{"id":82203,"date":"2020-09-22T09:30:12","date_gmt":"2020-09-22T16:30:12","guid":{"rendered":""},"modified":"2025-06-24T10:46:31","modified_gmt":"2025-06-24T17:46:31","slug":"calico-for-windows-goes-open-source","status":"publish","type":"post","link":"https:\/\/opensource.microsoft.com\/blog\/2020\/09\/22\/calico-for-windows-goes-open-source\/","title":{"rendered":"Calico for Windows goes open source"},"content":{"rendered":"\n<p>Since Windows worker node support reached general availability in Kubernetes, Microsoft and Tigera have listened closely to feedback from the community. A big contention point of Windows container users in the Kubernetes community is: \u201cOne of the most important open source network policy tools in the market is not available for Windows.\u201d This is limiting the adoption of Windows worker nodes for Kubernetes in environments big and small as customers cannot fulfill their policy and compliance requirements like they could address them in Linux.<\/p>\n\n\n\n<p>Microsoft and Tigera have been working together to close several significant gaps in the Windows container networking stack. This work included enabling Direct Server Return, enhanced policy, packet logging, expanded firewall support in the Host Networking Service of Windows, multi-subnet support, and many more large and small improvements.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"now-for-the-good-news\">Now for the good news<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>We are excited to share that with Calico 3.16, Windows container network policy support is now available in open source Calico. See the <a href=\"https:\/\/docs.projectcalico.org\/release-notes\/\">release notes<\/a> for more details.<\/li>\n\n\n\n<li>With this release, Windows containers can be deployed and secured in Azure, any other cloud computing provider, or on-premises using networking components in Windows Server and Calico network policy.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"more-details\">More details<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Calico for Windows version 3.16 can be found on the <a href=\"https:\/\/projectcalico.org\">Calico site<\/a>.<\/li>\n\n\n\n<li>If you have any questions or concerns contact us at the Calico User Slack <a href=\"https:\/\/calicousers.slack.com\/archives\/CF9M1U9RV\">Windows channel<\/a>.<\/li>\n\n\n\n<li>If you want to try it out check out the quick start guide on <a href=\"https:\/\/docs.projectcalico.org\/getting-started\/windows-calico\/quickstart\">projectcalico.org<\/a>.<\/li>\n<\/ul>\n\n\n\n<p>The release announcement from Calico can also be found on the <a href=\"https:\/\/www.tigera.io\/blog\/tigera-announces-open-source-calico-for-windows-and-collaboration-with-microsoft\/\">Tigera blog<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Since Windows worker node support reached general availability in Kubernetes, Microsoft and Tigera have listened closely to feedback from the community. A big contention point of Windows container users in the Kubernetes community is: \u201cOne of the most important open source network policy tools in the market is not available for Windows.<\/p>\n","protected":false},"author":5562,"featured_media":95482,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"msxcm_post_with_no_image":false,"ep_exclude_from_search":false,"_classifai_error":"","_classifai_text_to_speech_error":"","footnotes":""},"post_tag":[2272],"content-type":[346],"topic":[2241,2242],"programming-languages":[],"coauthors":[1671],"class_list":["post-82203","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","tag-microsoft","content-type-news","topic-cloud","topic-containers","review-flag-3-1593580442-169","review-flag-gener-1593580751-533"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.2 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Calico for Windows goes open source | Microsoft Open Source Blog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/opensource.microsoft.com\/blog\/2020\/09\/22\/calico-for-windows-goes-open-source\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Calico for Windows goes open source | Microsoft Open Source Blog\" \/>\n<meta property=\"og:description\" content=\"Since Windows worker node support reached general availability in Kubernetes, Microsoft and Tigera have listened closely to feedback from the community. A big contention point of Windows container users in the Kubernetes community is: \u201cOne of the most important open source network policy tools in the market is not available for Windows.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/opensource.microsoft.com\/blog\/2020\/09\/22\/calico-for-windows-goes-open-source\/\" \/>\n<meta property=\"og:site_name\" content=\"Microsoft Open Source Blog\" \/>\n<meta property=\"article:published_time\" content=\"2020-09-22T16:30:12+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2025-06-24T17:46:31+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/opensource.microsoft.com\/blog\/wp-content\/uploads\/2024\/06\/MSC24-Japan-business-Getty-1024531730-rgb.png\" \/>\n\t<meta property=\"og:image:width\" content=\"1170\" \/>\n\t<meta property=\"og:image:height\" content=\"640\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/png\" \/>\n<meta name=\"author\" content=\"Mike Kostersitz\" \/>\n<meta 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