That is correct. The 11th generation of servers and earlier were removed from the ISO to save space needed for adding the newer 14th and 15th generation servers.    That is also correct, it is any other updates needed beyond the listed, to include OS and apps.    Let me know if this helps answer your questions.    
Hi folks, I do have a few questions and I´d appreciate your support. I am running three Dell PowerEdge servers. My goal is to upgrade operating systems to newer versions as described:  Besides that, I want to upgrade firmware; iDRAC, BIOS, RAID, Dell Lifecycle Controller, etc. What would be the proper order?  What would be the right procedure, do I need to boot it via USB, or I can load files via iDRAC? I already did it for other server models, and it worked through the management UI where I loaded and installed all files.  Do I need to upgrade the firmware before or after XenServer and VMware upgrade?   Thank you in advance. Best regards Yaz
Upgrade Firmware and OS on Dell PowerEdge Servers