I have been experiencing issues with wireless network connectivity at one location recently while using my MacBook Pro laptop running OS X Yosemite (10.10.5). Until fairly recently, wireless network connectivity at the location was great, but recently I would find that SSH connections I made from the laptop to another MacBook Pro laptop were constantly being dropped requiring me to re-establish the connection. And when I would ping the other system, which I was accessing via the wireless network, I would see "request timeout" messages. I would also see "request timeout" messages when I pinged the router's address. A few minutes later I might be able to successfully ping both systems. Or I could go to System Preferences , then double-click on Network, and then click on "Turn Wi-Fi Off" and then, after WiFi connectivity was disabled, I could turn it back on and the Wi-Fi access would then work.
$ /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -I agrCtlRSSI: -56 agrExtRSSI: 0 agrCtlNoise: -87 agrExtNoise: 0 state: running op mode: station lastTxRate: 73 maxRate: 72 lastAssocStatus: 0 802.11 auth: open link auth: wpa2-psk BSSID: 94:44:52:4a:43:40 SSID: Rain MCS: 7 channel: 11
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