From owner-freebsd-hackers@FreeBSD.ORG Mon Jan 23 18:21:15 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 08D46106564A for ; Mon, 23 Jan 2012 18:21:15 +0000 (UTC) (envelope-from Devin.Teske@fisglobal.com) Received: from mx1.fisglobal.com (mx1.fisglobal.com [199.200.24.190]) by mx1.freebsd.org (Postfix) with ESMTP id C569F8FC1E for ; Mon, 23 Jan 2012 18:21:14 +0000 (UTC) Received: from pps.filterd (ltcfislmsgpa03 [127.0.0.1]) by ltcfislmsgpa03.fnfis.com (8.14.4/8.14.4) with SMTP id q0NHfboR017838; Mon, 23 Jan 2012 12:21:09 -0600 Received: from smtp.fisglobal.com ([10.132.206.16]) by ltcfislmsgpa03.fnfis.com with ESMTP id 12hc5xr605-8 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT); Mon, 23 Jan 2012 12:21:09 -0600 Received: from dtwin (10.14.152.15) by smtp.fisglobal.com (10.132.206.16) with Microsoft SMTP Server (TLS) id 14.1.323.3; Mon, 23 Jan 2012 12:20:33 -0600 From: Devin Teske To: "'Ian Lepore'" References: <009501ccd9f9$cad088d0$60719a70$@fisglobal.com> <1327342618.69022.83.camel@revolution.hippie.lan> In-Reply-To: <1327342618.69022.83.camel@revolution.hippie.lan> Date: Mon, 23 Jan 2012 10:20:35 -0800 Message-ID: <009c01ccd9fb$b40cfaf0$1c26f0d0$@fisglobal.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQI49xgFl+9M2RezXQleHqiUG5VWrwH+7YvilTIRdFA= Content-Language: en-us X-Originating-IP: [10.14.152.15] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.6.7361, 1.0.211, 0.0.0000 definitions=2012-01-23_03:2012-01-22, 2012-01-23, 1970-01-01 signatures=0 Cc: freebsd-hackers@freebsd.org Subject: RE: Parallels v4 regression (aka ada(4) oddity) in RELENG_9 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 23 Jan 2012 18:21:15 -0000 > -----Original Message----- > From: Ian Lepore [mailto:freebsd@damnhippie.dyndns.org] > Sent: Monday, January 23, 2012 10:17 AM > To: Devin Teske > Cc: freebsd-hackers@freebsd.org > Subject: Re: Parallels v4 regression (aka ada(4) oddity) in RELENG_9 > > On Mon, 2012-01-23 at 10:06 -0800, Devin Teske wrote: > > I have a Parallels virtual machine and it runs FreeBSD 4 through 8 just > > swimmingly. > > > > However, in RELENG_9 I notice something different. My once "ad0" is now > showing > > up as "ada0". However, something even stranger is that devfs is providing both > > ad0 family devices AND ada0 family devices. > > > > What's worse is that I can't seem to partition the disk with MBR+disklabel > > scheme. > > > > My procedure goes something like this: > > > > 1. Boot from RELENG_9 LiveCD > > 2. Execute: sysctl -n kern.disks > > 3. Notice two items: cd0 ada0 > > 4. Look in /dev > > 5. Notice several items: ad0 ad0p1 ad0p2 ad0p3 ada0 ada0p1 ada0p2 ada0p3 > > 6. Wipe partition table by executing: dd if=/dev/zero of=/dev/ada0 bs=512k > > count=256 > > 7. Look in /dev > > 8. Notice less items now: ad0 ada0 > > 9. Execute: sysctl -n kern.disks > > 10. Notice nothing changed: cd0 ada0 > > 11. Write out standard "whole disk" MBR "slice" > > 12. Look in /dev > > 13. Notice that nothing changed: ad0 ada0 > > NOTE: Where is ad0s1 or ada0s1? > > 14. Use fdisk to make sure everything was written successfully > > 15. Notice everything looks good (slice 1 is of type FreeBSD, slice 2, 3, and 4 > > are unused) > > 16. Reboot > > 17. Boot back into RELENG_9 LiveCD > > 18. Look in /dev > > 19. Notice that the old devices are back!: ad0 ad0p1 ad0p2 ad0p3 ada0 ada0p1 > > ada0p2 ada0p3 > > 20. Use fstab to look at MBR partition table > > 21. Notice that things look good (with respect to fdisk'ing): slice 1 is > > FreeBSD, 2, 3, and 4 are still unused > > 22. Notice /dev still doesn't have ad0s1 or ada0s1 > > 23. Use gpart to look at ada0 > > 24. Notice "GPT [CORRUPT]" > > > > ... > > > > OK!?!? > > > > ... > > > > Use same exact RELENG_9 LiveCD on either a physical machine or VMware > Virtual > > machine. > > > > SUCCESS!! > > > > Go back to Parallels 4 > > > > FAILURE!! > > > > Go back to RELENG_8 LiveCD with Parallels 4 > > > > SUCCESS!! > > > > What's going on here? I think ada(4) is my problem. Can someone please > provide > > feedback? Willing to dig further and provide any/all feedback to help fix this > > regression. > > I've experienced the part of that scenario where changing a drive from > gpt to mbr scheme results in all the gpt partitions reappearing after a > reboot. I concluded (but didn't take time to be absolutely certain) > that during boot the geom layer was seeing the backup gpt partition info > at the end of the disk Ah! There's a backup partition at the END of the disk! /me is new to GPT > and concluding that it needed to ignore the mbr > and use the backup gpt info instead. Once I quit using dd and similar > tools and consistantly used "gpart destroy" to wipe out the gpt before > changing to mbr, it stopped happening. > Ah! Thanks Ian (and Garrett in another reply)! I'll give "gpart destroy a try" -- Devin _____________ The information contained in this message is proprietary and/or confidential. 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