{"id":10468,"date":"2015-01-13T11:50:00","date_gmt":"2015-01-13T16:50:00","guid":{"rendered":"http:\/\/mjtsai.com\/blog\/?p=10468"},"modified":"2017-07-14T13:02:53","modified_gmt":"2017-07-14T17:02:53","slug":"why-dns-in-os-x-10-10-is-broken","status":"publish","type":"post","link":"https:\/\/mjtsai.com\/blog\/2015\/01\/13\/why-dns-in-os-x-10-10-is-broken\/","title":{"rendered":"Why DNS in OS X 10.10 Is Broken"},"content":{"rendered":"

Iljitsch van Beijnum<\/a>:<\/p>\n

\n

For 12 years, the mDNSResponder service managed a surprisingly large part of our Mac’s networking, and it managed this task well. But as of OS X 10.10, the mDNSResponder has been replaced with discoveryd, which does the same thing. Mostly. Here are some strange networking problems we’ve observed since installing 10.10[…]<\/p>\n

[…]<\/p>\n

If discoveryd isn’t doing its job properly, sometimes it helps to restart it. However, even this doesn’t always work, and restarting discoveryd gets old fast. If you’re not scared of a little command line hacking, there’s a better solution: you can reinstall the OS X 10.9 mDNSResponder on a 10.10 system. And after that, all the problems listed above magically go away.<\/p>\n<\/blockquote>\n

I wouldn’t do that<\/em>; go back to a full 10.9 system if 10.1 isn’t working for you.<\/p>\n

Update (2015-01-13): Paul Horowitz<\/a> on “How to Flush DNS Cache in OS X Yosemite with discoveryutil”.<\/p>\n

Update (2015-03-31): Craig Hockenberry<\/a>:<\/p>\n

Why isn’t there a tech note about all of these DNS issues in Yosemite? Does Apple not care? Or do they not know?<\/p><\/blockquote>\n

Chris Parker<\/a>:<\/p>\n

It’s known. And the teams care. Don’t know why there isn’t a reunite though.<\/p><\/blockquote>\n

Craig Hockenberry<\/a>:<\/p>\n

There are A LOT of people burning A LOT of cycles on this stuff. Communication would go a long way…<\/p><\/blockquote>\n

Update (2017-07-14): See also: Accidental Tech Podcast<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"

Iljitsch van Beijnum: For 12 years, the mDNSResponder service managed a surprisingly large part of our Mac’s networking, and it managed this task well. But as of OS X 10.10, the mDNSResponder has been replaced with discoveryd, which does the same thing. Mostly. Here are some strange networking problems we’ve observed since installing 10.10[…] […] […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"apple_news_api_created_at":"","apple_news_api_id":"","apple_news_api_modified_at":"","apple_news_api_revision":"","apple_news_api_share_url":"","apple_news_coverimage":0,"apple_news_coverimage_caption":"","apple_news_is_hidden":false,"apple_news_is_paid":false,"apple_news_is_preview":false,"apple_news_is_sponsored":false,"apple_news_maturity_rating":"","apple_news_metadata":"\"\"","apple_news_pullquote":"","apple_news_pullquote_position":"","apple_news_slug":"","apple_news_sections":"\"\"","apple_news_suppress_video_url":false,"apple_news_use_image_component":false,"footnotes":""},"categories":[2],"tags":[1143,131,728,31,904,30,903,476],"class_list":["post-10468","post","type-post","status-publish","format-standard","hentry","category-technology","tag-apple-software-quality","tag-bug","tag-domain-name-system-dns","tag-ios","tag-ios-8","tag-mac","tag-mac-os-x-10-10-yosemite","tag-networking"],"apple_news_notices":[],"_links":{"self":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/10468","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/comments?post=10468"}],"version-history":[{"count":4,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/10468\/revisions"}],"predecessor-version":[{"id":18326,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/10468\/revisions\/18326"}],"wp:attachment":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/media?parent=10468"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/categories?post=10468"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/tags?post=10468"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}