Hi,
With High sierra and Mac Book Pro 2013, I have, everyday, problems to connect Internet (WIFI OK) : I have found the problem : by cancelling all the DNS addresses in the WIFI rules, connection is good!
But everyday, I must make that!
Sorry for my english language (french)...
thanks in advance
Paul
MacBook Pro with Retina display, OS X Mavericks (10.9)
Check for Wi-Fi issues using your Mac
You can also try starting up into safe mode and see if the issue persists and testing on another user account:
Use safe mode to isolate issues with your Mac
How to test an issue in another user account on your Mac
Let me know how this goes.
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Have a great day!
The DNS server settings can come from 2 places
Look in the System Preferences > Network > Advanced tab, DNS to view the servers. Once the panel is unlocked you can tell which source set the servers…
1. If the router supplies some default DNS servers the setting on OS X will be grey.
2. If the DNS servers are set manually the text will be black.
I'd consider manually adding a different set of DNS servers as a test - try Googles DNS servers, 8.8.8.8 and 8.8.4.4
Or find ones from OpenDNS.org or http://quad9.net/
Save the settings & see if the internet works.
This has some info on DNS
http://osxdaily.com/2015/12/05/change-dns-server-settings-mac-os-x/
Besides just changing them, SOMETIMES it's required to flush the cache too.
http://osxdaily.com/2017/03/08/clear-dns-cache-macos-sierra/
You can also enter them in terminal as well, an example:
networksetup -setdnsservers Wi-Fi 8.8.8.8 8.8.4.4
dns problems
