How to prevent wifi sleep after suspend for Ubuntu Linux

 1. Change power state of the wifi card to 3

```

$cat /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf

[connection]

wifi.powersave = 3

# Slow sleep fix: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1670041

#wifi.powersave = 2

```

2. After saving the file run `sudo systemctl restart NetworkManager`

3. Make a reset bash script and name it `iwlwifi-reset`

```

#!/bin/sh

# NAME: /lib/systemd/system-sleep/iwlwifi-reset

# DESC: Resets Intel WiFi which can be flakey after a long suspend.

# DATE: Apr 1, 2017. Modified August 30, 2017.

MYNAME=$0

restart_wifi() {

    /usr/bin/logger $MYNAME 'restart_wifi BEGIN'

    /sbin/modprobe -v -r iwldvm # This removes iwlwifi too

    /sbin/modprobe -v iwlwifi   # This starts iwldvm too

#    systemctl restart NetworkManager.service

    /usr/bin/logger 'systemctl restart NetworkManager.service (SUPPRESSED)'

    /usr/bin/logger $MYNAME 'restart_wifi END'

}

/usr/bin/logger $MYNAME 'case=[' ${1}' ]'

case "${1}/${2}" in

    hibernate|suspend|pre*)

      ;;

    resume|thaw|post*)

      restart_wifi;;

esac

```

4. Copy the iwlwifi-reset script to systemd folder

```

sudo cp -r /path-to-iwlwifi/script /lib/systemd/system-sleep/

```

5. Set excute permission for the script

```

chmod a+x /lib/systemd/system-sleep/iwlwifi-reset

```