From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AAF71C433E6 for ; Tue, 2 Feb 2021 07:57:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A8A264EE9 for ; Tue, 2 Feb 2021 07:57:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231360AbhBBH5H (ORCPT ); Tue, 2 Feb 2021 02:57:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55986 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229621AbhBBH5F (ORCPT ); Tue, 2 Feb 2021 02:57:05 -0500 Received: from savella.carfax.org.uk (2001-ba8-1f1-f0e6-0-0-0-2.autov6rev.bitfolk.space [IPv6:2001:ba8:1f1:f0e6::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35185C061573 for ; Mon, 1 Feb 2021 23:56:25 -0800 (PST) Received: from hrm by savella.carfax.org.uk with local (Exim 4.92) (envelope-from ) id 1l6qVD-0002sP-2J; Tue, 02 Feb 2021 07:53:35 +0000 Date: Tue, 2 Feb 2021 07:53:34 +0000 From: Hugo Mills To: Christoph Anton Mitterer Cc: linux-btrfs@vger.kernel.org Subject: Re: is back and forth incremental send/receive supported/stable? Message-ID: <20210202075334.GP4090@savella.carfax.org.uk> Mail-Followup-To: Hugo Mills , Christoph Anton Mitterer , linux-btrfs@vger.kernel.org References: <157ed91bb66820d1fef89eb05d00e65c25607938.camel@scientia.net> <20210129192058.GN4090@savella.carfax.org.uk> <956e08b1aed7805f7ee387cc4994702c02b61560.camel@scientia.net> <20210201104609.GO4090@savella.carfax.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-GPG-Fingerprint: DD84 D558 9D81 DDEE 930D 2054 585E 1475 E2AB 1DE4 X-GPG-Key: E2AB1DE4 X-Parrot: It is no more. It has joined the choir invisible. X-IRC-Nicks: darksatanic darkersatanic darkling darkthing User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Mon, Feb 01, 2021 at 11:51:06PM +0100, Christoph Anton Mitterer wrote: > On Mon, 2021-02-01 at 10:46 +0000, Hugo Mills wrote: > >    It'll fail *obviously*. I'm not sure how graceful it is. :) > > Okay that doesn't sound like it was very trustworthy... :-/ > > Especially this from the manpage: > You must not specify clone sources unless you guarantee that these > snapshots are exactly in the same state on both sides—both for the > sender and the receiver. > > I mean what should the user ever be able to guarantee... respectively > what's meant with above? > > If the tools or any option combination thereof would allow one to > create corrupted send/received shapthots, then there's not much a user > can do. > If this sentence just means that the user mustn't have manually hacked > some UUIDs or so... well then I guess that's anyway clear and the > sentence is just confusing. It means that (a) the snapshots should exist, and (b) you shouldn't use the tools to make any of them read-write, make modifications, and make them read-only again. (and (c), as you say, don't modify the UUIDs). Hugo. > > but I guess it's not a priority for the devs > > Since it seems to be a valuable feature with probably little chances to > get it working in the foreseeable future, I've added it as a feature > request to the long term records ;-) > https://bugzilla.kernel.org/show_bug.cgi?id=211521 > > > > Cheers, > Chris. > -- Hugo Mills | hugo@... carfax.org.uk | __(_'> http://carfax.org.uk/ | Squeak! PGP: E2AB1DE4 |