The default user and password combination for a Dell iDRAC interface is root / calvin
It can be manually reset when logging in to the web interface but when doing many machines at once and many actions at the same time the racadm tool is handy. To change the password use:
racadm -r 192.168.1.23 -u root -p calvin set iDRAC.Users.2.Password "ChAnGeMe"
Note that the ‘root’ admin user has the ID of 2. I think that is for historical reasons going back to DRAC4. Also note that the syntax has changed. The older method was to use :
racadm -r 192.168.1.23 -u root -p calvin config -g cfgUserAdmin -o cfgUserAdminPassword -i 2 newpassword