DELL iDRAC not showing second raid controller?

Question

network hardware

The DELL r240 server
in the BIOS shows two controllers

through iDRAC, only one

is visible. Why is the second not visible?
BIOS and iDRAC versions are latest.

Answer 1

Dell PERC S140 is a software controller. The software for it under Windows and Linux is at least different. As a maximum, there may not be full support for Linux, only Windows (it is better to check with the vendor).
In addition, in the Configuration wizard, at the RAID configuration step (where the Select controller is), there should be a RAID type item, and in it - Windows RAID and Linux RAID. There you need to select the desired option.