ovs-vsctl: Error detected while setting up 'eth0': could not open network device eth0 (No such device).

This error message suggests that the network device "eth0" is not present on the system. This could be due to a number of reasons, such as the device being disabled, not properly installed, or being renamed.

To resolve the issue, you can try the following steps:

1. Check if the device is present by running the command `ifconfig -a`. If the device is not listed, it may not be installed or recognized by the system.

2. Check if the device is enabled by running the command `sudo ifconfig eth0 up`. If it is disabled, this command will enable it.

3. Check if the device has been renamed by running the command `ip link show`. This will show a list of all network interfaces and their current status. If the device has been renamed, you will need to update the configuration files accordingly.

4. If none of the above steps work, try restarting the network service by running the command `sudo systemctl restart networking.service`. This will restart the network service and may help resolve any issues.

If the issue persists, you may need to consult with a network administrator or seek further assistance from a technical support team.