Network connectivity issues

Make sure that the network cables are connected correctly.

Check that the network cable is connecting the nodes to the network switch.

Try replacing the cable with a cable from a known working system to rule out a bad cable or switch connectivity issues.

Make sure the eth0 interface is connected to the network by issuing: ethtool eth0 The port that’s currently connected will have "link detected" in the last line of the output.

If the networking settings have been reconfigured, reboot each of the nodes.