--- title: Cloudflare’s eBPF Replatforming Part 5: Tips for... description: Cloudflare explains how it operates eBPF programs safely across more than 330 global locations. The kernel's BPF verifier rejects programs with invalid memory... canonical: https://daily.dev/posts/cloudflare-s-ebpf-replatforming-part-5-tips-for-operating-ebpf-at-scale-8dsmnuhdy twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Cloudflare’s eBPF Replatforming Part 5: Tips for Operating eBPF at Scale | daily.dev og:description: Cloudflare explains how it operates eBPF programs safely across more than 330 global locations. The kernel's BPF verifier rejects programs with invalid memory... og:url: https://daily.dev/posts/cloudflare-s-ebpf-replatforming-part-5-tips-for-operating-ebpf-at-scale-8dsmnuhdy og:image: https://api.daily.dev/og/posts/8dsMNUhdy.png og:image:alt: Cloudflare’s eBPF Replatforming Part 5: Tips for Operating eBPF at Scale 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. # Cloudflare’s eBPF Replatforming Part 5: Tips for Operating eBPF at Scale **[eBPF](https://daily.dev/sources/ebpf)** · 6 min read · 0 upvotes · 0 comments ## Summary Cloudflare explains how it operates eBPF programs safely across more than 330 global locations. The kernel's BPF verifier rejects programs with invalid memory access, infinite loops, or stack use over 512 bytes (less with tail calls) at load time. Updates go through pre-production testing, including VET and, for complex issues like race conditions, virtual machine load testing, followed by a multi-day staged rollout starting with canary data centers. Critical components like Tubular use atomic bpf_link swaps so traffic is not dropped between old and new versions, a tableflip-based graceful reload keeps the data plane running during daemon upgrades, and pinned BPF maps on bpffs let kernel programs keep running even if the userspace daemon crashes. A single master binary with configurable code paths handles per-location rule differences instead of separate builds per site. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How does Cloudflare upgrade eBPF programs in production without dropping packets? Cloudflare uses bpf_link to atomically swap programs: the new program loads into the kernel, then the existing link is updated to point to it, so traffic is always handled by either the old or new version with no gap. The deployment tool also checks a hash ('tag') of the running program and aborts if it doesn't match the expected version, preventing inconsistent upgrades. _Teams rolling out kernel-level changes safely can follow eBPF deployment patterns like this via daily.dev._ ### What happens to a running eBPF/XDP program if the userspace management daemon crashes? The eBPF program in the kernel keeps running undisturbed because its state, such as active socket bindings and forwarding tables, is stored in pinned BPF maps on the bpffs filesystem, decoupled from the userspace process. Without pinned maps, a crash during a control plane outage could leave a server with no XDP/BPF pipeline, dropping packets or misrouting them locally. _Engineers hardening data-plane resilience can track real-world eBPF crash-recovery patterns on daily.dev._ ### What are the kernel's BPF verifier guarantees for loaded eBPF programs? The BPF verifier statically analyzes every code path before a program loads, rejecting programs that could dereference a NULL pointer, access out-of-bounds memory, or contain non-terminating loops. It also enforces a 512-byte stack size limit (smaller for programs using BPF_MAP_TYPE_PROG_ARRAY tail calls), rejecting oversized programs at load time. _Developers evaluating eBPF's safety guarantees before adopting it can follow this kind of deep dive on daily.dev._ ## Similar posts on daily.dev - [Cloudflare’s eBPF Replatforming Part 3: Technical Challenges Implementing eBPF](https://daily.dev/posts/cloudflare-s-ebpf-replatforming-part-3-technical-challenges-implementing-ebpf-wcp5jat0v) · eBPF · 0 upvotes · 0 comments - [Cloudflare’s eBPF Replatforming Part 1: The eBPF Pivot – From Hardware Lock-in to Programmable Networking](https://daily.dev/posts/cloudflare-s-ebpf-replatforming-part-1-the-ebpf-pivot-from-hardware-lock-in-to-programmable-netwo-qcdggfpuw) · eBPF · 0 upvotes · 0 comments - [How eBPF Empowers Developers to Observe Inside the Linux Kernel in a Safe and Unintrusive Way](https://daily.dev/posts/how-ebpf-empowers-developers-to-observe-inside-the-linux-kernel-in-a-safe-and-unintrusive-way-jhmpnwjer) · InfoQ · 0 upvotes · 0 comments - [What Is eBPF? Use Cases, Benefits, and Key Differences](https://daily.dev/posts/what-is-ebpf-use-cases-benefits-and-key-differences-5dgqadloo) · Isovalent · 3 upvotes · 0 comments - [Cloudflare’s eBPF Replatforming Part 4: Observability, Operations, and Reliability Improvements from eBPF](https://daily.dev/posts/cloudflare-s-ebpf-replatforming-part-4-observability-operations-and-reliability-improvements-from-k5xeelty4) · eBPF · 3 upvotes · 1 comments --- Tags: [#linux](https://daily.dev/tags/linux), [#cloudflare](https://daily.dev/tags/cloudflare) [View this post on daily.dev](https://daily.dev/posts/cloudflare-s-ebpf-replatforming-part-5-tips-for-operating-ebpf-at-scale-8dsmnuhdy) ```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":"Cloudflare’s eBPF Replatforming Part 5: Tips for Operating eBPF at Scale","url":"https://daily.dev/posts/cloudflare-s-ebpf-replatforming-part-5-tips-for-operating-ebpf-at-scale-8dsmnuhdy","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/cloudflare-s-ebpf-replatforming-part-5-tips-for-operating-ebpf-at-scale-8dsmnuhdy"},"datePublished":"2026-10-29T22:47:51.515Z","dateModified":"2026-10-29T22:51:45.373Z","description":"Cloudflare explains how it operates eBPF programs safely across more than 330 global locations. 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