--- title: netlab: VRF Instantiation on Lab Devices « ipSpace.net blog description: netlab minimizes VRF configuration on lab devices by applying a simple rule: a VRF is only instantiated on a device if that device has at least one interface... canonical: https://daily.dev/posts/netlab-vrf-instantiation-on-lab-devices-ipspace-net-blog-zppirzyj7 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: netlab: VRF Instantiation on Lab Devices « ipSpace.net blog | daily.dev og:description: netlab minimizes VRF configuration on lab devices by applying a simple rule: a VRF is only instantiated on a device if that device has at least one interface... og:url: https://daily.dev/posts/netlab-vrf-instantiation-on-lab-devices-ipspace-net-blog-zppirzyj7 og:image: https://api.daily.dev/og/posts/ZppirzyJ7.png og:image:alt: netlab: VRF Instantiation on Lab Devices « 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. # netlab: VRF Instantiation on Lab Devices « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 4 min read · 0 upvotes · 0 comments ## Summary netlab minimizes VRF configuration on lab devices by applying a simple rule: a VRF is only instantiated on a device if that device has at least one interface in that VRF. The post walks through several scenarios — basic PE router setups, inter-VRF route leaking, loopback-only VRFs, and group-based VRF assignment — showing how to correctly trigger VRF instantiation. Key insight: setting the global vrf.loopback parameter alone is insufficient; the VRF must also be referenced in the node or group definition to give netlab a reason to configure it. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### When does netlab configure a VRF on a lab device? netlab configures a VRF on a lab device only if that device has at least one interface in that VRF. For loopback-only VRFs, setting the global vrf.loopback parameter alone is not enough — the VRF must also be explicitly referenced in the node or group definition to trigger loopback interface creation and give netlab a reason to instantiate the VRF. _Network engineers building complex lab topologies track netlab behaviour like this on daily.dev._ ### How do I create a loopback-only VRF in netlab without adding external hosts? Set vrf.loopback: True globally and reference the VRF in each node's definition (e.g., vrfs.red: under each node) or via a group with vrfs.red: set. This combination triggers loopback interface creation inside the VRF, satisfying netlab's rule that a VRF must have at least one interface to be instantiated and configured on a device. _Those building MPLS VPN labs with netlab find related patterns and gotchas discussed on daily.dev._ --- Tags: [#networking](https://daily.dev/tags/networking), [#bgp](https://daily.dev/tags/bgp) [View this post on daily.dev](https://daily.dev/posts/netlab-vrf-instantiation-on-lab-devices-ipspace-net-blog-zppirzyj7) ```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":"netlab: VRF Instantiation on Lab Devices « ipSpace.net blog","url":"https://daily.dev/posts/netlab-vrf-instantiation-on-lab-devices-ipspace-net-blog-zppirzyj7","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/netlab-vrf-instantiation-on-lab-devices-ipspace-net-blog-zppirzyj7"},"datePublished":"2026-08-11T08:55:46.789Z","dateModified":"2026-08-11T09:26:32.253Z","description":"netlab minimizes VRF configuration on lab devices by applying a simple rule: a VRF is only instantiated on a device if that device has at least one interface...","image":"https://media.daily.dev/image/upload/s--2-1xRawN--/f_auto/v1722860399/public/Placeholder%2011","thumbnailUrl":"https://media.daily.dev/image/upload/s--2-1xRawN--/f_auto/v1722860399/public/Placeholder%2011","isAccessibleForFree":true,"articleSection":"ipSpace.net Blog","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"ipSpace.net Blog","logo":"https://media.daily.dev/image/upload/s--xS7E82MT--/f_auto,q_auto/v1786438303/logos/ipspace?_a=BAMAMicg0","url":"https://daily.dev/sources/ipspace"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/netlab-vrf-instantiation-on-lab-devices-ipspace-net-blog-zppirzyj7","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"networking,bgp","timeRequired":"PT4M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"ipSpace.net Blog","item":"https://daily.dev/sources/ipspace"},{"@type":"ListItem","position":3,"name":"netlab: VRF Instantiation on Lab Devices « ipSpace.net blog"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/netlab-vrf-instantiation-on-lab-devices-ipspace-net-blog-zppirzyj7#faq","mainEntity":[{"@type":"Question","name":"When does netlab configure a VRF on a lab device?","acceptedAnswer":{"@type":"Answer","text":"netlab configures a VRF on a lab device only if that device has at least one interface in that VRF. 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