From owner-freebsd-questions@FreeBSD.ORG Tue Mar 13 18:48:42 2007 Return-Path: X-Original-To: questions@freebsd.org Delivered-To: freebsd-questions@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 301D016A400 for ; Tue, 13 Mar 2007 18:48:42 +0000 (UTC) (envelope-from pietro.cerutti@gmail.com) Received: from an-out-0708.google.com (an-out-0708.google.com [209.85.132.247]) by mx1.freebsd.org (Postfix) with ESMTP id D418F13C43E for ; Tue, 13 Mar 2007 18:48:41 +0000 (UTC) (envelope-from pietro.cerutti@gmail.com) Received: by an-out-0708.google.com with SMTP id c24so1837342ana for ; Tue, 13 Mar 2007 11:48:41 -0700 (PDT) DKIM-Signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=tUbo1BGt3EuQe/ocarXJFI1Tfw1usJI4/dlXaeLtuUf+yJkczBpgF19trKwTTqkJQn5iGUfvOFPdjBwYDcUFBEtWk0JHlhkC79kYbqadzEtfolGakdHJb1xpgk8/e8HF0HjFjchNqytDH0bUVYA94P3IharOU2imEHVyH+c+dRY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=AM33qW9ycT8Qjj3rNsU1XgBrrGDiCRQ2ZpRqXvuzNIsOL0l+NiHWZCJkv8Gau5zW7Mda7VvWGEZ6+rldajqbEa/BFPhv4wUU83LEA0yHOQ8wuedXV3FEtugVU5O88OBZPSe0Y2/SydHcaAWcLSgiJN4XEyHpwst8fehqP/U1fP4= Received: by 10.100.167.7 with SMTP id p7mr997940ane.1173811720855; Tue, 13 Mar 2007 11:48:40 -0700 (PDT) Received: by 10.100.111.5 with HTTP; Tue, 13 Mar 2007 11:48:40 -0700 (PDT) Message-ID: Date: Tue, 13 Mar 2007 19:48:40 +0100 From: "Pietro Cerutti" To: "Bill Moran" In-Reply-To: <20070313143555.ee27a265.wmoran@potentialtech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <64784.69.129.174.18.1173797935.squirrel@email.polands.org> <20070313111029.49bd1d14.wmoran@potentialtech.com> <53038.69.129.174.18.1173799128.squirrel@email.polands.org> <20070313143555.ee27a265.wmoran@potentialtech.com> Cc: questions@freebsd.org Subject: Re: UFS2 Snapshot limitiations X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 13 Mar 2007 18:48:42 -0000 On 3/13/07, Bill Moran wrote: > In response to "Pietro Cerutti" : > > > On 3/13/07, Doug Poland wrote: > > > > > > On Tue, March 13, 2007 10:10, Bill Moran wrote: > > > > In response to "Doug Poland" : > > > > > > > >> Hello, > > > >> > > > >> I seem to recall, but cannot find, the limitation on the number of > > > >> snapshots allowed on UFS2. Could someone point me in the right > > > >> direction please? > > > > > > > > The handbook has it: > > > > http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/snapshots.html > > > > > > > Thank you very much. > > > > > > > Sorry for joining the thread, but it's raised my curiosity: what's the > > reason for this limit? > > I'm not 100% sure, but I believe it's because snapshot information is stored > in the filesystem superblock, and that's all that can fit in the space > available in the superblock. This is the same thing that came to my mind, but in the handbook page I found: "Active snapshots are recorded in the superblock so they are persistent across unmount and remount operations along with system reboots." 1) what an "active" snapshot is? 2) is that limit limited (...) to active snapshots? Tnx > -- > Bill Moran > http://www.potentialtech.com > -- Pietro Cerutti - ASCII Ribbon Campaign - against HTML e-mail and proprietary attachments www.asciiribbon.org