From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.burntcomma.com (mail2.burntcomma.com [217.169.27.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1A6CB23F27B for ; Mon, 30 Jun 2025 10:09:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.169.27.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751278164; cv=none; b=fmpHWrP18sGKC4Nk5VhiFsrHE9DKlJGrUX6LAjUWcRoJnnT0Ls469E9WPqfPTjwHpWL7yQbxtmjJ4stJ1yuOCexPC4mu4dhObaAcKyJy6A6b9i3M79rn/EOYGiwzpWl7Z2fyXBMc3hVfnlihbUHAv35eyH8QcIX1/6doIVXnfyo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751278164; c=relaxed/simple; bh=8bAv0bYUhy9TCGU8j0W9HbLS88I8oQawA6A+2LJTYes=; h=Message-ID:Date:Mime-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=tvDxD3p2y/vHIiZymcJz9eRSvhgsVyrCx5WavMPcRA3e6RX46OBKM3p34pnGxE4xOkvMT2ucuJ0afToln0amRjvS2NJiAlsauwmq/dEC/ngCn0EOu4HWy4lE0Xm2ISaswGcyXzbr/rEXCSg8+jee1p0bVW6C4R2LLV4oTPaBkq0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=harmstone.com; spf=pass smtp.mailfrom=harmstone.com; dkim=pass (1024-bit key) header.d=harmstone.com header.i=@harmstone.com header.b=rMX1j5R2; arc=none smtp.client-ip=217.169.27.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=harmstone.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=harmstone.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=harmstone.com header.i=@harmstone.com header.b="rMX1j5R2" Received: from [IPV6:2a02:8012:8cf0:0:ce28:aaff:fe0d:6db2] (beren.burntcomma.com [IPv6:2a02:8012:8cf0:0:ce28:aaff:fe0d:6db2]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "hellas", Issuer "burntcomma.com" (verified OK)) by mail.burntcomma.com (Postfix) with ESMTPS id 4C1452931A6; Mon, 30 Jun 2025 11:09:14 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=harmstone.com; s=mail; t=1751278154; bh=sU+98e1z47nHBSBif2vo5xoE2TPflnge2GQkvzXsAOk=; h=Date:Subject:To:References:From:In-Reply-To; b=rMX1j5R2skOhFhJMCWvSAWq6MnGp7pcuEa934BzP723l53dy1vWOhY8hIlU/pPT8c BoU6zYfGdZ6N8imJDQzH/guf0RAhkBoG616GuJJThGYWCgqSlr4wJXUaZx8IVRwtaf vC30vbFK64KmcJIvYSRgEQ2PRzGY+ZJXPgv7XirM= Message-ID: Date: Mon, 30 Jun 2025 11:09:14 +0100 Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Subject: Re: using snapshot for backup: best practise? To: linux-btrfs@vger.kernel.org, framstag@rus.uni-stuttgart.de References: <20250626114345.GA615977@tik.uni-stuttgart.de> Content-Language: en-US From: Mark Harmstone Autocrypt: addr=mark@harmstone.com; keydata= xsBNBFp/GMsBCACtFsuHZqHWpHtHuFkNZhMpiZMChyou4X8Ueur3XyF8KM2j6TKkZ5M/72qT EycEM0iU1TYVN/Rb39gBGtRclLFVY1bx4i+aUCzh/4naRxqHgzM2SeeLWHD0qva0gIwjvoRs FP333bWrFKPh5xUmmSXBtBCVqrW+LYX4404tDKUf5wUQ9bQd2ItFRM2mU/l6TUHVY2iMql6I s94Bz5/Zh4BVvs64CbgdyYyQuI4r2tk/Z9Z8M4IjEzQsjSOfArEmb4nj27R3GOauZTO2aKlM 8821rvBjcsMk6iE/NV4SPsfCZ1jvL2UC3CnWYshsGGnfd8m2v0aLFSHZlNd+vedQOTgnABEB AAHNI01hcmsgSGFybXN0b25lIDxtYXJrQGhhcm1zdG9uZS5jb20+wsCRBBMBCAA7AhsvBQsJ CAcCBhUICQoLAgQWAgMBAh4BAheAFiEEG2JgKYgV0WRwIJAqbKyhHeAWK+0FAmRQOkICGQEA CgkQbKyhHeAWK+22wgf/dBOJ0pHdkDi5fNmWynlxteBsy3VCo0qC25DQzGItL1vEY95EV4uX re3+6eVRBy9gCKHBdFWk/rtLWKceWVZ86XfTMHgy+ZnIUkrD3XZa3oIV6+bzHgQ15rXXckiE A5N+6JeY/7hAQpSh/nOqqkNMmRkHAZ1ZA/8KzQITe1AEULOn+DphERBFD5S/EURvC8jJ5hEr