--- title: netlab: Change Stub Networks into Loopbacks «... description: netlab release 1.5.0 introduced a loopback link type to work around the limited number of network interfaces available on virtual machines. By setting `type:... canonical: https://daily.dev/posts/netlab-change-stub-networks-into-loopbacks-ipspace-net-blog-9ekak5sff twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: netlab: Change Stub Networks into Loopbacks « ipSpace.net blog | daily.dev og:description: netlab release 1.5.0 introduced a loopback link type to work around the limited number of network interfaces available on virtual machines. By setting `type:... og:url: https://daily.dev/posts/netlab-change-stub-networks-into-loopbacks-ipspace-net-blog-9ekak5sff og:image: https://api.daily.dev/og/posts/9ekAk5sff.png og:image:alt: netlab: Change Stub Networks into Loopbacks « 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: Change Stub Networks into Loopbacks « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 3 min read · 0 upvotes · 0 comments ## Summary netlab release 1.5.0 introduced a loopback link type to work around the limited number of network interfaces available on virtual machines. By setting `type: loopback` on stub links (single-node links), netlab uses loopback interfaces instead of LAN interfaces, conserving physical interface slots. System-wide or per-device behavior can be controlled via `defaults.links.stub_loopback` or `defaults.devices..features.stub_loopback`. Upgrade via `pip3 install --upgrade networklab`. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do I convert stub links to loopback interfaces in netlab to avoid hitting the VM interface limit? Set `type: loopback` on any single-node link in your netlab topology, or enable it globally with `defaults.links.stub_loopback: True`. Per-device control is available via `defaults.devices..features.stub_loopback`. Loopback links still behave as stub links — IP prefixes are drawn from the LAN pool — but they consume a loopback interface instead of a physical adapter slot. This feature was introduced in netlab 1.5.0. _Network engineers hitting interface limits in virtual labs track netlab releases and workarounds on daily.dev._ ### What is the maximum number of network interfaces supported per VM in vSphere and vagrant-libvirt? vSphere supports up to 10 network interfaces per VM, and the default for vagrant-libvirt is eight. KVM limits vary by vendor but are commonly cited around 25, though a Nexus 9300v has been brought up with 40 adapters. These limits matter when emulating large numbers of edge subnets in virtual networking labs. _Engineers designing virtual lab topologies keep up with platform constraints like these on daily.dev._ ## Similar posts on daily.dev - [netlab 26.10: SRv6, More Netmiko « ipSpace.net blog](https://daily.dev/posts/netlab-26-10-srv6-more-netmiko-ipspace-net-blog-1cocu1zdt) · ipSpace.net Blog · 0 upvotes · 0 comments --- [View this post on daily.dev](https://daily.dev/posts/netlab-change-stub-networks-into-loopbacks-ipspace-net-blog-9ekak5sff) ```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: Change Stub Networks into Loopbacks « ipSpace.net blog","url":"https://daily.dev/posts/netlab-change-stub-networks-into-loopbacks-ipspace-net-blog-9ekak5sff","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/netlab-change-stub-networks-into-loopbacks-ipspace-net-blog-9ekak5sff"},"datePublished":"2026-08-11T08:52:59.209Z","dateModified":"2026-08-11T09:09:05.628Z","description":"netlab release 1.5.0 introduced a loopback link type to work around the limited number of network interfaces available on virtual machines. 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