Q: OSX Yosemite Wifi issues

My wifi refuses to connect after waking from sleep. It will be connected for a few seconds (maybe 15) and then loses connection and keeps searching for it.  Our network is in the list, with the strongest signal.  But turning Airport on and off doesn't seem to do anything at all to help.  The best I've been able to do is wait for about 5 minutes until the thing stops TRYING to connect and the signal bars are all gray (disconnected).  Then select our network and it connects right up.  *very strange*

an ip address is a unique identifier made up of 4 octets to a device

IP's range from 000 to 255

so a typical private ip would be

192.168.0.1 (this is usually the routers address and can be written 192.168.000.001 as well as long as it is between 0 and 255

A subnet mask is a way to split up networks into separate sub networks and the usual subnet mask we all use is

255.255.255.0

what this means is the first 3 octets of the IP must match with whatever device they are trying to connect to, in this case

192.168.0

the last octet in the subnet mask (0) states that the last octet of the device IP can be anything from 1 to 254

so what happened to 0 and 255 for the last octet?

well 0 is the subnet itself and 255 is the broadcast address

so with a subnet mask of 255.255.255.0 you can have 254 devices using 192.168.0 for the first 3 octets

so why?

well if you want office 1 and office 2 to have access to corp stuff but not to each other on the same LAN (local area network) (your home or office) you split them up using subnet masks

so to split 192.168.0 into 2 networks you change the mask to

255.255.255.128

this means office 1 can have 126 devices and office 2 can have 126 devices all on the same lan but can't access each other

so office 1 IP's would be start 192.168.0.1 (0 is the subnet and 128 is the broadcast address)

and office 2 IP's would be start 192.168.0.130 (129 is the subnet and 255 is the broadcast address)

whats a broadcast?

every NIC (network interface card) broadcast out to the net who he is, in this case 192.168.0.2

the router (192.168.0.1) stores this info in a table and when another device (192.168.0.3) wants to connect to 192.168.0.2 it sends out a hello to 192.168.0.2 because you specified in the config your routers address 192.168.0.1 your router looks in its table and finds it and passes the data on from 192.168.0.3 to 192.168.0.2, if the router can't find 192.168.0.2 it will ask the next router it is attached to and so on until its gone through every router in the world and thats how data get sent around using ip address ,subnet mask and a router.

soon we are to run out of IPv4 which is why we need IPv6 and apple are using in prep for that but also because it encrypts traffic by default (i think) so it's fast and secure.

I've tried explaining this to everyone i work with but none of them get it straight off so i don't expect you guys too either or maybe I'm no good at teaching

I have a brand new (4 days old) rMBP/1TB/16Gb and I am so frustrated by this issue. It almost cost my company money for a trouble call from our network provider because many of us had this issue and we thought it was an issue with our ISP.  I mean new MacBooks couldn't possible fail like this (sigh)

I think I am going to have to roll back to day one and loose all of the data transferred and installed... Seriously crApple.... $3200 for this....

Anyway, Kevin, I tried your fix and it did speed things up, but I still have disconnect issues ( I am looking at a failed file download as I type this).  I have also tried the other suggestions regarding BT, etc.  Nothing has worked.

you don't need to run the nettop bit i only included that so you could see whats going on

it only needs to be turned off and on again,

its just 2 commands to run in the terminal window

networksetup -setv6off Wi-Fi

networksetup -setv6automatic Wi-Fi

just toggle your wifi on and off after each command to ensure it picks up the re-written configs

the issue seems to be DNS related so maybe setting your IPv4 to manual with DHCP and rebooting your router to clear it ARP cache may help

another issue that I had was duplicate share names so to cure it i changed my computer name under sharing so maybe that contributed to it

also if you open terminal, and your hostname is unknown that also points to DNS issues on the router

this is how i discovered the IPv6 problem by looking at the arp caches in terminal

arp -a (if you interested it shows the hostname and IP of what you have connected to recently)

but seeing as the initial build is wrong to start with who knows where to look for the many issues which is why i suggested running nettop in terminal to see if tcp6 was at the top your own net stack

to be sure there are no arp caches on routers and devices its always best to reboot everything after changing net configs on this dodgy build apple have given us

most home wifi issues are either DNS, ARP cache or domain related

you could always try setting IPv6 to manual from the preference network GUI

if you set it to link-local

then ok

then apply

go back into it and when the IPv6 address is there set it to manually

then ok

then apply

but best to reboot your wifi router and device to clear the caches otherwise it may pick up the old info

Just want to ensure that I'm on the record as yet another user suffering the same wireless connection issues following the yosemite update.   I've tried pretty much all the suggested solutions with no permanent success. (In fact I think things have degraded further as it's off line more frequently and for longer periods). Meanwhile I've dusted off my PC while I wait for apple to send out a fix.  Hurry please!

