Clients take long to connect to SSID, high packet loss

[Jannik]

Hi,

my customer is running a FG-100F v7.2.9 with FAP-221C on the latest firmware. It wokred pefectly fine until from one day to another it didn't. Clients try to connect to  SSIDs, it takes very long and often fails. When it works the conenction is very slow with high packet loss (~85%). I checked the logs and saw high numbers of log entires for "wireless ip assigned" and "wireless client authenticated". I checked the details of these entries and saw the same mac-addresses doing this in short intervals as if they frequently re-connect. Has anyone else experienced this? What could be the issue? I checked config wireless-controller settings -> fapc-compability enable, config wireless-controller wtp-profile - 221c-profile -> dtls enable but nothing helped. I saw high CPU usage for cw_acd process and a matching BUG ID for resolved issues on fortiOS 7.2.9 so i upgraded from 7.2.8 to 7.2.9 and it made no difference. I have no ideas anymore.

[AEK]

Hi

It can be caused by channel interference.

Can you share a screenshot from menu WiFi & Switch Controller > Managed FortiAPs, then right click on the affected AP > Diagnostics and Tools