I’m running a fresh install Ubuntu Gnome 16.10 on my XPS 15 and I noticed that whenever I put the laptop in suspend I was unable to connect to my WiFi network upon resume.

Looking online it appears that I am not alone with this problem. Following the discussion found that restarting the network-manager service fixed this.

sudo systemctl restart network-manager.service

You can automate this by creating a new systemd service which calls this whenever coming out of suspend, hibernate, or hybrid sleep.

First create the new service by sudo nano /etc/systemd/system/wifi-resume.service and pasting the following content:

[Unit]
Description=Restart NetworkManager at resume
After=suspend.target
After=hibernate.target
After=hybrid-sleep.target

[Service]
ExecStart=/bin/systemctl --no-block restart network-manager.service

[Install]
WantedBy=suspend.target
WantedBy=hibernate.target
WantedBy=hybrid-sleep.target

Credit go to the authors of the replies on ask ubuntu thread.

Save and exit nano and then enable the new systemd service:

sudo systemctl enable wifi-resume.service

You can substitute enable with disable to turn off the service and then remove the file if you find it’s not working as expected.

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