“You may have seen or heard the growing disquiet about Yosemite and Wi-Fi. Like me, you may even be affected,” Paul Ducklin reports for Naked Security. “No-one seems to know what’s wrong, and without a scientific explanation it’s hard to know where to lay the blame.”

“Yosemite itself could have introduced a bug; or your hardware might be affected by a reliability problem that simply didn’t show up before; or some third-party software might be revealing a latent flaw,” Ducklin reports. “The symptoms are varied, but the most commonly reported problem is pretty much what I’ve experienced since first rebooting into OS X 10.10 and going online wirelessly. Your network works fine for a while, typically between about 30 seconds and five minutes, and then fairly abruptly begins to suffer almost total traffic loss. The network shows up as active, and low-level packets such as PINGs can be sent and received as normal. But traffic such as UDP and TCP just doesn’t get through. So you can’t use DNS.”

“We’re not going to blame Yosemite yet, but we are turning to the Naked Security community for fixes, workarounds or even bodges,” Ducklin reports. “What’s your bodge?”

Read more in the full article here.

MacDailyNews Take: This is not a new issue. It also happened with OS X Mavericks. We had this problem on one of our Macs running OS X Yosemite and fixed it the way we always have, by resetting the SMC (System Management Controller).

We don’t know precisely why this works, only that it has worked for us in multiple cases of wonky Wi-Fi with iMacs and MacBook Airs running OS X Mavericks and OS X Yosemite.

Resetting the System Management Controller (SMC)

Resetting the SMC on portables with built-in batteries:
1. Shut down the computer.
2. Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
4. Release all the keys and the power button at the same time.
5. Press the power button to turn on the computer.

Resetting the SMC on Mac portables with a battery you can remove:
1. Shut down the computer.
2. Disconnect the MagSafe power adapter from the computer, if it’s connected.
3. Remove the battery.
4. Press and hold the power button for 5 seconds.
5. Release the power button.
6. Reconnect the battery and MagSafe power adapter.
7. Press the power button to turn on the computer.

Resetting the SMC for Mac Pro, Intel-based iMac, Intel-based Mac mini, or Intel-based Xserve:
1. Shut down the computer.
2. Unplug the computer’s power cord.
3. Wait fifteen seconds.
4. Attach the computer’s power cord.
5. Wait five seconds, then press the power button to turn on the computer.

Note: Resetting the SMC does not reset, or otherwise change, the contents of PRAM, which is also known as NVRAM on Intel-based Macs.

[Thanks to MacDailyNews Reader “Ritt Padd” for the heads up.]