description of the problem
It seems both wifi and ethernet has the same problem. However, it seems it only happens when the suspend time is long. If I close lid for about 5 min or so, it is OK. However when I suspend for hours, when coming back, I can't connect to the internet. I have tried:
sudo systemctl restart network-manager.service sudo service network-manager restart sudo service NetworkManager restart
None of them helps, even log out. The only way to resume the network is by a restart.
I found some post on the web such as this one: Wifi doesn't work after suspend after 16.04 upgrade, but it doesn't help even there are so many vote ups, therefore I think it is OK to ask this question again to draw some attention and hopefully my problem can be solved.
-> ~$ lspci -knn | grep Net -A2 03:00.0 Network controller : Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter [10ec:8176] (rev 01) Subsystem: Realtek Semiconductor Co., Ltd. RTL8188CE 802.11b/g/n WiFi Adapter [10ec:8195] Kernel driver in use: rtl8192ce