iDRAC on DELL Server

BMC and iDRAC

1. How is iDRAC different from BMC? Is it just a different name?

--On servers from 11th gen and older the BMC was the embedded mgmt controller, where the iDrac was an add on card. The BMC does have some of the remote access logic, but the GUI and other features were from the iDrac. 

2. How can I access BMC without installing iDRAC software?

--As there is no GUI for BMC, it would be done by CLI using IPMI.
3. Can I access BMC from linux?

--Yes and the BMC will allow you to power off and on systems, and serial over LAN access, which is why you mainly see BMC discussions around Linux. 
4. From where can I download the BMC firmware?

--If you go to support.dell.com and enter the system model, then select Driver and Downloads, under Embedded Server Mgmt you will find the BMC Firmware, as well as the iDracs. This will only be on 11th generation and older, as the 12th generation and on embedded the iDrac.