iDRAC not accessible with Dell EMC XC Core XC740xd

Hello,

with one of our Dell EMC XC Core XC740xd server, the iDRAC is not accessible anymore.

Before, we could not change the idrac IP address, we always get an error. After upgrading BIOS with BIOS_72VRD_WN64_2.21.2.EXE and iDRAC with iDRAC-with-Lifecycle-Controller_Firmware_3NNH8_WN64_7.00.00.172_A00.EXE, we are able to change the IP address and idrac password.

but for unknown reason, the IP address and password always reset to the previous setting (old IP address and password).

This server restart automatically sometimes, and we decide to reset iDRAC. When the iDRAC is accessible, there is no hardware issue from the TSR file.

Trying to reset the iDRAC from web interface failed. 

Restarting the server and enter to lifecycle, executing the hardware diagnostic, we have aborted this process because it takes around 34hours by hitting ESC keyboard as suggest in the screen.

after aborting this process, idrac is not accessible anymore, and lifecycle controller is disabled.

sorry for the long explanation.

attached the error we get.

we have unplugged the power cable, wait 30s and power on the server, the issue still occurs.

Thanks in advance for your answer.

Regards,