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31

I can see two possible reasons for you to be seeing those file sizes: Sparse files File system corruption Sparse files is a feature on some file systems whereby you can create a file with holes in it. No physical space is allocated for the holes. Reading across the holes will return NUL bytes all the way. If the reason for what you are seeing is sparse ...


17

If you are running server 2012 then you already have access to hyper-v. The free hyper-v should serve your needs, you can run the GUI from any client or the 2012 server. This would also get you shared nothing migrations if you can't afford a san. http://blogs.technet.com/b/keithmayer/archive/2012/09/07/getting-started-with-hyper-v-server-2012-hyperv-...


11

You can't use switch port security on the Cisco since all the VMs will be sharing a physical switch port. And you can't use Linux iptables because the traffic is being bridged, not routed, through the hypervisor machine. But you can emulate switch port security on the hypervisor with Linux ebtables, which is a lesser-known layer 2/3 firewall on the Linux ...


9

This is how I currently do installs of Windows with virtio drivers at install: Create the new VM with a genuine Windows installation ISO image. I cannot guarantee that anything will work if you use a pirated copy of Windows or if your ISO image download is incomplete or corrupt. Choose to customize the machine configuration before install. Select the ...


9

You can use VMware ESXi for free... You don't necessarily need to use the web interface, and the product works very well with the thick client. Or better, buy a vSphere Essentials license ($500) and have the ability to manage up to 3 host servers. This will give you vCenter capabilities and the Web interface if you wish to utilize it. Either way, the cost ...


7

Online Method (using qemu, libvirt, and virtio-block) Perform the following from the KVM hypervisor. Increase the size of the disk image file itself (specify the amount to increase): qemu-img resize <my_vm>.img +10G Get the name of the virtio device, via the libvirt shell (drive-virtio-disk0 in this example): virsh qemu-monitor-command <my_vm&...


7

It's a (known) bug. Workaround: Change the display from 'default' to 'cirrus'. You can find this setting under hardware > display. Kind regards, Ilias el Matani


6

Most current hypervisors that run on Intel hardware use CPUID leaves 0x40000000 et seq. to pass information about the hypervisor from host to guest. KVM, Xen, VMware and Hyper-V all use this method. This is in addition to the hypervisor feature flag set in CPUID leaf 0x1, which indicates that the machine is a virtual machine. It's therefore trivial for a ...


6

Use proxmox, an hypervisor based on KVM (other containers types also supported) all integrated via a web interface. We use this on dell rack servers and it is just perfect for small companies. You can also buy paid support. Note that Proxmox is based on RedHat long-term support kernels, which is synonym for stability and good driver support for servers. ...


6

You have no way of predicting what the device names or IDs will be after a significant hardware change (virtual hardware in this case, from Xen to KVM). Linode is the only entity here who knows what's going to change and how you should proceed if you upgrade. With that said, don't do this. You're forcing yourself to take an outage. If it breaks, you'll be ...


6

The problem is the way you compute a file size. One way it is look the offset of the last byte (like ls). The other way is to sum really allocated blocks (like du). What you see if probably a file with data written at very large offset. Meaning that major parts of your file address space is not allocated. But you can still read it.


5

It's difficult to troubleshoot remotely with limited information. But I'd like to try. First, just a guess. Usually the DEVICE name is eth0 or eth1, not eth01. This might explain the "invalid argument error". Make sure you are dealing with the right NIC by ifconfig -a or ip link in the VM. Another suspect is the static route. It should have 13 items in ...


4

I know that's an old question but I've found it while googling for the solution and hope it may help someone else. As for today it is possible to resize the hard drive on the machine. I've found a working way here: https://bugzilla.redhat.com/show_bug.cgi?id=648594 The following steps must be performed: Find out a file name and KVM device name of the ...


4

Here is a serious problem: <domain type='qemu'> This should appear as: <domain type='kvm'> If this is set to qemu, then qemu will run the machine without any sort of hardware virtualization support. Without this option set, qemu will not be told to enable KVM hardware acceleration. This is fine for, e.g. emulating non-Intel processors, but ...


