Originally Posted By: pbGuy
Since updating to 10.10.4, I am now experiencing intermittent internet connectivity issues (both LAN & WiFi) after putting my MBP to Sleep. Upon reawakening, I have to Restart in order to regain internet connectivity.

My wife was having a similar issue with 10.10.3 on her Mac mini but my Mac mini running 10.10.4 Public Beta along with various iPhones, iPads, Apple TVs, and wireless printers were having no problems at all. Her problem was solved when we
  1. shut her Mac mini down
  2. Powered the router down
  3. Powered the cable modem down
  4. paused five minutes
  5. Powered up the modem and waited for it to settle
  6. Powered up the router and waited for it to settle
  7. powered up her Mac mini
Since then she has had no connection problems, and there are still no connection problems with the various other devices on the network.

I don't know that the shutdown order was important but I do believe the restart sequence and giving each device time to "settle" before restarting the next device can be critical. FWIW the solid connection has continued since she installed the release version of 10.10.4.

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