If you have problems connecting to older Dell idracs that require an outdated java, you can use this app. It's a simple batch file on top of a standalone java bin with the security settings preconfigured to work.
Just run the batch called idrac.bat and the script will ask for the server url (for the idrac and not the main server) and login details. Then it will launch the internal java and connect you to the console with the full ability to mount ISOs.
No need to authenticate on the idrac website for it to work beforehand. It's pretty quick too.