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 6B1B7C960 for ; Wed, 4 May 2022 15:49:29 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 4667428C43 for ; Wed, 4 May 2022 15:49:29 +0200 (CEST) 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 id 5311B28C38 for ; Wed, 4 May 2022 15:49:28 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id AFBFC4313F; Wed, 4 May 2022 15:40:00 +0200 (CEST) Date: Wed, 4 May 2022 15:39:59 +0200 From: Stoiko Ivanov To: Martin Dziobek Cc: Proxmox VE user list Message-ID: <20220504153959.19ffadc1@rosa.proxmox.com> In-Reply-To: <20220504141059.48ab3303@schleppmd.hlrs.de> References: <20220504141059.48ab3303@schleppmd.hlrs.de> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 0.202 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% 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 - Subject: Re: [PVE-User] Proxmox VE 7.2 - Problem of understanding 'bridge-disable-mac-learning' 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: Wed, 04 May 2022 13:49:29 -0000 hi, On Wed, 4 May 2022 14:10:59 +0200 Martin Dziobek wrote: > Dear all, > > In the Release Notes of 7.2, it says: > > "Administrators can now disable MAC learning on a bridge in /etc/network/interfaces with the bridge-disable-mac-learning flag. > This reduces the number of packets flooded on all ports (for unknown MAC addresses), preventing issues with certain hosting > providers (for example, Hetzner), which resulted in the Proxmox VE node getting disconnected" > > where as in descriptions of how to disable mac bridge learning > for example on https://www.xmodulo.com/disable-mac-learning-linux-bridge.html > > it says: > > "Once MAC learning is turned off, a Linux bridge will flood every incoming packet to the rest of the ports. > Understand this implication before proceeding." > > So flooding is reduced *or* increased ... > > May someone shed a light on this ? I think the commit message of the relevant commit describes the situation quite well: https://git.proxmox.com/?p=pve-common.git;a=commit;h=354ec8dee37d481ebae49b488349a8e932dce736 it disables learning on the individual ports - but at the same time also the unicast_flood flag is set to false - see `man 8 bridge` - so I'd expect the combination of the 2 to work as advertised (and will try to rephrase the release note entry a bit too be less confusing) I hope this helps! Best regards, stoiko