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19

Like chanting Bloody Mary into a darkly-lit bathroom mirror, let's see if we can get Jake Oshins to show up... Gang scheduling is also referred to as co-scheduling. I think VMware prefers the term co-scheduling to gang scheduling. In ESX versions prior to version 3.x, VMware used "strict" co-scheduling, which had the synchronization drawbacks. In ESX 3.x ...


13

Type 2 hypervisors are rather useful, though not commonly in mainline production environments. A T2 hypervisor such as VMWare Workstation can have the ability to produce Virtual Machines that are instantly useable on the T1 version (ESXi) just by uploading the right files, which makes it very handy for VM prototyping. As a class though, T2 hypervisors are ...


13

In theory, no. The whole point of the hypervisor is to isolate virtual machines from each other. In practice, there have been (and could be in the future) security bugs in various hypervisors which could allow one virtual machine to affect either the hypervisor or other virtual machines on the same host. Security measures such as sVirt (for KVM/QEMU) are ...


11

When Hyper-V runs as a role on Windows Server 2008 and Windows Server 2008 R2 it's still and hypervisor. It is type 1 (bare metal) in both cases. The trick here is that when you install Hyper-V as a role on Windows Server 2008 R2 you see the Windows Server like a host OS and it is not. The setup converts the original OS in something like a VM and puts the ...


11

Type 2 hypervisors like for example Oracle Virtual Box are great for developer environments where access to multiple operating systems and their variants is required.


8

A couple of free, bare-metal virtualization software options: VMWare ESXi Microsoft Hyper-V Server 2008


8

Edit: I thought this topic was done with months ago, but it has just been revived and now OP is asking for more 'real facts, quoted studies,' etc., so I figured what the heck. Exploits of this nature are: Rare Sensitive in nature and therefore not shared openly, and when they are, the exploits would be patched by the vendor before anyone on this site ever ...


8

Of course it is possible to exploit another VM running on the same hardware, given a working exploit. Additionally, one can exist. Your question cites some recent work showing one. I'm not going to share any specific exploits or PoC here, but I'll gladly say how they can be made. The exploits that are used in this context are naturally different from ...


7

The real benefits of virtualisation are usually; not having to buy extra servers - in your circumstance you've already bought new servers so this point is moot. the ability to have zero-downtime hardware and base-OS updates through live-motion/vmotion - well this is great but requires shared storage - you may or may not have this in place. the ability for ...


7

Whenever your virtualization-solution needs an OS (other then it's own for very basic tasks) to run on, it's "Type 2"-virtualization. It looks like the Windows Server OS will virtualize itself when you install the server roll. The Hypervisor will be started initially on boot which will hand-over the boot process to Windows Server 2008, which is now the ...


6

http://www.xen.org/ for linux?


6

My rule is RAID 10 everywhere, anything else is a compromise - not that I don't have to, or choose to make compromises but my default is always R10 - great protection and performance.


6

Generally I'd expect Raid 10 to show a decent performance boost over Raid 5, but the answer to any question like this is "Test it yourself and find out, because it depends on your exact circumstances, so no one here can give you a definitive answer".


6

The ever quotable Theo de Raddt of the OpenBSD project: You are absolutely deluded, if not stupid, if you think that a worldwide collection of software engineers who can't write operating systems or applications without security holes, can then turn around and suddenly write virtualization layers without security holes. A bit inflammatory but ...


6

Conceptually, the process is simple: start copying all the RAM for a VM from one physical host to another over the network, keeping track of which memory sections you've already copied have been updated after you copied them. Repeat the cycle for the changed RAM until the change set is small, pause the VM, copy the last bits of RAM (and the CPU register ...


6

Okay, Ryan, you made my day. I don't read this forum as much as I used to, but I happened to check in. Red888, you should know up front that I'm a software architect who works on Hyper-V at Microsoft. I assume most people reading this are perfectly capable of clicking on my name link below this and discovering that, or even Googling me, but for this ...


