From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <f.weber@proxmox.com> Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id EE3B692075 for <pve-devel@lists.proxmox.com>; Wed, 31 Jan 2024 16:07:52 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id CF7513D0B8 for <pve-devel@lists.proxmox.com>; Wed, 31 Jan 2024 16:07:52 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for <pve-devel@lists.proxmox.com>; Wed, 31 Jan 2024 16:07:51 +0100 (CET) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 246694543C for <pve-devel@lists.proxmox.com>; Wed, 31 Jan 2024 16:07:51 +0100 (CET) Message-ID: <80c410ca-3615-45cc-9801-f1e2d14cab78@proxmox.com> Date: Wed, 31 Jan 2024 16:07:50 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: en-US To: Fiona Ebner <f.ebner@proxmox.com>, Proxmox VE development discussion <pve-devel@lists.proxmox.com> References: <20240111150332.733635-1-f.weber@proxmox.com> <c447ba98-649a-40cd-809e-4e120faa1b72@proxmox.com> From: Friedrich Weber <f.weber@proxmox.com> In-Reply-To: <c447ba98-649a-40cd-809e-4e120faa1b72@proxmox.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL -0.087 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record T_SCC_BODY_TEXT_LINE -0.01 - URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [proxmox.com] Subject: Re: [pve-devel] [PATCH storage 0/2] fix #4997: lvm: avoid autoactivating (new) LVs after boot X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion <pve-devel.lists.proxmox.com> List-Unsubscribe: <https://lists.proxmox.com/cgi-bin/mailman/options/pve-devel>, <mailto:pve-devel-request@lists.proxmox.com?subject=unsubscribe> List-Archive: <http://lists.proxmox.com/pipermail/pve-devel/> List-Post: <mailto:pve-devel@lists.proxmox.com> List-Help: <mailto:pve-devel-request@lists.proxmox.com?subject=help> List-Subscribe: <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>, <mailto:pve-devel-request@lists.proxmox.com?subject=subscribe> X-List-Received-Date: Wed, 31 Jan 2024 15:07:53 -0000 Thanks for the review! On 26/01/2024 12:14, Fiona Ebner wrote: >> Some points to discuss: >> >> * Fabian and I discussed whether it may be better to pass `-K` and set the >> "activation skip" flag only for LVs on a *shared* LVM storage. But this may >> cause issues for users that incorrectly mark an LVM storage as shared, create a >> bunch of LVs (with "activation skip" flag), then unset the "shared" flag, and >> won't be able to activate LVs afterwards (`lvchange -ay` without `-K` on an LV >> with "activation skip" is a noop). What do you think? >> > > Is there a way to prevent auto-activation on boot for LVs on a shared > (PVE-managed) LVM storage? Also a breaking change, because users might > have other LVs on the same storage, but would avoid the need for the > flag. Not against the current approach, just wondering. One can also disable autoactivation for a whole VG (i.e., all LVs of that VG): vgchange --setautoactivation n VG At least in my tests, after setting this no LV in that VG is active after boot, so this might also solve the problem. I suppose setting this automatically for existing VGs would be too dangerous (as users might have other LVs in that VGs). But our LVM storage plugin *could* set this when creating a new shared VG [1]? Not sure which option is better, though. > Guardrails against issues caused by misconfiguration always warrant a > cost-benefits analysis. What is the cost for also setting the flag for > LVs on non-shared LVM storages? Or logic needs to be correct either way ;) AFAICT, setting this LV flag on non-shared LVM storages doesn't have negative side-effects. I don't think we rely on autoactivation anywhere. We'd need to take care of passing `-K` for all our `lvchange -ay` calls, but AFAICT, `lvchange` calls are only done in the LVM/LvmThin plugins in pve-storage. [1] https://git.proxmox.com/?p=pve-storage.git;a=blob;f=src/PVE/Storage/LVMPlugin.pm;h=4b951e7a;hb=8289057e#l94