We have an R710 server that also has the same iDRAC6 not responding and also reports the Inventory failure message (whilst attempting to update from Linux Centos6.4).
Was there ever a way past this failure?
Looks like problem that cannot update the lifecycle controller because cannot find the lifecycle controller, but surely it is built into the motherboard?
BIOS version is 6.3.0 but also had this same problem with BIOS 1.0.4.