From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 3EEB36987C for ; Tue, 23 Mar 2021 13:11:56 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 3656E2E6A1 for ; Tue, 23 Mar 2021 13:11:26 +0100 (CET) Received: from mx0.konsec.net (hbase53.h.konsec.com [88.99.94.78]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 53A7D2E697 for ; Tue, 23 Mar 2021 13:11:25 +0100 (CET) Received: from kolab.konsec.com (unknown [10.21.1.190]) by mx0.konsec.net (Postfix) with ESMTPS id 55DDD860D95 for ; Tue, 23 Mar 2021 13:03:49 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=konsec.com; s=201809; t=1616501029; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=+7GmHcUth0Aq/WsM+ywIdchLIRT555pqo850eotW/l8=; b=E0LUC3ZMAg+4x8yeVeGdML7DMkJyuzADByfaBmVeGCDeQU92zuWVzno7uYHSk9iQSlqp2U TqXErDCBdhz7n2UAJxq7J32o8be5xzY7XtkiLnn+WQVPNPWDZm/XHI1zDpMemdxX0JdJtE Wug+GkPAHcwcpy8HF6l1Xqbp8SH8r1JpycyRQTg6AZ+6QzANiN2uQXOdVu0lwJ4s4b8sYQ q+Un3+kEj9RbAENofp69uI053AQM5JGPHXpK28BjDRU+3RfvdalMSGnl7Gj82aLSUmLF9F BF2aMNUDMllVRbpMcMskfMKNmw3L5Gphn75SQWTCXsgWQROZeyxpG42dRSTBTw== Sender: martin.konold@konsec.com MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Date: Tue, 23 Mar 2021 13:03:45 +0100 From: "Konold, Martin" To: pve-user@lists.proxmox.com Reply-To: martin.konold@konsec.com Message-ID: X-Sender: martin.konold@konsec.com Organization: KONSEC GmbH Content-Transfer-Encoding: quoted-printable X-SPAM-LEVEL: Spam detection results: 0 AWL 0.250 Adjusted score from AWL reputation of From: address DKIM_SIGNED 0.1 Message has a DKIM or DK signature, not necessarily valid DKIM_VALID -0.1 Message has at least one valid DKIM or DK signature DKIM_VALID_AU -0.1 Message has a valid DKIM or DK signature from author's domain DKIM_VALID_EF -0.1 Message has a valid DKIM or DK signature from envelope-from domain SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [konsec.com] Subject: [PVE-User] mtu setting for virtual ethernet X-BeenThere: pve-user@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE user list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 23 Mar 2021 12:11:56 -0000 Hi Proxmox Users, I learned from the Proxmox forum that appending mtu=3D1 to the network=20 definition of a virtual machine instructs the virtual ethernet device to=20 inherit the mtu from the corresponding bridge. In my case net0: virtio=3DFA:FF:FF:FF:FF:D8,bridge=3Dvmbr15,mtu=3D1 and the bridge definition iface vmbr15 inet static address 10.21.15.11/24 bridge-ports enp35s0.4015 bridge-stp off bridge-fd 0 bridge-vlan-aware yes bridge-vids 2-4094 mtu 1400 According to my tests this seams to work indeed. The guest OS shows the=20 1400 mtu. Question 1: Can the mtu=3D1 (magic value for auto mtu inheritance) be mad= e=20 the default? Question 2: It seams that appending mtu=3D1 breaks the webUI. I get=20 "Unable to parse network options". Kind Regards ppa. Martin Konold -- Martin Konold - Prokurist, CTO KONSEC GmbH -=E2=81=A0 make things real Amtsgericht Stuttgart, HRB 23690 Gesch=C3=A4ftsf=C3=BChrer: Andreas Mack Im K=C3=B6ller 3, 70794 Filderstadt, Germany