5

Others have explained the differences between the 2 types pretty well. One thing to note is that while it seems like Hyper-V is being installed inside Server 2008, what is actually happening is Hyper-V is being installed at the root partition, and the "host" Server 2008 you're installing on becomes a virtual machine itself. The reason it can see the other ...


5

Do I understand you correctly when I say that you have the bare-metal hypervisor ESXi on the laptop and running with the VM's, but you are looking to access the VM's? You can't do it that way on the laptop. You'll need another computer from which to run the control software like VSphere and/or run remote desktop/ssh/etc. to interface with the VM's directly ...


5

You can hot-add memory with vSphere. However, there is another question you should be asking: "What OS supports the hot addition of RAM?" The guest OS will have to have the ability to see RAM that has been added without a reboot. For example, Windows Server 2003 Enterprise (not standard) supports this, and all Server 2008 versions do as well.


5

Which version of ESXi are you trying to install.. I think the drivers for those are now included in 5.1 (I might be wrong though). Alternatively, you can try to use the Dell customized build of ESXi ISO to install VMWare and see if those include the required drivers you need.


5

You've misconfigured your virtual machine(s) and host. Things to consider: If you have a computationally-heavy process, you may want to disable HyperThreading. HyperThreaded (logical) cores are not the same as physical cores!! Intel E5540 CPUs date back to 2009. They are quad-core CPUs. You'll have 8 physical cores and 8 logical cores (16 total). If ...


4

Can you explain how exactly Intel VT/AMD-V speeds up virtualisation? They make the job of the hypervisor easier, by implementing on CPU techniques VMWare et. al. had to do in their binary translation software. For more details about this, Intel has some nice pages: http://www.intel.com/technology/itj/2006/v10i3/1-hardware/6-vt-x-vt-i-solutions.htm ...


4

I understand why the x86 architecture is/was not by itself virtualisable. That is not true at all. It is virtualisable via Binary translation or more commonly referred as Full virtualisation. You emulate every component of a traditionnal computer with a piece of software sitting on top of an OS. And then I read about Intel VT-x and AMD V which add ...


4

A bare-metal hypervisor (eg ESX, Hyper-V) is simply an operating system designed to control and monitor the access to the hardware. So naturally, a hypervisor within a virtual machine would be controlling and monitoring access to the hardware it has access to. This works because the virtual hardware looks exactly like the real hardware. Paravirtualization ...


4

As nice as the hot-add option is, I wouldn't base a hypervisor choice off of that feature. Are you unable to acquire the downtime needed to make a quick configuration change to size your VM's RAM appropriately?


4

Xen,KVM,Hyper-V,Vmware all support increasing RAM with out restarting. Its done through balloon drivers. check for its support on Guest cat /boot/config-`uname -r` |grep -i balloon In my VM it shows CONFIG_VMWARE_BALLOON=m CONFIG_XEN_BALLOON=y CONFIG_HYPERV_BALLOON=m CONFIG_VIRTIO_BALLOON=m But for ballooning RAM up,you need to set max RAM on ...


4

I had looked at this before but I never found much as far as using it with VMware but it seems XenServer has some good documentation found here for at least one benefit. It speaks mostly of improving network throughput by using irqbalance. http://benpiper.com/2011/08/improving-network-throughput-in-xenserver-using-irqbalance/ Citrix also has a whitepaper on ...


4

This question isn't really on topic here, but ill throw you a bone before it gets closed. I assume by ESX you mean ESXi or the vSphere suite of products. ESX is end of life. I recommend that you visit technet and VMWare online training as a start. Then pick up some books or have your employer send you to training. I recommend Mastering VMWare vSphere 5 ...


4

Check to make sure that the VM and the physical machine don't have the same MAC address or the same IP address set. This sounds suspiciously like either a duplicate IP issue, or an accidental arp poisoning.



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