{"id":226,"date":"2024-12-12T22:56:54","date_gmt":"2024-12-13T05:56:54","guid":{"rendered":"https:\/\/eisaichen.com\/?p=226"},"modified":"2025-04-07T12:55:04","modified_gmt":"2025-04-07T19:55:04","slug":"fix-poor-network-performance-when-using-hyper-v-external-network-with-wi-fi-adapter","status":"publish","type":"post","link":"https:\/\/eisaichen.com\/?p=226","title":{"rendered":"Fix poor network performance when using Hyper-V external network with Wi-Fi adapter"},"content":{"rendered":"\n

If you bridge a Wi-Fi adapter to Hyper-V as I do<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

You may notice a significant drop in upload speed, which makes it difficult to transfer any file out of your computer. This has an effect on the host and your VMs.<\/p>\n\n\n\n

More precisely, is the retransmission rate skyrockets, your NIC needs to retransmit many times to send a single packet out.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

To fix this, we simply need to disable all offload features for our virtual network adapter.
Is the virtual network adapter on host, NOT the physical network adapter.<\/strong>
You don’t need to change any thing for your physical network adapter.<\/p>\n\n\n\n

Fix for Host and Windows VMs<\/h2>\n\n\n\n

For example, the wifi adapter I use for Hyper-V is
Intel(R) Wi-Fi 6E AX211 160MHz<\/kbd><\/code>
And the associate virtual network adapter is
Hyper-V Virtual Ethernet Adapter #3<\/kbd><\/p>\n\n\n\n

You can check it by using this command
Get-NetAdapter<\/code><\/p>\n\n\n\n

Next, open Device Manager<\/kbd> and open the properties of your virtual NIC<\/strong>, open tab “Advanced”<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Disable the following options:<\/p>\n\n\n\n

Large Send Offload V1 (IPv4)   # If exist\nLarge Send Offload V2 (IPv4)\nLarge Send Offload V2 (IPv6)<\/code><\/pre>\n\n\n\n
# powershell\n\nGet-NetAdapter<\/code>\nSet-NetAdapterAdvancedProperty -Name \"vEthernet (Hyper-V Wi-Fi)\" -RegistryKeyword \"*LsoV1IPv4\" -RegistryValue \"0\"\nSet-NetAdapterAdvancedProperty -Name \"vEthernet (Hyper-V Wi-Fi)\" -RegistryKeyword \"*LsoV2IPv4\" -RegistryValue \"0\"\nSet-NetAdapterAdvancedProperty -Name \"vEthernet (Hyper-V Wi-Fi)\" -RegistryKeyword \"*LsoV2IPv6\" -RegistryValue \"0\"<\/code><\/pre>\n\n\n\n
That’s it, Your wifi performance should now be back to normal.<\/p>\n\n\n\n
Fix for Linux VMs<\/h2>\n\n\n\n
Create a script file with the following code
\/usr\/local\/sbin\/disable-offloading.sh<\/kbd><\/p>\n\n\n\n
#!\/bin\/bash\n\n# Change this to your virtual NIC that is using hosts wifi\nINTERFACE=\"eth0\"\n\nethtool -K $INTERFACE tso off<\/code><\/pre>\n\n\n\n
Run it<\/p>\n\n\n\n
sudo chmod +x \/usr\/local\/sbin\/disable-offloading.sh\nsudo \/usr\/local\/sbin\/disable-offloading.sh<\/code><\/pre>\n\n\n\n
And now your VM should have full performance with wifi.<\/p>\n\n\n\n
\"\"<\/figure>\n\n\n\n
If you want to auto run the script on system starts, you can use rc.local<\/kbd> file<\/p>\n\n\n\n
echo '#!\/bin\/bash -e' >> \/etc\/rc.local\necho '\/usr\/local\/sbin\/disable-offloading.sh' >> \/etc\/rc.local\nsudo chmod +x \/etc\/rc.local<\/code><\/pre>\n\n\n\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
If you bridge a Wi-Fi adapter to Hyper-V as I do You may notice a significant drop in upload speed, which makes it difficult to transfer any file out of your computer. This has an effect on the host and your VMs. More precisely, is the retransmission rate skyrockets, your NIC needs to retransmit many […]<\/p>\n","protected":false},"author":1,"featured_media":227,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-226","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/eisaichen.com\/index.php?rest_route=\/wp\/v2\/posts\/226","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/eisaichen.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/eisaichen.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/eisaichen.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/eisaichen.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=226"}],"version-history":[{"count":5,"href":"https:\/\/eisaichen.com\/index.php?rest_route=\/wp\/v2\/posts\/226\/revisions"}],"predecessor-version":[{"id":250,"href":"https:\/\/eisaichen.com\/index.php?rest_route=\/wp\/v2\/posts\/226\/revisions\/250"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/eisaichen.com\/index.php?rest_route=\/wp\/v2\/media\/227"}],"wp:attachment":[{"href":"https:\/\/eisaichen.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=226"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/eisaichen.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=226"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/eisaichen.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=226"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}