{"id":48,"date":"2017-09-13T17:17:25","date_gmt":"2017-09-13T15:17:25","guid":{"rendered":"http:\/\/www.quisted.net\/?p=48"},"modified":"2017-09-13T17:17:25","modified_gmt":"2017-09-13T15:17:25","slug":"ospf-lsdb-and-lsa","status":"publish","type":"post","link":"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/","title":{"rendered":"OSPF LSDB and LSA"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_80 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/#OSPF_Link-State_Database_LSDB\" >OSPF Link-State Database (LSDB)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/#OSPF_types_of_Link_State_Advertisement_LSA\" >OSPF types of Link State Advertisement (LSA)<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/#Type_1_Router_LSA\" >Type 1: Router LSA<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/#Type_2_Network_LSA\" >Type 2: Network LSA<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/#Type_3_Summary_LSA\" >Type 3: Summary LSA<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/#Type_4_Summary_ASBR_LSA\" >Type 4: Summary ASBR LSA<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/#Type_5_AS_Summary_external_LSA\" >Type 5: AS Summary external LSA<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.quisted.net\/index.php\/2017\/09\/13\/ospf-lsdb-and-lsa\/#Type_7_Not-so-stubby_area_LSA\" >Type 7: Not-so-stubby area LSA<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"OSPF_Link-State_Database_LSDB\"><\/span><strong>OSPF Link-State Database (LSDB)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li>Each router stores it&#8217;s LSA in it&#8217;s LSDB.<\/li>\n<li>Each router within the <strong>same area<\/strong> should have the same LSDB information.<\/li>\n<li>SPF algortithm for each area it is connected to.<\/li>\n<li>The router thinks it&#8217;s the root of the tree and draws branches via SPF<\/li>\n<li>LSAs in OSPF LSDB are pieces that the SPF process uses.<\/li>\n<li>OSPF poisons LSA by setting max-age (3600).<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"OSPF_types_of_Link_State_Advertisement_LSA\"><\/span><strong>OSPF types of Link State Advertisement (LSA)<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li>Type 1: Router LSA<\/li>\n<li>Type 2: Network LSA<\/li>\n<li>Type 3: Summary LSA<\/li>\n<li>Type 4: Summary ASBR LSA<\/li>\n<li>Type 5: Autonomous system external LSA<\/li>\n<li>Type 6: Multicast OSPF LSA<\/li>\n<li>Type 7: Not-so-stubby area LSA<\/li>\n<li>Type 8: External attribute LSA for BGP<\/li>\n<\/ul>\n<p><!--more--><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Type_1_Router_LSA\"><\/span><span style=\"color: #3366ff;\"><strong>Type 1: Router LSA<\/strong><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>show ip ospf database router (Router Link states)<br \/>\nshow ip ospf database router 1.1.1.1<\/p>\n<ul>\n<li>Every router creates <strong>one Type 1 LSA<\/strong> and floods it throughout the same OSPF Area.<\/li>\n<li>Router creates <strong>on Type 1 LSA <\/strong>for all links in each area.<\/li>\n<li>LSA is stored in it&#8217;s own database and floods it out (224.0.0.5\/224.0.0.6 DR).<\/li>\n<li>Can&#8217;t be filtered, can&#8217;t be summerized.<\/li>\n<li>Can&#8217;t go between areas, they stop at ABR.<\/li>\n<li>All Type 1 LSAs are listed under Router Link States (Area x). <em>Show ip ospf database (router)<\/em><\/li>\n<li>OSPF identifies a Type 1 LSA using a <strong>32bit link-state identified (<em>LSID<\/em>).<\/strong><\/li>\n<\/ul>\n<p><strong>Type 1 LSA information about the attached links:<\/strong><\/p>\n<ul>\n<li><strong>Interface with no neighbors:<\/strong>\n<ul>\n<li><em><span style=\"color: #339966;\">subnet\/mask<\/span> is advertised<\/em><\/li>\n<li><em>link connected to a stub network<\/em><\/li>\n<\/ul>\n<\/li>\n<li><strong>Interface connected to DR:<\/strong>\n<ul>\n<li><em>the <span style=\"color: #3366ff;\">IP adress of the DR<\/span> is send<br \/>\n<\/em><\/li>\n<li><em>Link connected to a transit network<\/em><\/li>\n<\/ul>\n<\/li>\n<li><strong>Interface with no DR:<\/strong>\n<ul>\n<li><em>it lists the <span style=\"color: #ff9900;\">neighbor&#8217;s RID<\/span><\/em><\/li>\n<li><em>Link connected to another router (point to point)<\/em><\/li>\n<li><em>stub link so the <span style=\"color: #339966;\">subnet+mask<\/span> is send<\/em><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Type_2_Network_LSA\"><\/span><span style=\"color: #3366ff;\"><strong>Type 2: Network LSA<\/strong><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>show ip ospf database (Network Link states)<br \/>\nshow ip ospf database network<\/p>\n<ul>\n<li>Type 2 LSA is generated for multi-access Networks (Needs a DR).