{"id":1053,"date":"2023-11-20T11:48:20","date_gmt":"2023-11-20T09:48:20","guid":{"rendered":"https:\/\/valentijn.sessink.nl\/?p=1053"},"modified":"2023-11-20T11:48:20","modified_gmt":"2023-11-20T09:48:20","slug":"homeassistant-network-mtu","status":"publish","type":"post","link":"https:\/\/valentijn.sessink.nl\/?p=1053","title":{"rendered":"HomeAssistant network MTU"},"content":{"rendered":"\n

I’m running HomeAssistant on a virtual PC, HAOS and all, but I’m using a tunnel that doesn’t have a 1500 bytes ethernet MTU. How to change the MTU?<\/p>\n\n\n\n\n\n\n\n

HomeAssistant (HA) on Home Assistant Operating System (HAOS) is a pretty slick and pretty well thought out system. The tight coupling between the domotica-part (HomeAssistant) and operating system (OS) part, HAOS, ensures that both keep running well, both are updatable from the web interface and both can be managed easily.<\/p>\n\n\n\n

The downside of this coupling is, that once you need specific OS settings, it isn’t always clear how to proceed. Home Assistant itself runs in a container, so you cannot change OS settings. Or can you? Turns out: yes, you can.<\/p>\n\n\n\n

Here is how to proceed.<\/p>\n\n\n\n

Connect a monitor and a keyboard to your HAOS installation. If it’s a virtual machine (like mine is), you just need to “connect” to the virtual display of the host machine. You will see:<\/p>\n\n\n\n

| |  | |                          \/\\           (_)   | |            | |  \n| |__| | ___  _ __ ___   ___     \/  \\   ___ ___ _ ___| |_ __ _ _ __ | |_ \n|  __  |\/ _ \\| '_ \\ _ \\ \/ _ \\   \/ \/\\ \\ \/ __\/ __| \/ __| __\/ _\\ | '_ \\| __|\n| |  | | (_) | | | | | |  __\/  \/ ____ \\\\__ \\__ \\ \\__ \\ || (_| | | | | |_ \n|_|  |_|\\___\/|_| |_| |_|\\___| \/_\/    \\_\\___\/___\/_|___\/\\__\\__,_|_| |_|\\__|\n\nWelcome to the Home Assistant command line.\n\nSystem information\n  IPv4 addresses for enp1s0: 192.168.112.170\/24\n  IPv6 addresses for enp1s0: fe80::cf78:914d:7da6:2265\/64\n\n  OS Version:               Home Assistant OS 11.1\n  Home Assistant Core:      2023.11.2\n\n  Home Assistant URL:       \nhttp[s]:\/\/......:8123\n  Observer URL:             \nhttp[s]:\/\/...:4357\nha ><\/code><\/pre>\n\n\n\n
On this HAOS prompt, type login<\/code><\/p>\n\n\n\n
You’ll now get a rather minimal “HAOS” Linux root prompt, just saying #. The “nmcli c<\/code>” command will tell you the name of your network interface:<\/p>\n\n\n\n
nmcli c\nNAME               UUID                                  TYPE      DEVICE \nSupervisor enp1s0  bf97b94b-9d4a-3728-9609-7ff76b1ae1a5  ethernet  enp1s0<\/code><\/pre>\n\n\n\n
The Supervisor enp1s0<\/code> link is the one you are looking for. View its MTU by typing nmcli con show 'Supervisor enp1s0'<\/code>, change it to 1234 by typing nmcli con modify 'Supervisor enp1s0' ethernet.mtu 1234<\/code>. This change will be saved automatically by NetworkManager, but it is not active immediately.<\/p>\n\n\n\n
Type nmcli c up 'Supervisor enp1s0'<\/code> to enable the new setting. Check the new setting with ip link list dev enp1s0<\/code>, it should say something like:<\/p>\n\n\n\n
2: enp1s0: mtu 1234 qdisc fq_codel state UP mode DEFAULT group default qlen 1000\nlink\/ether 98:fa:9b:05:16:ae brd ff:ff:ff:ff:ff:ff<\/code><\/pre>\n\n\n\n
To remove the new MTU, use nmcli c modify 'Supervisor enp1s0' ethernet.mtu \"\"<\/code>.<\/p>\n\n\n\n
Finally, type “exit” to quit the shell.<\/p>\n","protected":false},"excerpt":{"rendered":"
I’m running HomeAssistant on a virtual PC, HAOS and all, but I’m using a tunnel that doesn’t have a 1500 bytes ethernet MTU. How to change the MTU?<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[181,180,84,182],"class_list":["post-1053","post","type-post","status-publish","format-standard","hentry","category-happy-hacking","tag-home-assistant","tag-homeassistant","tag-mtu","tag-networking"],"_links":{"self":[{"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=\/wp\/v2\/posts\/1053","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1053"}],"version-history":[{"count":5,"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=\/wp\/v2\/posts\/1053\/revisions"}],"predecessor-version":[{"id":1059,"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=\/wp\/v2\/posts\/1053\/revisions\/1059"}],"wp:attachment":[{"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1053"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1053"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/valentijn.sessink.nl\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1053"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}