/suggestion: ---- WARNING Most controllers supported by the mpt driver suffer from limitations on supported disk size (mostly <2TB). While *most* controllers will only trunc= ate usable disk size, others might behave unexpectedly and cause severe data lo= ss. Refer to the specifications of your chipset and firmware version for information about supported disk size. ---- --=20 Regards, Sebastian --=20 You are receiving this mail because: You are the assignee for the bug.=