Half the time, after my laptop resume from sleep, the Network Manager remains in the sleep state.
There are multiple reports about this problem. It occurs in Ubuntu 14.04, 14.10 and 15.04.
Obviously, for any normal consumer, the only solution would be to reboot the computer, half the time. Not acceptable.
For the Linux literate, a CLI based workaround can be found here. Essentially, one can run:
sudo nmcli nm sleep false
Following, the multiple reports of the same problem:
- 10ec:818b [Lenovo ThinkPad T440] WiFi does not reconnect after resuming from sleep in Ubuntu 14.10 - Launchpad bug #1386863
- Wifi doesn't reconnect after waking from sleep - Launchpad bug #1390709
Before I found the above solution on the net, my solution was to restart the Network Manager with:
sudo restart network-manager
This caused nmapplet to crash without reason. I opened the following bug report regarding this issue.: