Raspberry Pi Wireless Device Power Off

I use my device as headless as a home server and as a jump box. From past quite some time I was noticing that my Raspberry Pi was not accessible over the network after some period of in-activity. And since it is headless, the only way to get the network back was either take out the USB Wireless adapter or Reboot the Pi (through the power switch). I chose to take out the adapter and reseat it. However, this was causing my RPi to reboot also, may be because in the process the power connector was getting disturbed. I will revisit this point later.

In order to switch off the power saving for my wireless device I tried

$ sudo iwconfig wlan0 power off
Error for wireless request "Set Power Management" (8B2C) :
    SET failed on device wlan0 ; Operation not permitted.

I am using NetGear USB wireless adapter and it load the kernel module 8192cu. Checking

$ cat /sys/module/8192cu/parameters/rtw_power_mgnt 

I realized that the power saving is still on (1 indicates minimum power saving). So I created a module config file as below to permanently set the power saving to 0 and rebooted the RPi.

$ sudo vi /etc/modprobe.d/8192cu.conf 
# Disable the power management during boot - Ajitabh
options 8192cu rtw_power_mgnt=0
$ sudo reboot

Checking again confirmed that the power management has been disabled.

$ cat /sys/module/8192cu/parameters/rtw_power_mgnt 
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