An operational error occurred either because there was no route to the network or because negative status information was returned by intermediate gateways or switching nodes.
The returned status is not always sufficient to distinguish between a network that is down and a host that is down. See the No route to host message.
Check the network routers and switches to see if they are disallowing these packet transfers. If they are allowing all packet transfers, check network cabling and connections.
The symbolic name for this error is ENETUNREACH, errno=128.