Here is the excerpt from the User’s Guide on how to configure the BIOS , for more information here is the link for the User’s Guide and for more information on iDRAC ,click here
First, configure the BIOS to enable serial console:
1 Turn on or restart your system.
2 Press <F2> immediately after you see the following message:
<F2> = System Setup
3 Scroll down and select Serial Communication by pressing <Enter>.
4 Set the Serial Communication screen options as follows:
serial communication....On with serial redirection
via com2
NOTE: You can set serial communication to On with serial redirection via com1
as long as the serial port address field, serial device2, is set to com1, also.
serial port address....Serial device1 = com1,
serial device2 = com2
external serial connector....Serial device 1
failsafe baud rate....115200
remote terminal type....vt100/vt220
redirection after boot....Enabled
Then, select Save Changes.
5 Press <Esc> to exit the System Setup program and complete the System
Setup program configuration.