From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp01.belwue.de ([129.143.71.86]:48554 "EHLO smtp01.belwue.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751716AbdHVSKK (ORCPT ); Tue, 22 Aug 2017 14:10:10 -0400 Received: from fex.rus.uni-stuttgart.de (fex.rus.uni-stuttgart.de [129.69.1.129]) by smtp01.belwue.de (Postfix) with SMTP id 753E58C22 for ; Tue, 22 Aug 2017 20:10:09 +0200 (MEST) Date: Tue, 22 Aug 2017 20:10:09 +0200 From: Ulli Horlacher To: linux-btrfs Subject: Re: netapp-alike snapshots? Message-ID: <20170822181009.GN14804@rus.uni-stuttgart.de> References: <20170822132208.GD14804@rus.uni-stuttgart.de> <20170822142451.GI14804@rus.uni-stuttgart.de> <20170822214531.44538589@natsu> <20170822165725.GL14804@rus.uni-stuttgart.de> <20170822223647.350ca27d@natsu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170822223647.350ca27d@natsu> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Tue 2017-08-22 (22:36), Roman Mamedov wrote: > > My users want the snapshots locally in a .snapshot subdirectory. > > Because Netapp do it this way - for at least 20 years and we have a > > multi-PB Netapp storage environment. > > Just a side note, you do know that only subvolumes can be snapshotted on Btrfs, > not any regular directory? And that snapshots are not recursive, i.e. if a > subvolume "contains" other subvolumes (hint: it really doesn't), snapshots of > the parent one will not include content of subvolumes below that in the tree. Yes, I know this. But thanks for your hints! (Other readers here may be not aware of this) > I don't know how Netapp does this I am only a Netapp/waffle user, so I know no internals. Netapp is not Linux based and definitly a lot older than btrfs. > from the way you describe that setup it feels like with Btrfs you're > still in for some bad surprises and a part of your expectations will not > be met. I will take care :-) > Do you plan to make each and every directory and subdirectory a subvolume No. My idea is to place a symlink in every subdirectory pointing to the snapshot directory. Not yet programmed... I was hoping someone already has implemented such a feature. -- Ullrich Horlacher Server und Virtualisierung Rechenzentrum TIK Universitaet Stuttgart E-Mail: horlacher@tik.uni-stuttgart.de Allmandring 30a Tel: ++49-711-68565868 70569 Stuttgart (Germany) WWW: http://www.tik.uni-stuttgart.de/ REF:<20170822223647.350ca27d@natsu>