12-16-2015 05:15 PM - edited 08-02-2017 11:26 AM
We have one USG (firmware version 188.8.131.5296630) and three UAP-AC-PRO (firmware version:184.108.40.20664) in a rectangular office space of 4,000 sqft. The 3 APs are mounted under the ceiling. The closest distance between the APs is about 20~25 feet (see attached floorplan). We have under 40 wifi clients connected at the peak time, about 20 of them are MacBooks, the rest are mobile/tablet devices. At any moment, there are no more than 17 devices per AP. The network controller (v4.7.5) is running on Debian 8.2 hosted by Rackspace. Both 2.4 Ghz and 5 Ghz broadcast the same SSID.
Since we deployed the UAPs, users have been experiencing intermittent connectivity loss from time to time. When this occurs, the user's computer is showing nothing abnormal. The wifi connection is showing still connected, and the RSSI is also showing a decent number (between -50 dBm and -70 dBm). However, there is no connectivity until the user turns off and turns on the wifi, bascially by reconnecting to the wifi network.
We have tried adjusting the Tx power levels and channels on 2.4G and 5G, as well as setting RSSI threshold on APs to facilitate roaming. Most of our devices seemed to be able to roam successfully among APs when users moved from a locatioin to another (e.g. from their desk to a boardroom). We have also tried to reboot APs; but all these measures did not help to resolve the intermittent connectivity loss issue.