Q: OSX Yosemite Wifi issues

I meant to point out in my last post that I am a UK BT customer too - are you using HomeHub5? Do you know how to check if you have the latest firmware?  All my iOS devices worked when my MBPro couldn't connect to 5ghz

Hi Simen

"I only use Tomato or OpenWRT compatible routers."

Could you name/specify  the routers you use?

Thanks. Paul

Hi PJF30, If I'm correct, Tomato, OpenWRT or DD-WRT compatible routers are routers that can be flashed to these alternative firmware versions. If properly flashed, these will allow Greenfield mode on these routers to be switched off and GF-BRCM mode to be chosen instead, so as to better accomodate the Broadcom card in your Mac. Mixed Mode may show an improvement as well.

Thank you, Simen in this topic for this tip on page 194!

simenMar 25, 2015 11:06 AM
Re: OSX Yosemite Wifi issuesin response to simen

This made my 5GHz work to (got no IP before). If your router has the ability to disable Greenfield for GF-BRCM or Mixed Mode try that... Worked for ALL the machines on work so should work for you to.

simen wrote:

I discovered that Yosemite doesn't like "802.11n Preamble" set to Greenfield... Shouldn't be a problem usually, but looks like the drivers doesn't like it. So set it to "GF-BRCM" or "Mixed Mode". This might also fix 5GHz troubles (will test this at work where I have a 5GHz AP).

Before when I had to Greenfield I got 6/7 (TX/RX) Mbit, but now I get 144/144.

Before I figured this out I also found another "workaround" and that was to force the "Transmission Rate" to 54Mbit (better than 6), but that lead to a decrease of on my other N-devices that doesn't behave buggy.

Care to expand on the method of flashing firmware? Anyhow, I have a suspicion this may solve the issue with WPA Enterprise passwords as well.

Let me quote my summary on page 196 here:

Latest suspicion has been launched by forum member  "simen", who has definitely educated us to the existence of the WiFi preambles:Legacy, Mixed Mode, Greenfield, and GF-BRCM (Greenfield-Broadcom) (last 2 are "High throughput", +54 kbps  WiFi modes, probably supporting Jumbo Frames, not allowing anything except n-only WiFi networks, possible cause of some of the Yosemite WiFi troubles in combination with some WiFi routers ).

These questions then remain:

- does your router support Greenfield or Greenfield-Broadcom protocol?

- does your router support Jumbo Frames? ( this probably has to do with the already mentioned Maximum Transmission Unit being greater than 1450).- Setting MTU lower than 1450 has been known to work around the Yosemite WiFi bug in some cases.

-Is Greenfield colliding with GF-BRCM on some routers?

OK people, feel free to comment. Seems we will have to DIY here...

Caveat: in order to flash your router to a new firmware version, you really have to know what you are about.

As far as the Bluetooth and WiFi interference (on the 2.4 GHz band, of course) is concerned: if you are uncouth enough, you might try this Terminal command:

sudo defaults write /Library/Preferences/com.apple.airport.bt.plist bluetoothCoexMgmt Hybrid

This Hybrid Mode may be able to let Bluetooth and WiFi coexist on the same set of antennae/ the same Broadcom card. If you type in this command, you will have to issue your Admin/Root password as well. Thank you BushidoUK on page 17 of wifi keeps dropping since Yosemite upgrade for this tip!

There you are, 3 sets of variables to play with, all centered around your Broadcom card and antenna setup. And don't tell me this is getting complicated...  

PFJ30 wrote:

 

Hi Simen

"I only use Tomato or OpenWRT compatible routers."

Could you name/specify  the routers you use?

 

Thanks. Paul

DD-WRT: http://www.dd-wrt.com/site/support/router-database

OpenWRT: http://wiki.openwrt.org/toh/start#supported_hardware_-_router_type

When it comes to Tomato there are several "distros", my favorite and one of the most popular is Shibby:

http://tomato.groov.pl/?page_id=69

It would probably be easier to look for an option change the preamble in the default firmware since flashing could both brick your device if not careful and sometimes remove features. Or stick it out and wait for a fix from Apple, rumored in 10.10.3. That aside, flashing is both fun and educational, but it can be an expensive experience... The reward is high if you are successful though, leaving you A LOT of options to increase the usability of your router.

If you are venturing into these waters I would recommend OpenWRT > Tomato > DD-WRT (personal preferences).

hexdiy wrote:

 

Care to expand on the method of flashing firmware? Anyhow, I have a suspicion this may solve the issue with WPA Enterprise passwords as well.

