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 951401FF183 for ; Wed, 16 Jul 2025 15:14:00 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 143C41135D; Wed, 16 Jul 2025 15:10:02 +0200 (CEST) Date: Wed, 16 Jul 2025 15:09:56 +0200 From: Gabriel Goller To: pve-devel@lists.proxmox.com Message-ID: <2mmv7vkftmed7lkfsdw2caqpjr3hjbfvjhqvm2iujlxh2prsif@gcmsnd2y26cs> Mail-Followup-To: pve-devel@lists.proxmox.com References: <20250702145101.894299-1-g.goller@proxmox.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20241002-35-39f9a6 X-SPAM-LEVEL: Spam detection results: 0 AWL -0.011 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_MSPIKE_H2 0.001 Average reputation (+2) SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: Re: [pve-devel] [PATCH access-control/cluster/docs/gui-tests/manager/network/proxmox{, -firewall, -ve-rs, -perl-rs, -widget-toolkit} v4 00/76] Add SDN Fabrics X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Proxmox VE development discussion Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: pve-devel-bounces@lists.proxmox.com Sender: "pve-devel" On 09.07.2025 13:27, Gabriel Goller wrote: >We've been thinking more about the ipv6 forwarding issue and still >aren't sure about the best approach, so we'd like to hear other >opinions. > > >Problem >======= > >As explained in the commit "frr: add global ipv6 forwarding" we enabled >*global* ipv6 forwarding for two reasons: > > 1) So that non-fullmesh setups work. > 2) Because there is no per-interface forwarding like in ipv4. > >This fixes non-fullmesh setups, but it forces ipv6 forwarding on every >interface the user configures, now and in the future. > >Another problem is that we can't realistically disable global forwarding >once we enable it. That would be a breaking change that's hard to >mitigate/handle. So enabling global ipv6 forwarding is a one-way >decision. > > >Solutions >========= > >The simplest solution would be to prompt the user to enable ipv6 >forwarding manually. We could display a popup when creating an >ipv6 fabric, instructing them to add `ipv6 forwarding` to >`/etc/frr/frr.conf.local`. This approach leaves the decision with the >user and treats global ipv6 forwarding as a user-configuration rather >than a pve-configuration setting. > >The second solution we prepared would be to add a new sysctl option to the >kernel which allows us to do per-interface ipv6 forwarding. >The patch isn't applied yet but is available here: >https://lore.kernel.org/netdev/20250707094307.223975-1-g.goller@proxmox.com/T/#u >We would apply this patch to our kernel and then modify ifupdown2 so >that `ip6-forward` enables the `force_forwarding` sysctl (from the >patch) along with the regular `forwarding` one. This wouldn't really be >a breaking change since the `ip6-forward` option doesn't actually enable >forwarding right now. The option is also pretty obscure and >undocumented, so we think it would be safe. > >We'd appreciate your feedback! We decided to not enable IPv6 forwarding, but prompt the user to enable it themselves. _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel