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xarissm
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CentOS 6.3 KVM under ESXi5.1

hi all,

here is my case,

i want setup CloudStack in a box and i will use ESXi 5.1 for this,

My CPU on psysical H/W support IntelVT bu no PET

according with the link bellow 

Running Nested VMs

http://communities.vmware.com/docs/DOC-8970

in the section  Running Guest Hypervisors without Virtualized HV state this is possible to run Centos x64 KVM, but when tested Centos vm dont recnogize VT technology  on vm's CPU info so can't install kvm modules on kernel

but in the main article Running Nested VMs under section Special Considerations states that can be done only with ESXi 5.0 and not ESXi 5.1?

any second thoughts οr i am missing something here?

KVM section of the article state that "KVM requires hardware-assisted virtualization, so it can only be run under ESXi 5.0, Workstation 8, Player 4 or Fusion 4 (or later)" so this scenario will run only at ESXi 5.0 and not at ESXi5.1?

(relative config like monitor.virtual_exec = hardware monitor.virtual_mmu = software has been tested with no results)

thank you for time

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Correct.  It is possible to use virtualized HV under ESXi 5.0 on systems without EPT/RVI, but not recommended, due to the abysmally poor performance.  When we officially introduced the feature in ESXi 5.1, we decided not to support hosts without EPT/RVI, because the feature was not product quality.

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admin
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Correct.  It is possible to use virtualized HV under ESXi 5.0 on systems without EPT/RVI, but not recommended, due to the abysmally poor performance.  When we officially introduced the feature in ESXi 5.1, we decided not to support hosts without EPT/RVI, because the feature was not product quality.

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xarissm
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thank you for cross check this Smiley Happy

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xarissm
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another question please

try to run the Centosx64 on my home lab

Win7x64

Intel Quad Q9400

vmWorkastion 8

(i have already run vsphere 4 here with no problems)

according with the Netsted VM Guide (links above)

in the config file of the Centos i added the following

monitor.virtual_exec = "hardware"
monitor.virtual_mmu = "software"
vcpu.hotadd = "FALSE"

(vmware workstation server service restarted)

but i cannot load in to the Centos the command "modprobe kvm-intel" it return "Operation not supported"

and also when i run the "egrep '(vmx|svm)' --color=always /proc/cpuinfo" to check CPU support for VT nothing returns

what is the problem here...what is missing?

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admin
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The Q9400 does not support EPT.  For Workstation 8, EPT/RVI is required for virtual HV support.

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xarissm
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true Q9400 dont support EPT but i am confused now, so why i am able run vsphere 4 (esx/esxi4) on the Q9400 with vmworkstation 8?

i just want to run CentOS KVM x64  and just create x86_32 virtual machines, like i do on vsphere4 for learning

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admin
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xarissm wrote:

true Q9400 dont support EPT but i am confused now, so why i am able run vsphere 4 (esx/esxi4) on the Q9400 with vmworkstation 8?

vSphere 4 does not require VT-x to run 32-bit guests, so you don't need virtualized HV.  If you wanted to run 64-bit nested guests under your vSphere 4 VM, then you would need EPT on the physical host.

i just want to run CentOS KVM x64  and just create x86_32 virtual machines, like i do on vsphere4 for learning

KVM is not capable of running 32-bit guests without VT-x.

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admin
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Jim Mattson wrote:

KVM is not capable of running 32-bit guests without VT-x.

Well, I take that back.  Maybe it is, through qemu emulation, but you won't be able to load the kvm-intel kernel module without VT-x.

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xarissm
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so i will have to setup the Centos KVM on Xeon 5405 (not support EPT) with ESXi 5.0 right?

the config must be

1)on ESXi5.0 the

vhv.allow = "TRUE"

2)on config file of the CentOS (vm on ESXi5.0 guest hypervisor)

vcpu.hotadd = "FALSE"
monitor.virtual_exec = "hardware"    because Xeon 5405 support Intel VT
monitor.virtual_mmu = "software"     because not support EPT

is this setup ok?

PS: thank you for fast reply btw

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admin
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If you install ESXi 5.0 on the bare hardware (not in a VM), this will work, but performance will be terrible.  Your CentOS VM will also need the following option:

cpuid.1.ecx="----:----:----:----:----:----:--h-:----"
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xarissm
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thanks

i will try this and i will update

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xarissm
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unfortunately doesnt work

on ESXi 5.0 with  Xeon 5405

vhv.allow = TRUE and reboot ESXi

on VM Centos H.V 8 OS type CentOS 4/5/6 x64

monitor.virtual_mmu = "sotware"
monitor.virtual_exec = "hardware"
vcpu.hotadd = "FALSE"

or

monitor.virtual_mmu = "software"
monitor.virtual_exec = "hardware"
vcpu.hotadd = "FALSE"
cpuid.1.ecx="----:----:----:----:----:----:--h-:----"
when i run the command
egrep '(vmx|svm)' --color=always /proc/cpuinfo
no info returned to indicate that Virtualization is supported on VM
what i am missing here?
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xarissm
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sorry my mistake

i had vhv.enable = TRUE instead of  vhv.allow = TRUE (this is the correct) on ESXi

thanks again for the help the command "egrep" now returns virtualization support under Centos x64 "guest hypervisor"

correct config on Centos VM will be

cpuid.1.ecx="----:----:----:----:----:----:--h-:----"
monitor.virtual_exec = "hardware"
monitor.virtual_mmu = "software"
vcpu.hotadd = "FALSE"

Regards

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