Wifi Constantly Dropping in Lion

xhaduhm wrote:

I have a new mac mini with mountain lion and because I have several Macs, did not really pay attention to the wifi issue until I was spending more time using the mini. The wifi connection was constantly dropping. I have a cable modem router as well as a Cisco aironet access point. All of my Macs are connected to the Cisco access point but only the mini has mountain lion. After switching the mini to the ssid on the cable modem router, I have not experience the disconnection issues. I have not had time to look at the aironet access point settings but one size does not fit all in this case.

Do you have the most recent firmware installed in the Cisco router? This seems like an issue with the functions in the router since you could switch AP wireless endpoints and see the behavior improve. A lot of people seem to report that upgrading firmware was a solution for them. What security mode does each of your APs use? Is there a difference in supported modes, b/g/n and what you use?

eROCK1 wrote:

Mountain Lion is cool and all...but don't spend the money just because you think it will fix your WiFi issue. I upgraded to Mountain Lion, and STILL have the same WiFi issues as before. It's not a hardware issue because I bypassed my internal wireless card by installing a USB dongle, and still had the issue with the dongle. I spoke with the dongle manufacturer about it since all they deal with is WiFi, and they suggested that it could be a router issue or ISP related. Funny thing is, right next to my iMac is an HP laptop connected to the same wifi connection, and it doesn't have the drop outs. So it has something to do with OS X....just not sure WHAT part of OS X yet.

What indication of "WiFi issues" do you get? Are you just getting a message in your web browser that says "You are not connected to the Internet", or what? When the disconnected state is occuring, do you see "black bars" on your Airport indicator on the top right side of your screen, or do you see "gray bars" which indicate the WiFi connection is not up?

If you see black bars, then you are experiencing something at the higher levels of networking. If you open System Preferences->Networking, and then select you wireless adapter, and select "Advanced" and then go to the "DNS" tab, when you are connected or disconnected, do you see different DNS servers listed? If the list is not "empty" when you are disconnected, then you probably need to remove the rogue entries in that list.

To update my issues, things were running ok for the last couple of months and the issue started to return. I just ended up hardwiring and giving up.

To answer the quesion phonei has been asking, when I have/had drops the WiFi indictor would always switch from black to grey. When drops happen every 2 minutes, which can happen, it turns grey every time.

I have managed to get it working for fairly long periods of time running through fixes in this thread. The problem is it will just randomly return.

Mentioned before, but it's a late model 2011 iMac running 10.7.5 at this point. Problems started when I first updated to Lion from Snow Leopard.

torndownunit wrote:

...

I have managed to get it working for fairly long periods of time running through fixes in this thread. The problem is it will just randomly return.

This kind of random behavior, is often attributable to interference coming from another device. Are you using 2.4ghz? If so, a baby monitor, or wireless phone, or VCR Rabbit type device. I bought one of the X10.com advertised wireless video sender/receiver pairs, and it just killed my 2.4ghz network in the house. If it's random, then perhaps a neighbor is turning something like this on, and it's affecting your wireless signal. If you are on 2.4ghz, what channel are you using? Did you try 1, 6 and 11 each in turn for a long enough period of time to note whether one channel was more likely to fail? Also, if you can find some wireless network analysis tools (mountain lion has some in it), that might let you see whether or not there is enough other WiFi traffic, that it's just so many people around you that the signals are being interferred with.

The problem is there are no new devices in the house, no new wireless networks in the area, and nothing else that has changed in the time I have had these problems. I have switched channels, and that was one of the fixes that helped for short time periods. Eventually, the issue would return though.

I have been with this thread since the early days, so trust me channel switching was one of the first things I tried. I also tried an Aiport Extreme during all of this to test what would happen, and it had the same issues eventually as well.

During this time there has not been a single other issue with any wirless devices in the house. There are phones, laptops, tablets that use the network with no issue.

You might have missed my earlier report, but I'll summarize it here.

