From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [IPv6:2a01:7e0:0:424::9]) by lore.proxmox.com (Postfix) with ESMTPS id 84DC11FF13C for ; Thu, 16 Apr 2026 14:47:03 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 187FE5026; Thu, 16 Apr 2026 14:47:03 +0200 (CEST) Message-ID: Date: Thu, 16 Apr 2026 14:46:27 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH proxmox-ve-rs v2 1/7] sdn: fabric: add BGP protocol support To: pve-devel@lists.proxmox.com References: <20260415111134.124720-1-h.laimer@proxmox.com> <20260415111134.124720-2-h.laimer@proxmox.com> Content-Language: en-US From: Hannes Laimer In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1776343509289 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.082 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 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_RPBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_SAFE_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. 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: OG4CRBWA3LDAJ27VCNXLBAFSH3CU64ZV X-Message-ID-Hash: OG4CRBWA3LDAJ27VCNXLBAFSH3CU64ZV X-MailFrom: h.laimer@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 2026-04-16 11:16, Gabriel Goller wrote: > On 15.04.2026 13:11, Hannes Laimer wrote: >> From: Stefan Hanreich >> >> Add BGP as a fabric protocol for eBGP unnumbered underlays. Each node >> has a mandatory, globally unique ASN for interface-based eBGP peering. >> >> Unlike OSPF and OpenFabric, BGP does not have its own FRR daemon - > > This is a bit wrong, BGP has its own frr daemon, maybe rewrite this as "the bgp > router is not exclusive to the bgp fabric"? yeah, will improve in v3, thanks! > >> the fabric config needs to coexist with EVPN in a single 'router bgp' >> block. To handle this, the fabric merges into an existing router >> rather than replacing it, using local-as to present the per-node ASN >> to underlay peers when the router already runs under the EVPN ASN. >> >> For IPv6-only nodes, the BGP router-id is derived from the IPv6 >> address using FNV-1a, since router-id must be a 32-bit value. > > Hmm this is a bit weird since the generated address is not really reachable > right? I mean, the route-id shares a format with ipv4 addresses, but it's not supposed to be ip reachable. In perl we use part of the mac, for the router-id if we don't have an ipv4 address. We can't really in rust, and this seemed like a good(maybe better? cause macs may change) approach. > > How do we handle this (frr bgp docs)?: > > To derive system-IP and anycast-IP, the default BGP instance’s router-id is > used as system-IP and the VxLAN interface’s local tunnel IP as the anycast-IP. > > > Would it be stupid to select a ipv4 address, set it on the lo interface and then > just use update-source and set the ipv6 address? > hmm, good point actually, we need v4 reachability(at least for now), just putting the derived router-id as an ipv4 address on the lo should work. just not super sure if this is more on the actually common or actually weird side of things... but I like the idea But I don't think we should do this generally when creating a bgp fabric, needing the router-id to be reachable is more of an EVPN specific requirement I think the alternative would be to require a configured v4 prefix on fabrics if used for EVPN either way it's more of an EVPN, than fabric, concern I think >> Co-authored-by: Hannes Laimer >> Signed-off-by: Stefan Hanreich >> Signed-off-by: Hannes Laimer > > Maybe a few more tests with other existing fabrics, e.g. ospf and openfabric? > These are quite easy to add, so adding a few more won't hurt.