NIC Showing “Network Cable Unplugged” on Intel NIC

 

Last week we’ve encountered a symptom “Network Cable Unplugged” on the Intel NIC which resides in DELL R720. Our scenario consists of 4 Broadcom NIC and 4 Intel NIC (Label as LAN5, 6, 7 and 8). Then we realized that sometimes the NIC on either LAN 5, 6 or 7 will shown unplugged. We initially thought that it is because cable loose. However , it is not the CAT6 issue. Our temporary solution is “Disable” and “Enable” the NIC and the connection will back to normal. However this is just a temporary solution as the symptom is back.

Next action is

1. Update the NIC with latest driver

2. Disable TCP Offload

However it is not solved. Next this is our solution

Resolution

Disable Energy Efficient Ethernet

1. On the Intel NIC, go to Advanced | On Energy Efficient Ethernet | Set the value to Off.

Now after a week of monitoring, our issue of “Network Cable Unplugged” on the Intel NICs are solved and no more interruption to the Hyper-V Server.