{"id":1241,"date":"2023-04-16T12:28:59","date_gmt":"2023-04-16T11:28:59","guid":{"rendered":"https:\/\/blog.thomarite.uk\/?p=1241"},"modified":"2023-04-16T12:28:59","modified_gmt":"2023-04-16T11:28:59","slug":"bgp-site-of-origin-soo","status":"publish","type":"post","link":"https:\/\/blog.thomarite.uk\/index.php\/2023\/04\/16\/bgp-site-of-origin-soo\/","title":{"rendered":"BGP Site of Origin (SoO)"},"content":{"rendered":"\n<p>SoO is something that I have read and I forget often so trying to stick it in my mind here. Found this <a href=\"https:\/\/learningnetwork.cisco.com\/s\/article\/bgp-site-of-origin-soo-concepts-amp-configuration\">link<\/a> that I think it is quite good.<\/p>\n\n\n\n<p>Definition:<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">Ensuring a loop-free network in particular multi-homed MPLS Layer 3 VPN sites. BGP SoO is a tag that is appended on BGP updates to allow a peer (PE) to mark a particular prefix as belonging to a particular site. \n\nIn certain MPLS L3 VPN configurations, the BGP AS-Path may not provide the granularity needed to prevent a loop in the control-plane. For example when your CPEs in a site peers with PEs (multisite) from the SP using the same ASN, that means you need to use \"allow-as in\" in your CPEs. <\/pre>\n\n\n\n<p>Scenario:<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"883\" height=\"780\" src=\"https:\/\/blog.thomarite.uk\/wp-content\/uploads\/2023\/04\/image-6.png\" alt=\"\" class=\"wp-image-1242\" srcset=\"https:\/\/blog.thomarite.uk\/wp-content\/uploads\/2023\/04\/image-6.png 883w, https:\/\/blog.thomarite.uk\/wp-content\/uploads\/2023\/04\/image-6-300x265.png 300w, https:\/\/blog.thomarite.uk\/wp-content\/uploads\/2023\/04\/image-6-768x678.png 768w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 1362px) 62vw, 840px\" \/><\/figure>\n\n\n\n<p><\/p>\n\n\n\n<p>This scenario has two issues:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Suboptimal routing<\/li>\n\n\n\n<li>Routing loop under failure.<\/li>\n<\/ul>\n\n\n\n<p>Solution:<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">Configure a unique SoO code for each multihomed site on the PE routers.<\/pre>\n\n\n\n<p>This is just an intro as I want to create a lab with this.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>SoO is something that I have read and I forget often so trying to stick it in my mind here. Found this link that I think it is quite good. Definition: Ensuring a loop-free network in particular multi-homed MPLS Layer 3 VPN sites. BGP SoO is a tag that is appended on BGP updates to &hellip; <a href=\"https:\/\/blog.thomarite.uk\/index.php\/2023\/04\/16\/bgp-site-of-origin-soo\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;BGP Site of Origin (SoO)&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-1241","post","type-post","status-publish","format-standard","hentry","category-networks"],"_links":{"self":[{"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/posts\/1241","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/comments?post=1241"}],"version-history":[{"count":1,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/posts\/1241\/revisions"}],"predecessor-version":[{"id":1243,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/posts\/1241\/revisions\/1243"}],"wp:attachment":[{"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/media?parent=1241"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/categories?post=1241"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.thomarite.uk\/index.php\/wp-json\/wp\/v2\/tags?post=1241"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}