networking - After network restart, device not ready Xubuntu 16.04, Intel 3945ABG Wireless card - Ask Ubuntu

when wifi drops, disable , re-enable wifi. sometimes, doesn't fix problem. show no networks. reset network sudo service network-manager restart , device not ready

i end having reboot , fixes things temporarily, until next time. how fix don't have restart computer every , again?

as suggested @vbf below, ran these commands , got these results when things stopped working.

here output of ifconfig:

enp9s0    link encap:ethernet  hwaddr 00:18:8b:dd:24:32             broadcast multicast  mtu:1500  metric:1           rx packets:0 errors:0 dropped:0 overruns:0 frame:0           tx packets:0 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            rx bytes:0 (0.0 b)  tx bytes:0 (0.0 b)           interrupt:18   lo        link encap:local loopback             inet addr:127.0.0.1  mask:255.0.0.0           inet6 addr: ::1/128 scope:host           loopback running  mtu:65536  metric:1           rx packets:10682 errors:0 dropped:0 overruns:0 frame:0           tx packets:10682 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1            rx bytes:724653 (724.6 kb)  tx bytes:724653 (724.6 kb) 

the output of nmcli co:

name                       uuid                                  type             device  netgear63                  7796f00a-6ffa-4154-aff1-62af90c3d8e8  802-11-wireless  --      netgear63 1                979c058f-cb41-4910-bbab-37b86d76bb5e  802-11-wireless  --      samsung galaxy avant 4539  b8601380-8e76-4c9c-be74-cfa7f33865be  802-11-wireless  --      wired connection 1         93b93cbb-b063-30aa-8ea4-7cc61db203f6  802-3-ethernet   --      

the output of command nmcli networking connectivity check was

none 

and , lastly tried both nmcli con id "netgear63 1" , nmcli con id "netgear63" , got output:

error: connection activation failed: no suitable device found connection. 

update: laptop uses intel 3945abg wireless card.

from looking around on internet, problem may related power management wifi card related these pages: http://www.intel.com/content/www/us/en/support/network-and-i-o/wireless-networking/000005875.html , wireless connection keeps dropping intel 3945abg card

to solve problem, power management card may have disabled. above forum pages solutions doesn't work version of ubuntu have (16.04).

to turn of power management of wifi, following:

run iwconfig. see chip-set whether power management on or off. open /etc/networkmanager/conf.d/default-wifi-powersave-on.conf, should see

[connection] wifi.powersave = 3 

change 3 2, save , reboot.

run iwconfig , should see power management:off

source: https://sites.google.com/site/easylinuxtipsproject/internet