4

The only thing you are missing is to quiesce the guest filesystem before taking the snapshot, to ensure that it is consistent. This can be done with virsh domfsfreeze if you are using libvirtd. For example, the order of operations is: # Freeze guest filesystems virsh domfsfreeze $VM_NAME # Create snapshot qemu-img create -f qcow2 -b $VM_NAME.qcow2 ...


4

Virtio is a para-virtualized driver, which means the os and driver are aware that it's not a physical Device. The driver is really an API between the guest and the hypervisor so it's linkspeed is totally disconnect from any physical device or Ethernet standard. This is a good thing as this is faster than the hypervisor pretending to be a physical device and ...


4

You created your guest with virsh create (or its equivalent). This creates transient domains, which are deleted when they power off. To create persistent domains, use virsh define instead. These remain defined after they are powered off or destroyed, and can be started again at any time.


4

It's probably a backup process or something storage-impacting happening at the host level. This is outside of your control and you should push the VPS provider for a solution. If they can't resolve, consider going elsewhere.


3

It's entirely possible that if you're using pfSense 2.2 or later, you're being affected by this. Symptoms would include: Slowness for other VMs hosted on the KVM platform if they need to access a network resource which is on the other side of one of the router interfaces on the pfSense router Physical machines which need to access something across the ...


3

For offline configuration: To increase the number of CPUs: virsh setvcpus <vm_name> <vcpu_count> --config If you get an error that you exceeded the maximum number, first do: virsh setvcpus <vm_name> <vcpu_count> --config --maximum Then repeat the above: virsh setvcpus <vm_name> <vcpu_count> --config To increase ...


3

Sorry for digging out old topic, but I found out this is possible: The problem with branded media is that KVM's BIOS VM ships with diffrent ACPI tables. Installer on the other hand validates it. In the time of writing this I am using Debian 8 with virtlib 1.2.9 and qemu-system-x86 1.7.0 (qemu-kvm). So simply you need to have matched ACPI (dmidecode -t 0 ...


3

A more "official"[1] way to do this is to create a hook script as described at the libvirt website: http://wiki.libvirt.org/page/Networking#Forwarding_Incoming_Connections ... basically this script will be invoked when a KVM guest is booted-up. The script itself will add the appropriate iptable rules (similar to Isaac Sutherland's answer above) with the '...


3

According to the community wiki (https://help.ubuntu.com/community/32bit_and_64bit), Ubuntu itself is limited to about 1TB of memory. I would assume this means that it has trouble assigning more memory than that to a guest OS.


3

If you need to backup your vm configuration using virsh you can use the following command virsh dumpxml vmname > vmname.xml If you need to move your vm to other server, you can dump your vm config and transfer the xml, if you are using files as backend storage for your vm you can copy the files to other server using scp or rsync, when you copied the ...


3

You should be able to image your disks from a snapshot: First you wil need to make sure the Vm is not running: virsh suspend vm Now you can create a snapshot make sure to adjust the size 100M and the name vm-root-snapshot to your own needs. lvcreate -L 100M -n vm-root-snapshot -s /dev/sysvg/vm-root After this you can start the VM again. virsh resume vm ...


3

Why? Because it's a bug in ganeti gnt-network connect -N link=vbr0 net1 default


3

Apparently, the proper method was virsh snapshot-delete prod --metadata snap (This command can be found on the wiki. I tried it before asking here but it failed due to a typo that has been corrected since.) I don't know what it does that is not covered by removing the .xml file while libvirtd is down. Maybe the only difference is that stopping libvirtd ...


3

I can't say how well Windows works with KVM, but I think it's worth testing. There are PV drivers available for Windows. It wouldn't be so bad to setup a VM and run some benchmarks. KVM is nice because it's built into the kernel, unlike Xen. Performance is about the same. I find it easy to use via libvirt and the "Virtual Machine Manager" GUI. It can ...


3

As others already suggested, if you already have a Windows Server license, you thus have an enterprise-grade virtualization platform in your possession. If it is a Standard edition, then you can use it this way: (1) install one instance of Windows Server on a physical server with up to two physical sockets (number of cores doesn't matter, matter processor ...


3

Not at present. It looks like CPU hotplug used to be possible in QEMU, but the patch is old and crusty, never worked with windows guests, and not shipped natively anymore. http://www.linux-kvm.org/page/CPUHotPlug



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