Yosemite keeps dropping WiFI connectivity

Question

After upgrading to Yosemite, my Macbook Air drops off the WiFi connection many times a day. The following ping test demonstrates that restarting WiFi leads to a successful reconnection.

$ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8): 56 data bytes
Request timeout for icmp_seq 0
Request timeout for icmp_seq 1
Request timeout for icmp_seq 2
Request timeout for icmp_seq 3
Request timeout for icmp_seq 4
Request timeout for icmp_seq 5
Request timeout for icmp_seq 6   (Turn Wifi Off, Turn Wifi On)
Request timeout for icmp_seq 7
Request timeout for icmp_seq 8
Request timeout for icmp_seq 9
Request timeout for icmp_seq 10
Request timeout for icmp_seq 11
Request timeout for icmp_seq 12
Request timeout for icmp_seq 13
64 bytes from 8.8.8.8: icmp_seq=14 ttl=49 time=68.005 ms
64 bytes from 8.8.8.8: icmp_seq=15 ttl=49 time=203.014 ms
64 bytes from 8.8.8.8: icmp_seq=16 ttl=49 time=227.464 ms

Why does Yosemite keep dropping Wifi? Mountain Lion was working great. My iPhone is connects to the same Wifi network without a problem.

Answer 1

This isn't a solution, and it isn't a definitive answer, but WiFi/Bluetooth issues have been reported by many users (including yours truly) of OS X Yosemite. Apple is reportedly working on a fix, which may or may not help all of these users.

Answer 2

I fixed this issue on my Early 2013 MBP on 10.10.4 by doing the following (lots of other stuff was tried first).

• Disable WiFi
• Open Finder
• Press Cmd+Shft+G to go to the folder /Library/Preferences/SystemConfiguration/
• Delete (or move) the following files:
  • com.apple.airport.preferences.plist
  • NetworkInterfaces.plist
  • preferences.plist
• Restart your computer
• Re-enable WiFi

Answer 3

I could be completely wrong with this, but I did have a time when an old 2010 Macbook would drop wifi and struggle to pick it up again.

My resolution was down to my router being both 2.4GHz and 5GHz with a "Smart Band" tech which would swap between bands for devices. Taking off this Smart Band feature and connecting to one specific band did resolve my issue. It may not be the answer, but could be worth a try :)

Answer 4

thanks doublesharp. I have three macs that are continually dropping the WiFi connection - all running Yosemite and one of them being a BRAND NEW 5 day old Macbook. I deleted the files you recommended and the Wireless Diagnostics app (spotlight will find it) now runs without registering dropouts every few minutes. If this continues to work for another hour I will do the same on both my other Macs.

I do have to say that Yosemite is absolutely the WORST Mac operating system I have ever experienced. And I started with Jaguar! Steve would say "it just doesn't work".

5 minutes later: I opened Skype and the Macbook dropped the Wifi Connection...

Answer 5

Troubleshooting WiFi connectivity is one of the more frustrating issues I deal with personally/professionally.

For people looking for assistance (and the OP if the issue still persists), you will want to isolate things and gather data.

1. Use Wireless Diagnostics to capture and analyze the wireless network - both before you have a problem, during the problem, and after the problem.
2. Get a piece of paper to diligently write down the details in your WiFi icon when you option click it: (all the data can be relevant, but focus on BSSID, Tx Rate and Channel initially. Once you have 10 data points, you can narrow down what's happening between your Mac and your WiFi router.
   
3. You may need to capture WiFi logs and sysdiagnose to collect the precise reason why WiFi dropped and when. You may need engineering help to analyze these logs.

In the case above, the ping is a poor tool to tell WiFi issues. Not only does WiFi have to work, the IP addresses need to be working, DNS needs to be working, the upstream link needs to be working, the routing (BGP/whatever) that your ISP has configured needs to be working. Basically, If you can't call a number across the country - rather than focusing on no answer, you can focus on if your Phone is connected to the wall jack.

If you can ping a device on your local network (the router number above 10.0.10.1) would be way better to see if WiFi is viable rather than pinging 8.8.8.8 which lies far outside your control of the local network.

If anyone wants to dig into their data, post a new question with the details above and @bmike me in the comments here. I often like to help dive into this sort of issue once the data has been collected or there's a chance to get to the data to know what's happening.

If you don't want to collect the data to nail down why your disconnects are happening (and how often it really happens), here are other things you can try:

1. Get off 2.4 GHz - use 5 GHz as it's far less susceptible to interferance and channel overlap.
2. If you are on 2.4 - get a tool like WiFi Explorer to make sure you have a viable environment to have a reliable experience.
3. If you want to learn more and have limited time to piece things together from internet volunteers, this take control book by Glenn Fleishman is excellent.

Answer 6

Mgmt summary: Seems fixed now, finally, in Monterey. (That looked like the perfect reason to answer a 7 year old question to me...)

I happened to service a Macbook Air that was almost impossible to use, wifi disconnecting every 5 seconds; only when I turned off bluetooth, the wifi would work. Tried several other fixes (resetting bluetooth, defaults write ...../com.apple.airport.bt.plist, and so on), but none of them worked. At all. But with bluetooth off: perfect wifi.

Then I upgraded the Macbook, first to Big Sur (wifi still not working with bluetooth on), then to Monterey and suddenly BT and Wifi seem to be able to co-exist. N=1, so YMMV.