My MacPro and Macbook would lose Internet connection 1-2 time each day ("... You are not connected to the Internet..."). The MacBook uses WiFi to my Cisco router, but the MacPro is Ethernet hardwired to the router. Made no difference ,,, both would lose connectivity. And like you, my Windows machine as well as FOSCAM cameras, 2 iPhones, an iPad, a Roku, Apple TV, a BlueRay player ... all were OK.

Well the problem got fixed 2 months ago, although by accident. My cable MODEM was behaving poorly and Brighthouse exchanged it out for a newer model. My Internet access speed went up by 5X to where it should have been.

I haven’t had the problem since. So why does changing the MODEM fix the problem?

It is some form of timeout action. It may be those apps which periodically communicates over the Internet to gather data; mail queries are a good example. I suspect that if the Internet connection is even slightly degraded and these apps get “upset” waiting for a reply, they notify some extension of the OSX that, in turn, pulls the Internet plug.

You might do some diagnostics on your throughput with your ISP or try logging on via another WiFi network where people are not experiencing these drop-outs.

Regards

torndownunit wrote:

The problem is there are no new devices in the house, no new wireless networks in the area, and nothing else that has changed in the time I have had these problems. I have switched channels, and that was one of the fixes that helped for short time periods. Eventually, the issue would return though.

I have been with this thread since the early days, so trust me channel switching was one of the first things I tried. I also tried an Aiport Extreme during all of this to test what would happen, and it had the same issues eventually as well.

During this time there has not been a single other issue with any wirless devices in the house. There are phones, laptops, tablets that use the network with no issue.

Okay, I'm not asking if you did your homework or anything like that. I'm just trying to figure out which things you have tried and what the results were. It still sounds to me like somewhere around you there is a 2.4ghz interferring signal. When you tried the Airport Extreme, did you try 5ghz? If you did check with 5ghz what was the results of that?

Results were the same. Obviously using the Airport, I did give 5ghz a try. And as with the previous router, tried a variety of channels with it. As with other setups, no other devices including another Mac latop running Snow Leopard had any issues with any of the network experimentations to try to fix the problem. Just the iMac. Any 'fix' was just temporary on that machine. But, with it hardwired it's fine, so it's staying that way.

Again, there are only 2 other networks in my area, and no new devices in the house broadcasting since I was using my Macbook. There is no more interference than there ever was, which is very little. The network was the same when I got the iMac, and it was the only device that had issues. I switched to an Aiport Extreme to see what would happen, the results were still the same. Along with trying every other tip in this thread as well. There was no problem up until I started using this iMac. And there still is no problem using any other devices.

Okay if the airport bars are going grey, then something in the RF environment is whacked out. Were you able to use the instructions for turning on "debug" logging? If you do that, you might find some interesting details in the wifi logging.

Look at this page in particular:

http://prowiki.isc.upenn.edu/wiki/Enabling_Advanced_Logging_for_Wireless_in_Mac_ OS_X

UPenn was involved with Apple in trying to resolve the problem for their students, so stuff on their Wiki might be very imformative.

Factually: if iPhones and iPad work well, RF pollution alone can not be the root cause.

I have the same issue at home; all my devices worked perfectly (2 iPad, iPhone, Squeezebox, Wii, Mac on Lion, Mac on Snow Leopard). The Macbooks work perfectly with WiFi and Bluetooth.

Now I upgraded the Snow Leopard MacBook to Mountain Lion and it is the only machine to experience the problem. It has issues with both WiFi and Bluetooth.

Of course, I also thought about RF problems. I performed a site survey and my wifi is clean; all AP's use different and non-overlapping channels; signal strength is also good. All other devices in the house keep working well (especially my Wife's mac that uses BT and WiFi).

It seems to be that the Bluetooth (which other threads mention) and WiFi (this thread) issues are stemming from different root causes that are not (just) RF related. Maybe software only or hardware+software related but point in case, this is *only* an ML issue.

It is therefore hard to blame the environment even if tempting.

Oh, Freddy.

