You can fix this by adding an entry to your
/etc/hosts for your machine's hostname.
If you want a one-liner, something like this will do it:
printf "\n127.0.0.1 $HOSTNAME\n" | sudo tee -a /etc/hosts
This will append a line to your
hosts file that will resolve the current hostname to
When you run the command above you'll be prompted for the root password you set when the Windows Linux subsystem was installed. Also, since this command starts a shell for the root user just before it runs you'll actually see the
sudo: unable to resolve host WHATEVER message one last time just before the change is made.
Alternatively, you run an editor (such as
nano) as root and add the entry manually:
sudo nano /etc/hosts