From owner-freebsd-questions@FreeBSD.ORG Wed Jan 22 22:01:41 2014 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 09C2EF85 for ; Wed, 22 Jan 2014 22:01:41 +0000 (UTC) Received: from mail-ie0-x234.google.com (mail-ie0-x234.google.com [IPv6:2607:f8b0:4001:c03::234]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id CDD29187D for ; Wed, 22 Jan 2014 22:01:40 +0000 (UTC) Received: by mail-ie0-f180.google.com with SMTP id at1so204355iec.11 for ; Wed, 22 Jan 2014 14:01:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=SaePDGmP9SVq5ayRvatxuLtTWp4XbdM6TGWO2y51850=; b=NPccKbel5TZtDyHlfK5SfToBSzmhGRsXjsuzLSQV9fByhVEwK5kuvJVi73ZDryF494 BPmyuhBhC1kLHdNY7VvasAINRKcrHZVFtgMrZ/P/eaf2yF3wWgvwJoTZ3H7w1SnMPgah BhphJSpdu5pfBK4HyvVwNa9+Wlx+bxcmkksgX1ZpTRomE2qB9ki8OwaNBkJRwHUvzOj5 PRdYZ/yFznV5FaVaaDE5igU7QJjrdM/XPCt8vYyIk2rS8yw33OKrL6hYzC4uOrRnKaZn ZSTqlIqbkhUz4okfa0tJZbJ3XRnfgFy6SxdTcKAoaR4N4OzqTkX2k6RF6epqNNlnBxBz 39xg== MIME-Version: 1.0 X-Received: by 10.50.102.99 with SMTP id fn3mr25741867igb.5.1390428100287; Wed, 22 Jan 2014 14:01:40 -0800 (PST) Received: by 10.42.130.134 with HTTP; Wed, 22 Jan 2014 14:01:40 -0800 (PST) In-Reply-To: <20140122204828.GA6033@dan.emsphone.com> References: <20140122204828.GA6033@dan.emsphone.com> Date: Wed, 22 Jan 2014 14:01:40 -0800 Message-ID: Subject: Re: ZFS: pool vs FS From: Chris Stankevitz To: Dan Nelson Content-Type: text/plain; charset=ISO-8859-1 Cc: freebsd-questions@freebsd.org X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 Jan 2014 22:01:41 -0000 On Wed, Jan 22, 2014 at 12:48 PM, Dan Nelson wrote: > "zpool create" does create a filesystem Dan, Thank you. I suspected this was the case (the FreeBSD handbook certainly implies this). Now that we have that out of the way I can ask my real question: Can you identify the concept I am missing as evidenced by this failure: === # truncate -s 100m disk1 # truncate -s 100m disk2 # zpool create pool1 /root/disk1 # zpool create pool2 /root/disk2 So far so good... however, the next lines concern me. Some people seem to say "Wait, /pool1 is not a good filesystem to start using you need to uze 'zfs create' first". However your comment leads me to believe that /pool1 is okay to start using right away. # echo asdf > /pool1/file.txt # zfs snapshot pool1@123 Let's try to replicate: # zfs send pool1@123 | zfs recv pool2 cannot receive new filesystem stream: destination 'pool2' exists must specify -F to overwrite it Okay we have a problem. This is the heart of my misunderstanding. But I'll try to power through: # zfs send pool1@123 | zfs recv -F pool2 # zfs list -t snapshot NAME USED AVAIL REFER MOUNTPOINT pool1@123 18.5K - 31.5K - pool1@124 0 - 31.5K - pool2@123 0 - 31.5K - So far so good. And let's try another replication: # echo qwer > /pool1/file.txt # zfs snapshot pool1@124 # zfs send pool1@124 | zfs recv pool2 cannot receive new filesystem stream: destination 'pool2' exists must specify -F to overwrite it # zfs send pool1@124 | zfs recv -F pool2 cannot receive new filesystem stream: destination has snapshots (eg. pool2@123) must destroy them to overwrite it # echo Okay I do not understand what is happening. Thank you, Chris