Wifi dropping and SSID's not visible

[JeffV]

Greetings

i know this is less of jamf/casper issue, however we'd ran into a wall with this one.

For a while now we have an issue in a couple of our offices with the combination of wifi and mac's.
The symptoms: wifi connection drops, when trying to reconnect the ssid's are not visible. when inserting a usb-wifi dongle. that can connect fine to the same SSID's. when walking over to a other part of the building the ssids become visable again, and walking back the issue is (temporary) resolved.

The symptoms are occurring on all kinds of mac's (air 2008 and above till current) ProRetina's till current, osx 10.8, 10.9 and 10.10. both casper imaged, and retail. ios devices running 6,7,and8)

the environment: over 150+ap's multiple sites, in a WLC environment. ssid's with both 802 authentication and with wpa and without auth. all effected.

Troubleshooting performed: - connected a mac to a usb wifi dongle: no further issues
- bluetooth disabled, no effect, ssid's still inviable
- tested with windows machine's : not affected by the symptoms. - fast ssid changing on the wlc is enabled

if anyone has some insights / thoughts / fixes, or experiences the same, some tips would be appreciated. thanks jeff

[merps]

@jeff.vrieling We came across this issue on 10.10.1 & 10.10.2, but it has been fixed with 10.10.3.

For us, the issue was caused by disabling DNS multicast. We weren't applying this security configuration item on Mountain Lion, so I can't speak to that.

Since mDNSResponder has been replaced by discoveryd in Yosemite, here's the line of code that has been ruining Wi-Fi (only tested built-in adapter) before 10.10.3.

#!/bin/sh
/usr/libexec/PlistBuddy -c "Add :ProgramArguments: string --no-multicast" /System/Library/LaunchDaemons/com.apple.discoveryd.plist

I'm not sure what your security configuration looks like, but this might help point you in the right direction.

[JeffV · Accepted solution]

For all those interested, an update on this side,

the problem has been resolved by upgrading the F.U.S. (Field Upgradable Software) to the latest version on the cisco wireless lan Controllers.

apparently the issue was in a certain combination between a certain FUS version and code version.
hope this helps other fokes who might run into an similar issue.

[sggr57a]

Which version of FUS did you upgrade to?

[JeffV]

we upgraded from 1.5 to 1.9 (not in 1 go) hope it hepls.

also i found this quite helpful"
http://thewifiguy.net/2014/06/15/whats-all-the-fus-about/
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