Been getting this error when deploying my application to Google App Engine.
When/If you encounter this, use the command
fuser -k 8080/tcp
You may have to try running it with sudo i.e
sudo fuser -k 8080/tcp.
On your console/command line. This will kill the process that was keeping port 8080 busy and everything should run fine.
Tried changing Google App Engine’s default bind address and port but that was proving too problematic.
I am running kubuntu(Ubuntu KDE Flavour) with default settings and configs.