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I'm trying to run my VMware ESXi within a VMware virtual machine. It fails to boot with the following message -

Could not load multiboot modules: Admission check failed for memory resource
  • What does error mean?
  • Is it possible to boot ESXi within a VM?
  • Am not setting up the VM correctly?
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You need more memory for your virtual machine guest os, ESXi requires at least 2GB memory.

See Requirements:

    Minimum: Single socket, dual core
    Ideal: Dual-socket, 4 or more cores per CPU

    Minimum: 2GB
    Ideal: 8+GB

    Minimum: one NIC, plus one for Management interface
    Ideal: One for Management Interface plus multiple NICs for VMs

Local Storage (SATA/SAS)
    Minimum: one 80GB drive
    Ideal:2 mirrored drives, plus 4 RAID5 drives for VMs

Shared Storage
    NFS, iSCSI, Fibre Channel for VM storage
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Yes, it definitely can.

I do it all the time for training purposes.

The processor needs to have at least VT-X and VT-D. A I7-3770 is great - but the I7-3770K may run into issues.

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ESXi runs only on bare metal. It is not possible to boot it in a VM.

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How does it know it's running within a VM? And references please.. – Kshitiz Sharma Jan 16 '13 at 14:05
i think ESXi can run inside a virtual machine, i've already installed ESXi using VMware Player (assigned 2GB memory to it) – LiuYan 刘研 Jan 16 '13 at 14:08
Weird. They do advertise their product as the Bare-Metal Hypervisor on the page I linked to. – Hennes Jan 16 '13 at 14:17
@Kshitiz Sharma For a lot of details, see http:// (best explanation I found, but way too much content to copy. Even when ignoring copyright issues). – Hennes Jan 16 '13 at 14:17
@Hennes Not weird at all. Theoretically an application running in a virtualized environment shouldn't be able to tell if it's on a real machine or not, otherwise the emulation isn't correct. Bare metal hypervisor merely means that it runs without another OS, not that it'll literally only run on actual metal. – Kshitiz Sharma Jan 16 '13 at 14:26

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