TotallyFred wrote:

Factually: if iPhones and iPad work well, RF pollution alone can not be the root cause.

I have the same issue at home; all my devices worked perfectly (2 iPad, iPhone, Squeezebox, Wii, Mac on Lion, Mac on Snow Leopard). The Macbooks work perfectly with WiFi and Bluetooth.

Now I upgraded the Snow Leopard MacBook to Mountain Lion and it is the only machine to experience the problem. It has issues with both WiFi and Bluetooth.

Of course, I also thought about RF problems. I performed a site survey and my wifi is clean; all AP's use different and non-overlapping channels; signal strength is also good. All other devices in the house keep working well (especially my Wife's mac that uses BT and WiFi).

It seems to be that the Bluetooth (which other threads mention) and WiFi (this thread) issues are stemming from different root causes that are not (just) RF related. Maybe software only or hardware+software related but point in case, this is *only* an ML issue.

It is therefore hard to blame the environment even if tempting.

Okay, without a spectrum analyzer you will not be able to see all RF that is present. Sure, you can see "wifi" or "bluetooth" or other "standards", but proprietary things like wireless telephones, VCR extenders, baby monitors etc., are not going to be visible.

Clearly the software changed something. Practically, I think it's Apple trying to provide better performance for AirPlay and other network services. This means that it might not tolerate as many dropped packets as might actually be happening.

If you use file sharing in your house, what kind of "bandwidth" do you see when copying large files across the network. If you can use FTP, or other lighterweight, more likely to stream applications, that will provide more information. Also try speedtest.net to see if you see any visible differences in a wired vs wireless situation. That might make wireless radio issues more visible, but most of the time wireless speed, even with errors flying continuously, can out pace most peoples ISP bandwidth, so local file copies between machines inside of your network are more revealing.

If you have the experience, you can use "tcpdump" on your mac with the wireless up, and see if there are odd packets flying across the network indicating retransmission is occuring, or timeouts are causing resent packets.

I would like to chim in my own experiences.

Note: has been flawless for past 6 months.

Mountain lion , recent upgrade to firmware wifi dropping out every 10minutes. Not gray bars, just connection drop. mac book pro on same network working fine. 5Mhz.

Attempted to change MTU size based on this article http://j.mp/SdXLmu at macrumours. I used 1453 to play it safe.

No difference.

I have an airport. upgraded that to 7.6.1. no change.

now using the non 5 Mhz , been fine for last 24 hours.

DEFINITELY something in the firmware for the 5Mhz area of things.

Ben Forrest

Geodica Touchpass, User Strong Authentication Made Simple

see more at www.geodica.com

This issue was persistent in early Lion releases, but had been fixed at later upgrades. Upgrade your machine to 10.7.5, this issue is fixed now.

benforrestcc wrote:

I would like to chim in my own experiences.

Note: has been flawless for past 6 months.

Mountain lion , recent upgrade to firmware wifi dropping out every 10minutes. Not gray bars, just connection drop. mac book pro on same network working fine. 5Mhz.

Attempted to change MTU size based on this article http://j.mp/SdXLmu at macrumours. I used 1453 to play it safe.

No difference.

I have an airport. upgraded that to 7.6.1. no change.

now using the non 5 Mhz , been fine for last 24 hours.

DEFINITELY something in the firmware for the 5Mhz area of things.

I am not sure you can reach this conclusion with that logic. If the bars were always black, then your WIFI was working "as the pipe" to your router, but something between your computer and the "internet" was not working correctly.

Were you able to do any of the "ping" testing to see if you could get "ping -n 8.8.8.8" to work when your browser wasn't letting you access the website you were going to?

There seem to be many people like you who have had working "WiFi", but the browser was just not able to connect for some reason. That's the problem that still seems to be happening. With some people having ISPs with broken DNS or other services, it can be difficult to work through all the issues unless you've got a firm grasp of which parts of the internet infrastructure are used in what ways and at what moments, so that you can test what is working right up to finding what is broken.