<\/li>\n<li>Type 2 LSA is generated by DR.<\/li>\n<li>Contains the <span style=\"color: #339966;\">subnet\/mask,<\/span><\/li>\n<li>Contains the <span style=\"color: #ff0000;\">neighbors,<\/span><\/li>\n<li>Once a DR is elected it says as a DR (so the SPF tree doesn&#8217;t have to be rebuild).<\/li>\n<li>If the DR fails, the BDR takes over.<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Type_3_Summary_LSA\"><\/span><span style=\"color: #3366ff;\"><strong>Type 3: Summary LSA<br \/>\n<\/strong><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>show ip ospf database (Summary Net Link States)<br \/>\nshow ip ospf database summary<\/p>\n<ul>\n<li>Type 3 LSA are used when there are multiple <span style=\"color: #800080;\">areas.<\/span><\/li>\n<li>Type 3 LSA sends the <span style=\"color: #339966;\">subnet(s)\/mask(s)<\/span> from one <span style=\"color: #800080;\">area<\/span> to another <span style=\"color: #800080;\">area.<\/span><\/li>\n<li><span style=\"color: #800080;\">Areas<\/span> are used to reduce memory and CPU resource.<\/li>\n<li><span style=\"color: #ff9900;\">ABRs<\/span> are used to connect different<span style=\"color: #800080;\"> areas.<\/span><\/li>\n<li><em>Type 1 LSA<\/em> and <em>Type 2 LSA<\/em> are not adverstived from one <span style=\"color: #339966;\">area<\/span> to another via <span style=\"color: #ff9900;\">ABRs.<\/span><\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Type_4_Summary_ASBR_LSA\"><\/span><span style=\"color: #3366ff;\"><strong>Type 4: Summary ASBR LSA<\/strong><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li>Only seen with an ASBR(0) in your network<\/li>\n<li>Send from the ABR(0\/1) (can reach the ASBR(0) through me) to his area<\/li>\n<li>Can&#8217;t be flooded in the next area\n<ul>\n<li>ABR(1\/2) makes a NEW Type 4 LSA<\/li>\n<li>Can reach ASBR(0) through me ABR(1\/2)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Type_5_AS_Summary_external_LSA\"><\/span><span style=\"color: #3366ff;\"><strong>Type 5: AS Summary external LSA<\/strong><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li>Created with redistribution<\/li>\n<li>Only send from ASBR<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"Type_7_Not-so-stubby_area_LSA\"><\/span><strong><span style=\"color: #3366ff;\">Type 7: Not-so-stubby area LSA<\/span><br \/>\n<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li>Created with redistribution within an NSSA<\/li>\n<li>Only send from ASBR<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>OSPF Link-State Database (LSDB) Each router stores it&#8217;s LSA in it&#8217;s LSDB. Each router within the same area should have the same LSDB information. SPF algortithm for each area it is connected to. The router thinks it&#8217;s the root of the tree and draws branches via SPF LSAs in OSPF LSDB are pieces that the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[14,8],"tags":[],"class_list":["post-48","post","type-post","status-publish","format-standard","hentry","category-ospf","category-route"],"_links":{"self":[{"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/posts\/48","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/comments?post=48"}],"version-history":[{"count":0,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/posts\/48\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/media?parent=48"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/categories?post=48"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/tags?post=48"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}