From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from wecheer.com ([54.200.0.65]:57915 "EHLO wecheer.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751864AbaBCWx2 (ORCPT ); Mon, 3 Feb 2014 17:53:28 -0500 Received: from localhost (localhost [127.0.0.1]) by wecheer.com (Postfix) with ESMTP id 6674B45B90 for ; Mon, 3 Feb 2014 22:53:35 +0000 (UTC) Received: from wecheer.com ([127.0.0.1]) by localhost (ip-172-31-45-254.us-west-2.compute.internal [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id lXna732zQafA for ; Mon, 3 Feb 2014 22:53:32 +0000 (UTC) Received: from [10.10.22.177] (unknown [207.194.255.202]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: m) by wecheer.com (Postfix) with ESMTPSA id 6E39C45B8D for ; Mon, 3 Feb 2014 22:53:32 +0000 (UTC) Message-ID: <52F01DE1.7030102@matthewlai.ca> Date: Mon, 03 Feb 2014 14:53:21 -0800 From: Matthew Lai MIME-Version: 1.0 To: linux-btrfs@vger.kernel.org Subject: Re: Receive on same subvolume References: <52E9721D.6000908@matthewlai.ca> <4D0416BE-42D6-4458-9519-9836CC979005@colorremedies.com> <52EFDDA6.2060907@matthewlai.ca> <8BD36B4A-F9AF-40C6-81B8-85FD14CD5EA1@colorremedies.com> In-Reply-To: <8BD36B4A-F9AF-40C6-81B8-85FD14CD5EA1@colorremedies.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 03/02/2014 11:26 AM, Chris Murphy wrote: > On Feb 3, 2014, at 11:19 AM, Matthew Lai wrote: > >> Thanks. I should clarify what I'm trying to do. >> >> I'm trying to use btrfs send for backup, without having another btrfs volume. >> >> So the initial backup is a complete send, piped to Amazon Glacier (so my machine never has the whole file, and doesn't have space for one). > OK so you've use btrfs send piped to Glacier which creates a *file*, I'll call it "initial", not a navigable directory of files? Right? That is correct. >> It looks like the problem now is the sent file can't be applied to the original volume (for restore). > I'm counting two sent files: initial, increment1. I'm not sure which one you're applying. If you have the exact same read-only snapshot that the btrfs send file "initial" is based on, then you'd apply the increment1 to that read-only snapshot which will cause a new read-only snapshot to be created with the incremental data applied to it. The error you're getting sounds like the parent read-only snapshot isn't available? > That is also correct. There are 2 sent files. I am trying to apply increment1, on a snapshot of the parent (that was used to create increment1). I added -vv. Here is the test script for reproducing this entire setup. ----------------------------------------------------------------------- #!/bin/sh btrfs subvolume create data btrfs subvolume snapshot -r data first_backup touch data/a btrfs subvolume snapshot -r data second_backup btrfs send -p first_backup second_backup > increment btrfs subvolume snapshot first_backup first_backup_rw btrfs receive -vv first_backup_rw < increment ----------------------------------------------------------------------- Output: ----------------------------------------------------------------------- Create subvolume './data' Create a readonly snapshot of 'data' in './first_backup' Create a readonly snapshot of 'data' in './second_backup' At subvol second_backup Create a snapshot of 'first_backup' in './first_backup_rw' At snapshot second_backup receiving snapshot second_backup uuid=e6159a2a-3430-344a-a23d-b9bb83851a63, ctransid=28 parent_uuid=20c4ff66-a9ec-fc44-93c6-2c12637e95e6, parent_ctransid=26 ERROR: could not find parent subvolume ----------------------------------------------------------------------- I would think applying the "patch" to first_backup_rw should succeed, because it's exactly the same as first_backup, which is the parent for the send, but it doesn't. Thanks Matthew