Net/router guru advice needed (5Ghz network)

[Susurs]

I purchased Netgear WNDR4500 router and wanted to set it up the way that my MacBook Air (2010/Snow Leopard with latest updates) connects to it via 5Ghz network only.
The problem is that when I start up my Air one of the three times a message pops up on my MacBook saying "None of your prefered networks are available"
but below the message it offers to connect to the other found networks and my 5Ghz connection is listed there. If I press it connection starts immediately. Sometimes it connects without a problem.
If I add 2.4Ghz to known networks and MacBook can't connect to the 5Ghz (It's first prefered network in list) it connects to 2.4Ghz. There are no such problems with the other band.
However I'd like have automatic connection to 5Ghz allways not manual.
I tried different settings in router (security modes, no security, speed settings, network card access list, channels etc) but no luck...SSID's are CCC and CCC 5Ghz respectiveley.
Maybe there are some advanced settings in router to solve this or terminal commands in MacBook.

 

[thiggins]

The problem could be due to low/marginal signal level.

 

[Susurs]

Signal shows up as wery good and laptop is only 5ft away from the routter in the same room.

 

[thiggins]

Sorry, but I don't have any other ideas. Sounds like a bug related to the Air coming out of sleep/standby.

 

[rhombus]

Wild stab alert:

I've seen this in quite a few setups with Windows 7 coming out of standby. Exactly the same thing. Changing power save mode in the wireless card settings either to off or on (yes, it varies) has fixed it everytime. So maybe you could try that here if there is such an option? (Despite the usual advice for Windows being that disabling power save mode helps problems, I have actually found the opposite in Windows 7, and in fact disabling it has often caused this exact issue).

 

[sfx2000]

Sorry, but I don't have any other ideas. Sounds like a bug related to the Air coming out of sleep/standby.

I've had similar issues with my Macbook Air on Lion - only happens on some networks though, at home it's fine.

Some tips here...

http://reviews.cnet.com/8301-13727_7-20095988-263/fix-wi-fi-autoconnect-problems-in-lion/

I agree with Tim, recent Snow Leopard and Lion builds have been a bit buggy with WiFi

 

[Susurs]

So I think I solved it (at least somehow)...

I played with advanced airport preferences and set JoinModeFallback to KeepLooking instead of default DoNothing


Command line:
sudo /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport prefs joinmodefallback=keeplooking

Now if at startup Air can't connect to my 5Ghz with first time it attempts a reconnect after some seconds and succeeds.

Now only problem is that I need to find how to set interval between those reconnect attempts (if there is a way to control it) to like 5secs cause it's too long. (Reconnect always happens after like 20sec if not connected with first attempt).

Any ideas?

From the other side...if Air will be switched on where there are no networks and I decrease this interval - the battery life will suffer...

 

[Susurs]

By the way...Is it possible to create a script like this: If SSID "CCC" detected initiate a reconnect in 30 seconds ... ? or something like that ...