From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pobox.stuttgart.redhat.com (pobox.stuttgart.redhat.com [172.16.2.10]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id m3ULJqKx012036 for ; Wed, 30 Apr 2008 17:19:53 -0400 Received: from [10.32.4.47] (vpn-4-47.str.redhat.com [10.32.4.47]) by pobox.stuttgart.redhat.com (8.13.1/8.13.1) with ESMTP id m3ULJpex004171 for ; Wed, 30 Apr 2008 17:19:51 -0400 Message-ID: <4818E262.4070105@redhat.com> Date: Wed, 30 Apr 2008 23:19:30 +0200 From: Milan Broz MIME-Version: 1.0 Subject: Re: [linux-lvm] F7 will not boot after running backup w/snapshot References: <4817C2FD.1010909@verizon.net> <4817D97D.8060805@verizon.net> <4817ECAF.4020806@verizon.net> <48187B91.4060901@verizon.net> <1c748a490804300809s304f7fdfx55aeb0fd9c6cc7ab@mail.gmail.com> <4818AB1C.9030809@verizon.net> <4818BA5D.6070501@Media-Brokers.com> <4818D59A.8020906@verizon.net> In-Reply-To: <4818D59A.8020906@verizon.net> Content-Transfer-Encoding: 7bit Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii" To: LVM general discussion and development Gerry Reno wrote: > Charles, > Here's a snapshot ramdisk reference: > > http://linuxsoftware.co.nz/blog/2008/03/11/lvm-snapshot-with-no-free-diskspace > > The ramdisk has been working without problem. I tested it quite a bit > before putting it into production. But I don't know LVM internals so I > cannot say whether it could have had anything to do with the hang that > occurred. Please, do *not* use this configuration, it is very dangerous! Note that you extend Volume Group on you physical disk with another PV in volatile memory. Now imagine that your system crash (oh, wait, it happened already!) After reboot you have no ramdisk, and the Volume Group is incomplete (because you didn't removed PV on ramdisk). If there is only snapshot, you can recover it, if some operation placed here part of another volume, you will lose data. If there is root volume, system will not boot. Period. Milan -- mbroz@redhat.com