--T

Ok, so I did turn in my Apple Air Port Extreme IPV4 address configuration settings from "Using DHCP" to "Manual" and entered my i-Mac IP address. At first changed IPV6 from "Automatic" to "Link-local only" but quickly returned to "Automatic" because no improvements in WiFi performance. As I stated in previous post my WiFi is affected by multiple disconnections not during browsing or a lite computer use but during large files downloading, mainly movies or streaming movies to Apple TV via home sharing for a playback on my TV set. Also my WIFI is dropping during a speed test, specifically during upload test when using Speedtest.net. Well, after the above switch my movie streaming to Apple TV instead of dropping of several times went down to just a single disconnect during an entire show. At this point I'll wait for Apple and see if they are going to address this issue through the next update, however I'm not going to hold my breath for it. I'm afraid that at one point will have to replace my Apple router with a new one. I do not want to do it because all Apple devices not running Yosemite are performing beautifully. I do wish that I newer "upgraded" to Yosemite. Can't trust Apple on any of their initial software releases. Well, I learned my lesson once again. Thanks everyone for all suggestions.

Hi Kevin,

this is great reading. I am a developer, in an entirely different field of computing but always like to read about stuff I don't know in detail.

Been using the router and wifi for so many years and seen those names and numbers so many times and used them too ;-) But never bothered to de-compose them.. After reading you reply.. I thought, what the heck. Got me a cappuccino and a smoke and began reading. Very interesting.

One thing in your reply that caught me was Octets. In my field this refers to groups of 8. But in general terms can also refer to group.

The IP string is 4 groups... Am I correct in my assumption ?

Thanks for the write up ;-)

The matter of the fact is that, we are all here reseting network configs, playing with routers and all this other stuff....why?  For a company that builds computers and software around the whole "It just works" philosophy is just completely false. These WiFi issues are Yosemite's dealings.  They clearly have not tested this thoroughly before releasing it. If not that, then maybe they are all running in on the latest and greatest mac hardware...but either way, I'm really worried about Apple.  We have a half baked OS X that looks like a bad Linux Knock-off and still Wi-Fi issues.... Why can't we just go back to snow leopard days...where Apple actually took the time to release quality stuff.... no they are too busy trying to please all these teenagers dumbing them down in the "ease" of use.....

Christopher Starks wrote:

 

The matter of the fact is that, we are all here reseting network configs, playing with routers and all this other stuff....why?  For a company that builds computers and software around the whole "It just works" philosophy is just completely false. These WiFi issues are Yosemite's dealings.  They clearly have not tested this thoroughly before releasing it. If not that, then maybe they are all running in on the latest and greatest mac hardware...but either way, I'm really worried about Apple.  We have a half baked OS X that looks like a bad Linux Knock-off and still Wi-Fi issues.... Why can't we just go back to snow leopard days...where Apple actually took the time to release quality stuff.... no they are too busy trying to please all these teenagers dumbing them down in the "ease" of use.....

For the record. Snow Leopard is out-performed in any possible way by Yosemite, at least in regards to Audio, Video and other heavy-usage, at least to my knowledge.

We all play with routers today because something went wrong with 10.10 and without playing with routers we'd have internet trouble. Mistakes happen. And this thread is proof of it ;-)

Again this is to be expected with a brand new system or software. I have been using Macs since 1996. I have never seen a .0 release just working. Be that OS X or a software like Pro Tools. They all need a tweak here and there. And I don't mind such. Neither should those who choose to be the first to upgrade. Does it suck, yes. Is it perfect, NO. An exact reflection of the human being. Full of mistakes ;-)

These discussions must be hugely entertaining to the folks that monitor these threads at Apple. Watching their paying customers waving dead chickens, donning their lucky undies, not shaving until they've solved the issue (choose your own lucky charm) ... all in efforts to back-engineer an issue that Apple could surely just make a statement about ... something honest and transparent like "sorry folks it's broken and well fix it asap"

HI Morton

it refers to 8 bits which = 255 so four groups of 8 bits

so you can have 255 x 255 x 255 x 255 individual address's using IPv4 so quite a few

regards

Kev

maybe this is where they get all there ideas from...

a .0 should work out the door. And as for playing with routers?  I have moved 3 times in the last 8 years and have NEVER had to do anything with my router...ever... set it up 7 years ago and still working just fine...so no, incorrect.  Since Apple makes the hardware and software,, it is plausible that they should have seen these issues during their testing phase...unless they aren't using the same Macs we are buying...... In a windows world, I would understand this with all the different hardwares...but that uncertainty is pretty much moot with Apple. Outside of changing your battery, hdd and Ram....there's not that much difference to worry about......  As many problems as apple has had in the last few years (OS X Lion)  it's like they don't even test their crap, much like the gaming industry... it is known that they will release a Xbox game just to beat another company, knowing the product isn't finished... because with updates and DLC they can fix it and finish the game later.... Apple seems to be following through on this.... release the iOS version before OS X Yosemite? WHY? they went hand in hand....people could have waiting for Yosemite release to get iOS 8....  I highly doubt Apple Reps are using OS X Yosemite....can you imagine how things would be for them at the corporation level if they had these kind of issues? Dead.  They have to be running an older version, or some special version created specially for staff...it's not this crap that's for sure...

Kevin,

Thanks for the additional suggestions, however the disconnects are still happening.  I am just going to revert to day 1 (pre-yosimite) until they get this sorted out.  I cannot be wired everywhere I need to travel to.

Cheers,

Bill