--- title: How Many Spines Should a Leaf-and-Spine Fabric Have? «... description: A practical guide to determining the number of spine switches in a leaf-and-spine fabric. Two key factors drive the decision: the required port count (based on... canonical: https://daily.dev/posts/how-many-spines-should-a-leaf-and-spine-fabric-have-ipspace-net-blog-ldk6wzjdo twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: How Many Spines Should a Leaf-and-Spine Fabric Have? « ipSpace.net blog | daily.dev og:description: A practical guide to determining the number of spine switches in a leaf-and-spine fabric. Two key factors drive the decision: the required port count (based on... og:url: https://daily.dev/posts/how-many-spines-should-a-leaf-and-spine-fabric-have-ipspace-net-blog-ldk6wzjdo og:image: https://api.daily.dev/og/posts/ldK6WzjDo.png og:image:alt: How Many Spines Should a Leaf-and-Spine Fabric Have? « 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. # How Many Spines Should a Leaf-and-Spine Fabric Have? « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 2 min read · 0 upvotes · 0 comments ## Summary A practical guide to determining the number of spine switches in a leaf-and-spine fabric. Two key factors drive the decision: the required port count (based on leaf switch count and uplinks) and the desired redundancy level. With four uplinks per leaf and 32-port spines, you can support up to 16 leaves with two spines, needing four spines beyond that. More than two spines enables maintenance during business hours without full maintenance windows. Modern ASICs supporting 64-way ECMP make odd numbers like three spines viable, unlike older ECMP implementations that favored powers of two. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How many spine switches do I need in a leaf-and-spine fabric? The number of spines depends on two factors: required port count and desired redundancy. With four uplinks per leaf and 32-port spines, two spines support up to 16 leaf switches; beyond that, four spines are needed. Three spines work if an unused uplink is acceptable. More than two spines allow maintenance during business hours rather than requiring off-hours windows. _Network engineers sizing fabric upgrades track design trade-offs like these on daily.dev._ ### Can I use three spines in a leaf-and-spine fabric with ECMP? Yes, three spines are viable with modern ASICs that support 64-way ECMP or better. Older ECMP implementations required two or four spines (powers of two), but that constraint no longer applies to current hardware. Three spines work if you are comfortable with one unused leaf uplink and the slightly higher oversubscription ratio that results. _Engineers choosing between spine counts for new fabric deployments find relevant design discussions on daily.dev._ --- [View this post on daily.dev](https://daily.dev/posts/how-many-spines-should-a-leaf-and-spine-fabric-have-ipspace-net-blog-ldk6wzjdo) ```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":"How Many Spines Should a Leaf-and-Spine Fabric Have? « ipSpace.net blog","url":"https://daily.dev/posts/how-many-spines-should-a-leaf-and-spine-fabric-have-ipspace-net-blog-ldk6wzjdo","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/how-many-spines-should-a-leaf-and-spine-fabric-have-ipspace-net-blog-ldk6wzjdo"},"datePublished":"2026-08-11T08:54:55.318Z","dateModified":"2026-08-11T09:18:37.743Z","description":"A practical guide to determining the number of spine switches in a leaf-and-spine fabric. 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