{"id":14457,"date":"2013-04-10T08:06:20","date_gmt":"2013-04-10T07:06:20","guid":{"rendered":"https:\/\/aidanfinn.com\/?p=14457"},"modified":"2013-04-10T08:06:20","modified_gmt":"2013-04-10T07:06:20","slug":"kb2823958-virtual-switch-extension-cant-send-packets-separately-through-each-nic-in-ws2012-hyper-v","status":"publish","type":"post","link":"https:\/\/aidanfinn.com\/?p=14457","title":{"rendered":"KB2823958 &#8211; Virtual Switch Extension Can\u2019t Send Packets Separately Through Each NIC In WS2012 Hyper-V"},"content":{"rendered":"<p>A lot of posts appeared last night that WS2012 Hyper-V admins might want to pay attention to.&#160; This <a href=\"http:\/\/support.microsoft.com\/kb\/2823958\" target=\"_blank\">one<\/a> deals with a situation where virtual switch extension cannot send packets separately through every individual network adapter in Windows Server 2012.<\/p>\n<blockquote>\n<p><strong><u>Symptoms<\/u><\/strong><\/p>\n<p>Consider the following scenario: <\/p>\n<ul>\n<li>You have a virtual switch extension installed on a Windows Server 2012-based Hyper-V server. <\/li>\n<li>The extension sends packets that contain one or more of the following flags:&#160;\n<p>NDIS_SEND_FLAGS_SINGLE_QUEUE          <br \/>NDIS_SEND_FLAGS_SWITCH_DESTINATION_GROUP           <br \/>NDIS_SEND_FLAGS_SWITCH_SINGLE_SOURCE           <br \/>NDIS_SEND_COMPLETE_FLAGS_SINGLE_QUEUE           <br \/>NDIS_SEND_COMPLETE_FLAGS_SWITCH_SINGLE_SOURCE           <br \/>NDIS_RECEIVE_FLAGS_SINGLE_VLAN           <br \/>NDIS_RECEIVE_FLAGS_SINGLE_QUEUE           <br \/>NDIS_RECEIVE_FLAGS_SINGLE_ETHER_TYPE           <br \/>NDIS_RECEIVE_FLAGS_SWITCH_DESTINATION_GROUP           <br \/>NDIS_RECEIVE_FLAGS_SWITCH_SINGLE_SOURCE           <br \/>NDIS_RETURN_FLAGS_SINGLE_QUEUE           <br \/>NDIS_RETURN_FLAGS_SWITCH_SINGLE_SOURCE<\/p>\n<\/li>\n<\/ul>\n<p>In this scenario, the packets are sent by using the same network adapter in the virtual network.<\/p>\n<p><strong><u>Cause<\/u><\/strong><\/p>\n<p>This issue occurs because Network Driver Interface Specification (NDIS) chains the Net Buffer Lists (NBLs) incorrectly.<\/p>\n<\/blockquote>\n<p>A supported <a href=\"http:\/\/support.microsoft.com\/hotfix\/KBHotfix.aspx?kbnum=2823958\" target=\"_blank\">hotfix<\/a> is available from Microsoft.<\/p>\n<div id=\"scid:0767317B-992E-4b12-91E0-4F059A8CECA8:4233166b-91f2-4a45-b254-ce0e36b7d2b1\" class=\"wlWriterEditableSmartContent\" style=\"float: none; padding-bottom: 0px; padding-top: 0px; padding-left: 0px; margin: 0px; display: inline; padding-right: 0px\">Technorati Tags: <a href=\"http:\/\/technorati.com\/tags\/Windows+Server+2012\" rel=\"tag\">Windows Server 2012<\/a>,<a href=\"http:\/\/technorati.com\/tags\/Hyper-V\" rel=\"tag\">Hyper-V<\/a>,<a href=\"http:\/\/technorati.com\/tags\/Virtualisation\" rel=\"tag\">Virtualisation<\/a>,<a href=\"http:\/\/technorati.com\/tags\/Networking\" rel=\"tag\">Networking<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"<p>A lot of posts appeared last night that WS2012 Hyper-V admins might want to pay attention to.&#160; This one deals with a situation where virtual switch extension cannot send packets separately through every individual network adapter in Windows Server 2012. Symptoms Consider the following scenario: You have a virtual switch extension installed on a Windows &hellip; <a href=\"https:\/\/aidanfinn.com\/?p=14457\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;KB2823958 &#8211; Virtual Switch Extension Can\u2019t Send Packets Separately Through Each NIC In WS2012 Hyper-V&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[20],"tags":[181,80,195,118],"class_list":["post-14457","post","type-post","status-publish","format-standard","hentry","category-hyper-v","tag-hyper-v","tag-networking","tag-virtualisation","tag-windows-server-2012"],"aioseo_notices":[],"jetpack_featured_media_url":"","amp_enabled":true,"_links":{"self":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/posts\/14457","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=14457"}],"version-history":[{"count":0,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=\/wp\/v2\/posts\/14457\/revisions"}],"wp:attachment":[{"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=14457"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=14457"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/aidanfinn.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=14457"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}