--- title: IBGP Is the Better EBGP « ipSpace.net blog | daily.dev description: An exploration of using IBGP as a replacement for EBGP in data center fabrics, mirroring the 'BGP Is the Better IGP' pattern. The key requirements are... canonical: https://daily.dev/posts/ibgp-is-the-better-ebgp-ipspace-net-blog-3e8zd6cqz twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: IBGP Is the Better EBGP « ipSpace.net blog | daily.dev og:description: An exploration of using IBGP as a replacement for EBGP in data center fabrics, mirroring the 'BGP Is the Better IGP' pattern. The key requirements are... og:url: https://daily.dev/posts/ibgp-is-the-better-ebgp-ipspace-net-blog-3e8zd6cqz og:image: https://api.daily.dev/og/posts/3E8zD6cqz.png og:image:alt: IBGP Is the Better EBGP « ipSpace.net blog og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # IBGP Is the Better EBGP « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 7 min read · 0 upvotes · 0 comments ## Summary An exploration of using IBGP as a replacement for EBGP in data center fabrics, mirroring the 'BGP Is the Better IGP' pattern. The key requirements are establishing IBGP sessions between directly connected interface addresses (not loopbacks) and configuring route reflectors to change BGP next hops — a behavior that technically violates RFC 4456 Section 10's SHOULD NOT directive. A working proof-of-concept is demonstrated using Arista EOS with the 'neighbor next-hop-peer' command. Benefits include no need for AS number management, no BGP update interval concerns, and no valley-free routing issues. Drawbacks include reliance on non-standard implementation behavior, untested BFD compatibility, and the risk of being the sole user of this design with limited vendor support. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Can I build a data center fabric using only IBGP instead of EBGP, and what are the requirements? An IBGP-only data center fabric is technically feasible with two key requirements: IBGP sessions must be established between directly connected interface addresses (not loopbacks, since there is no IGP to propagate loopback prefixes), and spine switches acting as route reflectors must change BGP next hops to the peer IP address. On Arista EOS, the 'neighbor next-hop-peer' command handles the next-hop rewrite. This violates RFC 4456 Section 10's SHOULD NOT directive, so not all implementations support it. _Network engineers evaluating BGP fabric designs track implementation-specific behavior like this on daily.dev._ ### What does the 'neighbor next-hop-peer' command do on Arista EOS in an IBGP route reflector setup? The 'neighbor next-hop-peer' command on Arista EOS sets the BGP next hop in incoming BGP updates to the peer's IP address. In an IBGP-only fabric, this allows route reflectors to rewrite next hops on reflected routes, mimicking the next-hop behavior of EBGP sessions. Without this, IBGP's standard behavior of preserving next hops across the AS would break reachability in a fabric with no IGP. _Arista EOS-specific BGP behavior like this surfaces regularly for engineers building leaf-spine fabrics on daily.dev._ ### What are the trade-offs of using IBGP instead of EBGP in a leaf-spine data center fabric? Benefits of an IBGP-only fabric include no need to manage BGP AS numbers (CLUSTER_LIST replaces AS_PATH for loop prevention), no BGP update interval delays (most implementations don't batch IBGP updates), and no valley-free routing or path hunting concerns since leaf switches won't reflect IBGP routes. Drawbacks include reliance on non-standard next-hop behavior that violates RFC 4456, unverified BFD compatibility on IBGP sessions, and minimal real-world adoption meaning vendor bug support is unlikely. _Engineers deciding between IBGP and EBGP for fabric design find comparative analysis like this on daily.dev._ --- Tags: [#bgp](https://daily.dev/tags/bgp), [#networking](https://daily.dev/tags/networking) [View this post on daily.dev](https://daily.dev/posts/ibgp-is-the-better-ebgp-ipspace-net-blog-3e8zd6cqz) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"IBGP Is the Better EBGP « ipSpace.net blog","url":"https://daily.dev/posts/ibgp-is-the-better-ebgp-ipspace-net-blog-3e8zd6cqz","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/ibgp-is-the-better-ebgp-ipspace-net-blog-3e8zd6cqz"},"datePublished":"2026-08-11T08:51:56.133Z","dateModified":"2026-10-15T02:24:48.336Z","description":"An exploration of using IBGP as a replacement for EBGP in data center fabrics, mirroring the 'BGP Is the Better IGP' pattern. 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