I have two x520 Dual NICs installed on a server running ESXi 6.7 U3 (Build:17700523). Each NIC utilizes Intel SFPs (E10GSFPSR) thus connect to the network via four fiber cables to a Cisco 9500 switch. The x520 NIC has been observed to randomly lose connection. I have attempted the following but the issue still persists:
- replaced the fiber cables, NIC SFPs, and Cisco switch port SFPs.
- verified cisco switch port is properly configured
- upgraded the Intel x520 driver to the latest v1.9.11
- installed the x520 on different PCI-e slots on the motherboard
- installed new x520 NICs
The Only way to regain connectivity is by resetting the NIC port from the ESX CLI. Does anyone have an idea what might be causing this random connectivity loss?
