Mirror download, domain analysis, time synchronization, please click Ali Cloud Open Source Mirror Station
E: failed to fetch problem occurs using sudo apt get-install.
Replace the mirror source
Error Cause: In most cases, the Download source of ROS updates is normal, so this problem should be some configuration settings of your own system.
Since the network has problems, we replace the downloaded source:
Use Gedit or VI / VIM to open the configuration file:
Sudo gedit /etc/apt/sources.list
Sudo vim /etc/apt/sources.list
Replace all content
Then take effect configuration file (refresh list)
Note: Be sure to perform refresh
Configure DNS gateway
Enter a command under Terminal
Sudogedit / etc / resolv.conf
Sudovi / etc / resolv.conf
Add Ali DNS in Resolv.conf