discoveryd process uses 100% CPU - Safari Can't find the server

On my home network I have two Macs: a 2013 MacBook Air and an 2008 MacPro. There are also usually a couple of iPhones and two iPads. There are also numerous non-computing devices.

The MacBook Air works perfectly. The iPads work perfectly. The iPhones seem to have intermittent doses of the discoveryd problem: good network connection but unable to find anything. Turning WiFi off and using the cellular network gets rid of the problem.

The MacPro has the discoveryd issue bad. Unlike most of the reports here it manifests when the computer is started up from cold. On most cold starts discoveryd will go to 100% CPU and no DNS lookups work for between 15 and 20 minutes. Then discoveryd starts working. Most days it keeps working all day but occasionally it will go bad during the day for a few minutes and then clear up.

I just thought it was worth reporting the variation on the theme. It seems this thing is a dog with fleas.

To all:

Interesting read on Ars - seems like the problem is discoveryd which replaced mDNSResponder in 10.10. Here is the article. Looks like you can replace with mDNSReposnder if you are brave or wait for Apple to fix discoveryd.

Add another victim to the discoveryd problem. I have even installed the 10.10.2 beta hoping for fix to no avail.

Add me too.

Same problem here at my Mac mini (Yosemite 10.10.1):

99% CPU load for discovery process and constantly growing memory consumption up to several GB

Solution: Uncheck "dynamical global hostname" at System - Sharing - Devicename and use local device name (e.g. mysupermac.local)

It might solve your problem but there are other issues : on my mac, the "dynamical global hostname" was not checked but I have the issue, and still have it. I guess several programs or situation are causing discoveryd to go crazy 😟

Dynamic global hostname was not checked on my computer either. Still looking and hoping for a fix. I'm even running 10.10.2 beta. I've pretty much had to stop using my desktop iMac.

The link in cwilmo's post of 2015 01/13 is bad. The correct link is:

http://arstechnica.com/apple/2015/01/why-dns-in-os-x-10-10-is-broken-and-what-yo u-can-do-to-fix-it/

(With the colons and slashes changed to "deactivate" it, the incorrect hidden link was to http <colon> <slash> <slash> http <slash slash> arstechnica.com/apple/2015/01/why-dns-in-os-x-10-10-is-broken-and-what-you-can- do-to-fix-it/)

I haven't read the linked article yet myself so can't comment on it.

This just started happening to me. Im trying to update Flash, it hangs on the download at 25% and I notice that discoverd starts to use over 100% CPU.

What is discoveryd? Should I cotinue to block its access?

I am running Yosemite 10.10.1 so there should not be a problem- but I am still having to block discoveryd oin the Norton Firewall until I get a definitive answer on whether discoveryd attempted connects from IP 224.0.0.251 and ff02::fb are valid.

I did something that seems to have "solved" the problem for now. I redirected all incoming DNS calls (ports 53) to my routers IP address using my routers port forwarding feature. I figure I could just let the router bounce the activity back. After doing that I am no longer getting flooded by DNS requests and my discoveryd activity is back to normal.

ok so i just plugged in my ethernet cord and the issue went away. Thankyou Lord lol. We'll see how long this lasts if it comes back you all will here from me.... Aside from pluggin in my ethernet cable for a few seconds i also turned off file sharing and did the terminal deal that someone posted and entered my password. I'm about to restart my CPU just to make sure things are in tact. I'm exstatict right now. my computer was overheating and everything. I even purchased a new battery. The old one was done regardless it was that time lol. So here we go i'm gonna run Logic X and hope for the best. Thanks everyone for your posts helped me trouble shoot seems the discoveryd is a wireless network issue.

wireless works fine also.... before doing this i had an "!" in my wireless icon also

so that lasted about 10 mins smh.... so now that im paying attention to my activity monitor in utilities kernel_task has been acting kind of shady as well smh HELPPPPPP!!!