MX7000 update

Hi all

we have an MX7000 with running firmware 1.20.10 and we want to update it to the last one 2.20.10

the MX7000 is not connected to internet. 

we will use the Dell Update Package method (DUP) 

1. should we only download the OME firmware package and start update or we need also to download other packages such as idrac , ... 

2. can we move directly from 1.20.10 to 2.20.10 ? 

Thanks