--- title: OSPFv3 on Bird Needs IPv6 LLA on the Loopback Interface... description: When running OSPFv3 with the Bird routing daemon, the loopback interface (lo) is silently ignored if it lacks an IPv6 Link-Local Address (LLA), even when... canonical: https://daily.dev/posts/ospfv3-on-bird-needs-ipv6-lla-on-the-loopback-interface-ipspace-net-blog-ikfzqhrdn twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: OSPFv3 on Bird Needs IPv6 LLA on the Loopback Interface « ipSpace.net blog | daily.dev og:description: When running OSPFv3 with the Bird routing daemon, the loopback interface (lo) is silently ignored if it lacks an IPv6 Link-Local Address (LLA), even when... og:url: https://daily.dev/posts/ospfv3-on-bird-needs-ipv6-lla-on-the-loopback-interface-ipspace-net-blog-ikfzqhrdn og:image: https://api.daily.dev/og/posts/ikfzQhRdn.png og:image:alt: OSPFv3 on Bird Needs IPv6 LLA on the Loopback Interface « 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. # OSPFv3 on Bird Needs IPv6 LLA on the Loopback Interface « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 2 min read · 0 upvotes · 0 comments ## Summary When running OSPFv3 with the Bird routing daemon, the loopback interface (lo) is silently ignored if it lacks an IPv6 Link-Local Address (LLA), even when configured as a stub interface. This causes Bird to fail advertising the IPv6 prefix on the loopback via OSPFv3. The fix is to manually add a static LLA to the loopback: `ip addr add fe80::1/64 dev lo scope link`. This behavior is present in the Bird version shipping with Ubuntu 24.04 and is considered "Functions As Designed." The comments also highlight Bird's inverted Administrative Distance defaults compared to other vendors. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Why is Bird OSPFv3 not advertising the IPv6 prefix on my loopback interface? Bird OSPFv3 ignores any interface that lacks an IPv6 Link-Local Address (LLA), including loopback interfaces configured as stub interfaces. The loopback will appear in the 'Ignored' state. Adding a static LLA fixes it: run `ip addr add fe80::1/64 dev lo scope link`. This behavior is present in the Bird version shipped with Ubuntu 24.04 and is considered intentional by the Bird project. _Network engineers debugging Bird OSPFv3 quirks find edge cases like this faster on daily.dev._ ## Similar posts on daily.dev - [The Never-Ending IPv6 Loopback Prefix Saga « ipSpace.net blog](https://daily.dev/posts/the-never-ending-ipv6-loopback-prefix-saga-ipspace-net-blog-4nlhgh10l) · ipSpace.net Blog · 0 upvotes · 0 comments - [The OSPF MTU Mismatch Saga « ipSpace.net blog](https://daily.dev/posts/the-ospf-mtu-mismatch-saga-ipspace-net-blog-jmtvuzjm6) · ipSpace.net Blog · 0 upvotes · 0 comments --- Tags: [#networking](https://daily.dev/tags/networking) [View this post on daily.dev](https://daily.dev/posts/ospfv3-on-bird-needs-ipv6-lla-on-the-loopback-interface-ipspace-net-blog-ikfzqhrdn) ```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":"OSPFv3 on Bird Needs IPv6 LLA on the Loopback Interface « ipSpace.net blog","url":"https://daily.dev/posts/ospfv3-on-bird-needs-ipv6-lla-on-the-loopback-interface-ipspace-net-blog-ikfzqhrdn","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/ospfv3-on-bird-needs-ipv6-lla-on-the-loopback-interface-ipspace-net-blog-ikfzqhrdn"},"datePublished":"2026-08-11T08:52:20.355Z","dateModified":"2026-08-24T06:56:31.689Z","description":"When running OSPFv3 with the Bird routing daemon, the loopback interface (lo) is silently ignored if it lacks an IPv6 Link-Local Address (LLA), even when...","image":"https://media.daily.dev/image/upload/s--qPvKM23u--/f_auto/v1722860399/public/Placeholder%2009","thumbnailUrl":"https://media.daily.dev/image/upload/s--qPvKM23u--/f_auto/v1722860399/public/Placeholder%2009","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/ospfv3-on-bird-needs-ipv6-lla-on-the-loopback-interface-ipspace-net-blog-ikfzqhrdn","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"networking","timeRequired":"PT2M"} {"@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":"OSPFv3 on Bird Needs IPv6 LLA on the Loopback Interface « ipSpace.net blog"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/ospfv3-on-bird-needs-ipv6-lla-on-the-loopback-interface-ipspace-net-blog-ikfzqhrdn#faq","mainEntity":[{"@type":"Question","name":"Why is Bird OSPFv3 not advertising the IPv6 prefix on my loopback interface?","acceptedAnswer":{"@type":"Answer","text":"Bird OSPFv3 ignores any interface that lacks an IPv6 Link-Local Address (LLA), including loopback interfaces configured as stub interfaces. The loopback will appear in the 'Ignored' state. Adding a static LLA fixes it: run `ip addr add fe80::1/64 dev lo scope link`. This behavior is present in the Bird version shipped with Ubuntu 24.04 and is considered intentional by the Bird project. Network engineers debugging Bird OSPFv3 quirks find edge cases like this faster on daily.dev."}}]} ```