lQj8Tt5BvA57sLNBmQCE19+IGFmq36EWRCRJuH0RU05p/MXPTZB78UN/oGT69UAIJAEzUzVe sN3jiXuUWBDvZz701dubdq3dEdwyrCiP+dmlvQcxVQqbGnqrVARsGCyhueRLnN7SCY1s5OHK ls7ATQRafxjLAQgAvkcSlqYuzsqLwPzuzoMzIiAwfvEW3AnZxmZn9bQ+ashB9WnkAy2FZCiI /BPwiiUjqgloaVS2dIrVFAYbynqSbjqhki+uwMliz7/jEporTDmxx7VGzdbcKSCe6rkE/72o 6t7KG0r55cmWnkdOWQ965aRnRAFY7Zzd+WLqlzeoseYsNj36RMaqNR7aL7x+kDWnwbw+jgiX tgNBcnKtqmJc04z/sQTa+sUX53syht1Iv4wkATN1W+ZvQySxHNXK1r4NkcDA9ZyFA3NeeIE6 ejiO7RyC0llKXk78t0VQPdGS6HspVhYGJJt21c5vwSzIeZaneKULaxXGwzgYFTroHD9n+QAR AQABwsGsBBgBCAAgFiEEG2JgKYgV0WRwIJAqbKyhHeAWK+0FAlp/GMsCGy4BQAkQbKyhHeAW K+3AdCAEGQEIAB0WIQR6bEAu0hwk2Q9ibSlt5UHXRQtUiwUCWn8YywAKCRBt5UHXRQtUiwdE B/9OpyjmrshY40kwpmPwUfode2Azufd3QRdthnNPAY8Tv9erwsMS3sMh+M9EP+iYJh+AIRO7 fDN/u0AWIqZhHFzCndqZp8JRYULnspXSKPmVSVRIagylKew406XcAVFpEjloUtDhziBN7ykk srAMoLASaBHZpAfp8UAGDrr8Fx1on46rDxsWbh1K1h4LEmkkVooDELjsbN9jvxr8ym8Bkt54 FcpypTOd8jkt/lJRvnKXoL3rZ83HFiUFtp/ZkveZKi53ANUaqy5/U5v0Q0Ppz9ujcRA9I/V3 B66DKMg1UjiigJG6espeIPjXjw0n9BCa9jqGICyJTIZhnbEs1yEpsM87eUIH/0UFLv0b8IZe pL/3QfiFoYSqMEAwCVDFkCt4uUVFZczKTDXTFkwm7zflvRHdy5QyVFDWMyGnTN+Bq48Gwn1M uRT/Sg37LIjAUmKRJPDkVr/DQDbyL6rTvNbA3hTBu392v0CXFsvpgRNYaT8oz7DDBUUWj2Ny 6bZCBtwr/O+CwVVqWRzKDQgVo4t1xk2ts1F0R1uHHLsX7mIgfXBYdo/y4UgFBAJH5NYUcBR+ QQcOgUUZeF2MC9i0oUaHJOIuuN2q+m9eMpnJdxVKAUQcZxDDvNjZwZh+ejsgG4Ejd2XR/T0y XFoR/dLFIhf2zxRylN1xq27M9P2t1xfQFocuYToPsVk= In-Reply-To: <20250626114345.GA615977@tik.uni-stuttgart.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 26/06/2025 12.43 pm, Ulli Horlacher wrote: > > I am using fsfreeze when running a backup to ensure a consistent filesystem. > > While the backup is running writes to the filesystem are suspended and the > whole system is unresponsive, e.g. logins are not possible. > On certain errors the unfreeze will not happen and the system is locked > forever. > > Using snapshots seems a better idea for backups :-) > > But snapshots do not include subvolumes. Omar Sandoval had patches to add recursive snapshotting to btrfs-progs, but they never made it in, for reasons I can't remember. > For example the / filesystem has the subvolumes: > /home > /home/tux/test > /var/spool > > When I run the command: > > btrfs subvolume snapshot / /.snapshot/_ > > the snapshot will contain only the root subvolume. > > I have to manually add: > > rmdir /.snapshot/_/home > btrfs subvolume snapshot /home /.snapshot/_/home > rmdir /.snapshot/_/home/tux/test > btrfs subvolume snapshot /home/tux/test /.snapshot/_/home/tux/test > rmdir /.snapshot/_/var/spool > btrfs subvolume snapshot /var/spool /.snapshot/_/var/spool > > Then run the backup on /.snapshot/_ und afterwards: > > btrfs subvolume del /.snapshot/_/var/spool > btrfs subvolume del /.snapshot/_/home/tux/test > btrfs subvolume del /.snapshot/_/home > btrfs subvolume del /.snapshot/_ > > But this will work only for this special example! > And I have hundreds of systems to backup with different filesystem layout! > > Is there a best practise "Using snapshots for making backup"? > I need automatic detecting, creating and removing of nested snapshots. >