{"action":"created","issue":{"url":"https://api.github.com/repos/nodemcu/nodemcu-firmware/issues/715","labels_url":"https://api.github.com/repos/nodemcu/nodemcu-firmware/issues/715/labels{/name}","comments_url":"https://api.github.com/repos/nodemcu/nodemcu-firmware/issues/715/comments","events_url":"https://api.github.com/repos/nodemcu/nodemcu-firmware/issues/715/events","html_url":"https://github.com/nodemcu/nodemcu-firmware/issues/715","id":114418556,"number":715,"title":"Unable to send multicast UDP packets","user":{"login":"xhs","id":10380759,"avatar_url":"https://avatars.githubusercontent.com/u/10380759?v=3","gravatar_id":"","url":"https://api.github.com/users/xhs","html_url":"https://github.com/xhs","followers_url":"https://api.github.com/users/xhs/followers","following_url":"https://api.github.com/users/xhs/following{/other_user}","gists_url":"https://api.github.com/users/xhs/gists{/gist_id}","starred_url":"https://api.github.com/users/xhs/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/xhs/subscriptions","organizations_url":"https://api.github.com/users/xhs/orgs","repos_url":"https://api.github.com/users/xhs/repos","events_url":"https://api.github.com/users/xhs/events{/privacy}","received_events_url":"https://api.github.com/users/xhs/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":2,"created_at":"2015-10-31T16:06:03Z","updated_at":"2015-11-19T03:12:04Z","closed_at":null,"body":"I'm trying to implement mDNS in Lua.\r\n\r\nWith the information I got from [Issue 398](https://github.com/nodemcu/nodemcu-firmware/issues/398) and [nodemcu-ssdp](https://github.com/pastukhov/nodemcu-ssdp), I can now receive and parse mDNS queries successfully. But I am unable to send response to the multicast address (224.0.0.251).\r\n\r\nHere's the testing code:\r\n```lua\r\nwifi.setmode(wifi.STATION)\r\nwifi.sta.config('ssid', 'password')\r\nip = wifi.sta.getip()\r\nprint(ip)\r\nnet.multicastJoin(ip, '224.0.0.251')\r\nsock = net.createConnection(net.UDP, 0)\r\nsock:connect(5353, '224.0.0.251')\r\nsock:send('test broadcast', function() print('Sent') end)\r\n```\r\n\r\nI can see \"Sent\" printed but get nothing in Wireshark.\r\n\r\nTested on master branch and dev branch.\r\n\r\nIs there anything I should do before sending multicast packets?\r\nOr does NodeMCU support this at all?\r\n"},"comment":{"url":"https://api.github.com/repos/nodemcu/nodemcu-firmware/issues/comments/157935353","html_url":"https://github.com/nodemcu/nodemcu-firmware/issues/715#issuecomment-157935353","issue_url":"https://api.github.com/repos/nodemcu/nodemcu-firmware/issues/715","id":157935353,"user":{"login":"nanikjava","id":883406,"avatar_url":"https://avatars.githubusercontent.com/u/883406?v=3","gravatar_id":"","url":"https://api.github.com/users/nanikjava","html_url":"https://github.com/nanikjava","followers_url":"https://api.github.com/users/nanikjava/followers","following_url":"https://api.github.com/users/nanikjava/following{/other_user}","gists_url":"https://api.github.com/users/nanikjava/gists{/gist_id}","starred_url":"https://api.github.com/users/nanikjava/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/nanikjava/subscriptions","organizations_url":"https://api.github.com/users/nanikjava/orgs","repos_url":"https://api.github.com/users/nanikjava/repos","events_url":"https://api.github.com/users/nanikjava/events{/privacy}","received_events_url":"https://api.github.com/users/nanikjava/received_events","type":"User","site_admin":false},"created_at":"2015-11-19T03:12:04Z","updated_at":"2015-11-19T03:12:04Z","body":"I've tested this on my ESP12E DevKit 1.0 with the following firmware\r\n\r\nNodeMCU 0.9.6 build 20150704  powered by Lua 5.1.4\r\n\r\nand I can't see it in Wireshark too. When I use Linux machine to multicast using the command\r\n\r\niperf -c 224.0.0.251 -u -T 32 -t 3 -i 1\r\n\r\nI can see it in Wireshark.\r\n\r\nIs this a bug ?\r\n"}}