From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) by lore.proxmox.com (Postfix) with ESMTPS id 0A5DF1FF144 for ; Tue, 10 Mar 2026 15:11:41 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 996371F8AF; Tue, 10 Mar 2026 15:11:33 +0100 (CET) Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Tue, 10 Mar 2026 15:11:27 +0100 Message-Id: From: "Daniel Kral" To: "Fiona Ebner" , "Proxmox VE development discussion" Subject: Re: [pve-devel] [PATCH qemu-server] migration: prohibit renaming cloud-init drive X-Mailer: aerc 0.21.0-38-g7088c3642f2c-dirty References: <20251201135345.125993-1-f.ebner@proxmox.com> <4f619b8f-b0d3-4163-af25-e53272aa7bea@proxmox.com> <0f6d46a7-ee96-47c6-8c60-ce7348166d4a@proxmox.com> In-Reply-To: <0f6d46a7-ee96-47c6-8c60-ce7348166d4a@proxmox.com> X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1773151854260 X-SPAM-LEVEL: Spam detection results: 0 AWL -1.030 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 RCVD_IN_VALIDITY_CERTIFIED_BLOCKED 0.408 ADMINISTRATOR NOTICE: The query to Validity was blocked. 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SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Message-ID-Hash: A7XFZY3S4HSGHDE5ER4QFIIPI6WYXFWB X-Message-ID-Hash: A7XFZY3S4HSGHDE5ER4QFIIPI6WYXFWB X-MailFrom: d.kral@proxmox.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.10 Precedence: list List-Id: Proxmox VE development discussion List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Tue Mar 10, 2026 at 1:38 PM CET, Fiona Ebner wrote: > Am 10.03.26 um 1:30 PM schrieb Fiona Ebner: >> Am 10.03.26 um 1:22 PM schrieb Daniel Kral: >>> On Mon Dec 1, 2025 at 2:51 PM CET, Fiona Ebner wrote: >>>> Usually, disks are allowed to be renamed during migration if there is >>>> a naming conflict caused by a left-over disk on the target. However, >>>> the type of the cloud-init disk is encoded in its name, so it must not >>>> be renamed or it cannot be recognized as a cloud-init disk anymore, as >>>> reported in the community forum [0]. >>>> >>>> [0]: https://forum.proxmox.com/threads/167767/ >>> >>> A user in the community forum [1] reported that if a VM is moved to >>> another node during a fence recovery, the VM will fail to migrate back, >>> e.g., if a node affinity rule prioritizes the previous node. >>> >>> This patch is correct to not allow renaming cloudinit images, but I >>> wonder if it would be a reasonable idea to allow overriding existing >>> cloudinit images on the target node as these are auto-generated? >>> >>> That would probably need a `--allow-override` flag for pvesm, which >>> would require that the target host can understand the parameter though. >>> >>> [1] https://forum.proxmox.com/threads/181516/ >>=20 >> I think we could remove left-over cloud-init images as part of the >> 'pvesr prepare-local-job' on the target? > > Ah wait, it doesn't only affect the scenario with replication. The > 'pvesm apiinfo' command was added when introducing the '--allow-rename' > flag. You could add '--allow-override', bump the API and then use that > call to check if it is understood by the target. > > Or maybe we can add some kind of preparatory tunnel command for removing > any left-over cloud-init images? Hm, currently the most likely place for this to happen seems to be for HA-managed VMs with replication jobs, but of course this might happen for other VMs as well. Bumping APIVER for '--allow-override' seems a bit much, but if there's a future use case to have that option there might be worth it. But it feels like something that could be reasonably implemented with a 'pvesm free' for the cloudinit image beforehand. Either way, this would need some attention to prevent users from overriding files not owned by the VM. I guess using a preparatory tunnel would also be an option, but I'd like to avoid to include a source of timeout (regarding the missing 'command unknown' response for mtunnel) for a relatively uncommon use case ;). Thanks for the pointers, I'll look into this!