How to set static IP for DE10-Standard LXDE image
From Terasic Wiki
1.Try to use the Vim command to create the /etc/network/interfaces file as below first:
2.Then set IP adress as you want. Here, we set IP address 192.168.21 .123 as an example:
3.After editing the file, using :wq to save the file, and "ifup eth0 " to active the setup.
Note: You can also use this methord to set the static IP for DE10-Nano LXDE image.