16.04 LTS wifi connection issues with Realtek RTL8723BE adapter

Finally I was able to fix the issues after trying out numbers of different methods.

1. Get details of your PCI wireless card by running sudo lshw -class network

2. Get your card model info according to the product line.
   For instance, as you can see in the question description it says
   product: RTL8723BE PCIe Wireless Network Adapter so the model of my card is RTL8723BE

   Or product: RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller so the model of my card is RTL8101/2/6E

3. Give the permission sudo chmod 755 /etc/pm/config.d/

4. Open or create config and add SUSPEND_MODULES="rtl8723be"(replace rtl8723be with your own model number)
   Then run
   echo "options rtl8723be fwlps=N" | sudo tee /etc/modprobe.d/rtl8723be.conf
   (note that when replacing rtl8723be with my card which is RTL8101/2/6E i should only type .../modprobe.d/RTL8101.conf; and /2/6E shouldn't be written)

Finaly restart your system.

Now your system should be able to reconnect automatically after sleep, and wifi connection never got lost once for me after doing this.

"The up/down arrows is likely a network manager bug that results in network manager thinking the wifi device is actually ethernet.", according to Jeremy31.see bug info here You should be able to fix it by installing NetworkManager-1.2.0.

Thanks to Jeremy31 for providing the solutions.

I have the exact same problem. After waking from sleep, wifi still works but networks not showing. I solve the problem by restarting the network manager.

sudo service network-manager restart

Still very annoying. I hope they fix this issue soon.

This is a bug for sure. Bug has been filed at https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1574347