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====== KVM Command Line ======

"virsh" shell for KVM.

=== List All Domain on KVM ===
<code bash>
virsh list --all
</code>

=== Define or use .xml ===
<code bash>
virsh define <xyz.xml>
</code>

=== Start KVM ===
<code bash>
virsh start <xyz>
</code>

=== Edit Guest .xml ===
<code bash>
virsh edit xyz
</code>

=== List VNC Information ===
<code bash>
virsh vncdisplay xyz
</code>

[[http://libvirt.org/formatdomain.html|Domain Format in KVM]]

==== Test your bootable USB on kvm ====
In order to test your USB using KVM use following command.
<code bash>
qemu-kvm -hdb <device> 
</code>
In my case device was "/dev/sdb".

==== Converting Existing Image ====
=== Converting VMWARE image for KVM ===

use following command.
<code bash>
qemu-img convert own_Cloud.vmdk -O qcow2 ownCloud.qcow
</code>

=== Converting .ova to KVM image ===
what is ova - Open Virtualization Format

[[http://communities.vmware.com/community/vmtn/server/vsphere/automationtools/ovf | Download - Open Virtualization Format Tool ]]

Install it, which give you command "ovftool".

<code bash>
ovftool -tt=vmx Amazon-EC2-VM-Import-Connector.ova amazon_kvm
</code>

converting .ova is just easy\\
some times ovftool failing\\

<html>
<span style="color:red;font-size:150%;">If Above does not work just do</span>
<p><span style="color:red;font-size:150%;"> tar -xvf Amazon-EC2-VM-Import-Connector.ova </span></p>
</html>

Now follow [[ #Converting VMWARE image for KVM | Converting VMWARE image for KVM ]]


==== Create New KVM Guest using existing Image ====

<code bash>
virt-install --name=own_cloud --arch=x86_64 \
--vcpus=1 --ram=512 --os-type=linux --os-variant=sles11 \
--hvm --connect=qemu:///system --network bridge:br0 \
--import --disk path=/home/vmware/ownCloud_in_a_box-1.0.4/ownCloud.qcow \
--accelerate --vnc --noautoconsole --keymap=us
</code>

==== Backup ====

=== Creating snapshot of Machine ===
**NOTE :** \\
 - This will turn off your Guest.\\
 - it will create snapshot in current working directory.\\
 - Use `virsh pwd` to check your current working directory.

<code bash>
virsh save <Domain Name> <fileName>
</code>
==== Quick Command Ref. ====

<code text>
help	 Prints basic help information.
list	 Lists all guests.
dumpxml	 Outputs the XML configuration file for the guest.
create	 Creates a guest from an XML configuration file and starts the new guest.
start	 Starts an inactive guest.
destroy	 Forces a guest to stop.
define	 Outputs an XML configuration file for a guest.
domid	 Displays the guest's ID.
domuuid	 Displays the guest's UUID.
dominfo	 Displays guest information.
domname	 Displays the guest's name.
domstate	 Displays the state of a guest.
quit	 Quits the interactive terminal.
reboot	 Reboots a guest.
restore	 Restores a previously saved guest stored in a file.
resume	 Resumes a paused guest.
save	 Save the present state of a guest to a file.
shutdown	 Gracefully shuts down a guest.
suspend	 Pauses a guest.
undefine	 Deletes all files associated with a guest.
migrate	 Migrates a guest to another host.
</code>

<code text>
setmem	 Sets the allocated memory for a guest.
setmaxmem	 Sets maximum memory limit for the hypervisor.
setvcpus	 Changes number of virtual CPUs assigned to a guest.
vcpuinfo	 Displays virtual CPU information about a guest.
vcpupin	 Controls the virtual CPU affinity of a guest.
domblkstat	 Displays block device statistics for a running guest.
domifstat	 Displays network interface statistics for a running guest.
attach-device	 Attach a device to a guest, using a device definition in an XML file.
attach-disk	 Attaches a new disk device to a guest.
attach-interface	 Attaches a new network interface to a guest.
detach-device	 Detach a device from a guest, takes the same kind of XML descriptions as command attach-device.
detach-disk	 Detach a disk device from a guest.
detach-interface	 Detach a network interface from a guest.
</code>

==== FU Commands ====

=== Create Disk ===
create disk of size 10G
<code bash | for dynamic allocation>
qemu-img create -f raw vdisk.img 10G 
</code>
OR
<code bash | preallowcation>
dd if=/dev/zero of=vdisk.img bs=1G count=0 seek=[NUMBER_OF_GB]
</code>

==== How to allow network access to KVM Guest ====

Modify guest.xml file and listen variable.
<code bash | vi /etc/libvirt/qemu/Archlinux.xml>
<graphics type='vnc' port='-1' autoport='yes' listen='192.168.1.4' passwd='testing1'/>
</code>

==== Extract folder from KVM Guest Image ====
This appears to be the far easy solution than I thought.\\
[[http://libguestfs.org/virt-copy-out.1.html|Link to official Document]]

For RHEL you require the following packages installed.
  * libguestfs-tools
  * libguestfs-xfs  # if guest filesystem is XFS.

<code bash>
mkdir test
virt-copy-out -a machine2.qcow2 /metadata/testing/users test/
</code>

==== Image File explorer ====
This is a simple way to extract or access files.\\
Scan and assign the dev node.
<code bash>
losetup --partscan --find --show sdcard.img
</code>

List all the block devices, including newly scanned.
<code bash>
lsblk --fs
</code>

Mounting the file system
<code bash>
mount /dev/loop0p2 /mnt/sdcard
</code>

Once unmounted remove the lo drive.
<code bash>
losetup --detach-all
</code>