I'm reimaging an NBU 5230 appliance and have the 126.96.36.199 ISO on a USB drive. I have put the USB into the back of the appliance but when the boot menu comes up (after an F6), it doesnt list a CDROM but just the USB drive, amongst the RAID controller and the EFI option. I try to boot the USB anyway but it then tells me its an unrecognised filesystem and dumps me into the grub rescue prompt.
I download the ISO direct from fileconnect and when I check the ISO on a MAC or PC it looks fine.
Any ideas? Do I need to do something else to the ISO or anything in the boot menu of the appliance?
Just putting an ISO on a USB drive doesn't make it bootable and recognizable as an ISO bootable device. You need a device that looks like a virtual CDROM.
There are utilities on the net that can make a USB key look like a CDROM device and load an ISO, or you can burn the ISO to a disc and use a USB DVD drive, or you can as Riaan suggests, use the IPMI redirection funciton to mount the ISO over IPMI. There are also hard drive cases that have a CDROM virtualization capability that allow you to put ISO files on them and boot from them.
To boot directly from a USB key without the CDROM emulation, you need the keys that came with the appliance, which are built with IMG files and made bootable.