[Solved] Dual CPU Issue

[Jazzy348]

Hi,

I fresh installed CentOS 7 on a Dell Poweredge R410 with two Intel Xeon x5670. If I assign more than 6 cores to a guest, the guest does not boot. The guest either boot loops or errors. What can I do?

Kind regards,
Jazzy.

[socratis]

We're going to need a complete VBox.log, from a complete VM run:

• Gathering the necessary information:
  1. Start the VM from cold-boot (not from a paused or saved state).
  2. Observe the error. RECORD THE ERROR EXACTLY!
  3. Shutdown the VM (force close it if you have to).
• With the VM completely shut down (not paused or saved), right-click on the VM in the VirtualBox Manager and select "Show Log".
• Save only the first "VBox.log", ZIP it and attach it to your response. See the "Upload attachment" tab below the reply form.

[Jazzy348]

Hi,

Please find attached ZIP with the VBox.log and screenshot of the error.

Thanks,
Jazzy.

[socratis]

VirtualBox VM 5.2.12 r122591 linux.amd64 (May  9 2018 15:06:43) release log
00:00:00.029974   Oracle VM VirtualBox Extension Pack (Version: 5.2.0_RC1 r118201; VRDE Module: VBoxVRDP)

The Extension Pack (ExtPack) gets installed on the host and it has to match the VirtualBox version. You haven't updated your ExtPack for ages...

Is that why you completely disabled the USB controller?

00:00:00.083604 NumCPUs <integer> = 0x0000000000000018 (24)
00:00:00.233279 CPUM: Physical host cores: 12
00:00:00.233612 Full Name: "Intel(R) Xeon(R) CPU X5670 @ 2.93GHz"

You have assigned double the CPUs to the VM than you actually have. The host is going to run low on resources, since VirtualBox cares about physical processors, not logical ones. See "CPU Cores versus threads" and "Why is it a bad idea to allocate as many VCPUs as there are physical CPUs?". Your Xeon X5670 has 6 cores, not 12.

00:00:00.083917 [/Devices/ichac97/0/Config/] (level 4)

Any particular reason why you didn't go with the default HDA and you chose to go with the ICHAC97?

00:00:09.824757 APIC0: Attempt to read reserved/unknown MSR (0x80e) -> #GP(0)
00:00:09.824775 IEM: rdmsr(0x80e) -> #GP(0)
00:00:09.824831 GIM: HyperV: Guest indicates a fatal condition! P0=0x1e P1=0xc0000096 P2=0x6fe36431 P3=0x0 P4=0x0

And this is I believe where the error happens. Can you change the VM Settings » System » Acceleration » Paravirtualization Interface to "None" and see if that changes the situation as well? I don't think it will, since I think that this is just reporting back...

[Jazzy348]

Hi,

Updating the EXT pack seems to have helped, thanks!. To answer your questions...

USB are disabled by default, I run the server remotely and have no need for USBs.

The default HDA for me is ICHAC97... I'm using PHPVirtualBox so that may be why.

Switching to "none" for the Paravirtualization I believe also resolves the problem, so again thanks for that!

[socratis]

• In the future try to avoid troubleshooting an RDP client. It adds more parameters to the problem.
• The default for the sound card of a Win2012 template is the Intel HDA, don't know why you have ICH97.
• I believe that it was the ExtPack and not the paravirtualization option, but... hey, it works!

Marking as [Solved].