Look at my answer above. Those links will lead you into the homepage of either DD-WRT, Tomato or OpenWRT. Those guides are better than anything I could come up with

I had just purchased a new MBP w/Retina 2014 which came preinstalled with OS X 10.10.2 , everything worked as it should except for the wifi.  I tried most of all the fixes listed for it with the exception of Kext Fix.  So deleting files, preferences, creating new location, several OS wipes nothing changed.

So I decided to look at my router which by default the wifi channel band frequencies are set to auto as they always have been.  Since I have no use for wireless a/b/g I set my 2.4 GHz to only do wireless N and my 5 GHz to AC mode only and also found a channel that was not interfering with other wifi signals in my area.  For me it was  for wireless N set to channel 2 and for wireless AC set to channel 44.  See attached photo.

Once I did this my wifi speeds were back to normal level's just like any other machine in my house.  Just to add to this I'm on Verizon Fios 150/150 also at my mothers house I have issues with the speeds being slow and she has Comcast Xfinity.  Cause wireless N I do not get my full speeds at all but pretty close to it.  On AC connection I get the full speeds of my connection.

Some might not know about Yosemite’s built-in WiFi diagnostics. Hold down the OPTION key while clicking on the WiFi icon in the menu bar and select Open Wireless Diagnostics...

The system will run a complete diagnostic routine and report on status. It will make suggestions on channel selection, interference, etc. You can also select the Scan option which will produce a list of nearby WiFi routers, what channels they are using, signal strength, what bandwidths are active, etc. This can be very useful in troubleshooting WiFi issues.

Hi

Just thought I'd share: I have had mixed results with this - I upgraded my Macbook Air (13", early 2014 revision) to Yosemite a couple of months back with no dramas (am using it now) or issues.  I thought I'd give it a go with my parents' iMac (27", late 2013 revision) which proved to be a disaster.  Upgraded ok, connected fine to the home Wi-Fi ok, but with zero Internet connectivity (with browsers and apps - but weirdly enough, Network Preferences did indicate I had Internet connectivity)

I tried all the proposed solutions (which I Googled) outlined in http://osxdaily.com/2014/10/25/fix-wi-fi-problems-os-x-yosemite/ (except for Reset SMC and the Unload & Reload discoveryd) - at one point I was able to browse for about 3 minutes and then it disappeared.

All I can say is - thank god for Time Machine!!!  Restored everything back to Mavericks and will await a REAL solution before attempting another upgrade.

I have Macbook pro 13 mid 2009 and I installed Yosemite shortly after reveal. Everything was fine until the last update from apple when my Wifi connetivity became unusable. Interesting thing is my Firefox browser is loading normaly, but nothing else seems to be geting internet connectivity. I tried resseting smc pram and turning off firewall but nothing helped. Thethering from phone is working normaly, but through my wifi router not. All my other devices and PCs run same as always on the Wifi but my mac is wifi dead.

For Yosemite users having problems in large, enterprise wireless networks this is an interesting post : How does OSX 10.10.2 handle 802.11h Power Constraint Information Element

summary: There is a bug in Yosemite WRT to the Wi-Fi 802.11h standard. Even home users with advanced wireless AP's / routers with 802.11h Power Constraint (other terms like power balance might be used) enabled might benefit from turning this off.

IT might be even the case they suffer because neighbouring AP's have this feature enabled :-(

Deleting the some preferences files fixed it on my 2014 Macbook Pro Retina.  I was getting wifi drop-outs every 20 minutes, and every time I closed my Macbook's lid and/or put it to sleep.  Touch wood, not a single drop out in over 8 hours.

See Step 1 here:

http://osxdaily.com/2014/10/25/fix-wi-fi-problems-os-x-yosemite/

As those instructions say, remember to back up the files before you delete them.

1 of these files - 
com.apple.network.identification.plist - is missing on my mac.  Could that be my problem?  I tried removing the 4 others but that didn't help.  My issue seems to be somewhat different from others.  5Ghz works for me but my wireless printer doesn't support 5Ghz so it is a problem to print from my iOS devices.

No, I didn't see com.apple.network.identification.plist on my Macbook either.  So instead, I removed com.apple.network.eapolclient.configuration.plist, that being the closest match that I did have!

As ever, back them up first!!

When I do this the plist files seem to simply copy to the folder.  They do not move from their original folder.  Is that what is supposed to happen?

After you start dragging your files over, but before you drop them, hold down the Command key. That will modify your copy to be a move.