BladeSystem Server Blades

ProLiant BL460c Gen10 loses network


ProLiant BL460c Gen10 loses network

Hi, we have lots of identical Blade ProLiant BL460C Gen10 with an identical setup

One of these servers loses the network every now and then. When checking with ILO the Status of all 4  Adapter Ports  (2 physical network adapters) is shown as "Unknown" and the server has no IPv4 adress, so it can´t respond. Only a reboot solves the problem.

HP replaced both HP FlexFabric 20Gb 2-port 630FLB Adapter and later the system board. (Latest FW)  Still same problem. We moved the server to another bay in the same enclosure, but also no effect.

Can´t find any hints in the logs. 

Any ideas?