Yun did not connect to WiFi after configuration and restart When examined we find that Yun is still in master mode and 0% signal.

Any procedure known to solve this problem manually?

We can access Linux command under Mater mode AP-mode and print WiFi status

/usr/bin/pretty-wifi-info.lua


We know procedure to change REST API access

Method II:  config file

opkg update
opkg install nano
nano /etc/config/arduino

config arduino
        option password '775e9f944188a7bcb36e9ca5dc51672b44bcceeb7d56d89dfb914e$
        option wifi_reset_step 'clear'
        option secure_rest_api 'true'
...

Merhod 1:  UCI API    need access to the Linux system by YSM program


PASSWORD

uci set arduino.@arduino[0].secure_rest_api=true


OPEN:

uci commit arduino


Is there any procedure manually to perform the configuration by hand for the mode:


change to client?
then restart?
from master mode where we have access to Linux command line?


This question has been left unanswered before in all forums examined.
Maybe someone knows the answer.

The problem lies in the Linux not in the hardware or routers or PC, as proven by testing.
My wireless config is in the /etc/config/wireless, not in the /etc/config/arduino

How do you configure your Wifi ?
There is at least 4 methods  :
you can do this through OSJS, through LUCI, through ARDUINO IDE, or with UCI.