Start, Shutdown, Reboot, or Remove KVM

KVM: Start Instance

The following information describes how to start a KVM instance that's shut down on a local or remote host using the virsh start command.

What Do You Need?

Administrator privileges.
Name of the inactive KVM instance.
For remote KVM instances, the following is required to complete the remote example shown in Step 1.
- The host IP address where the inactive KVM instance resides.
- Root privileges to the host.
- SSH connection protocol port enabled.
- The qemu-kvm virtualization package is installed. For details about virtualization packages, see KVM Virtualization Packages: Recommended.

Steps

Follow these steps to start an inactive KVM on a host system using the virt start command:

Perform one of the following:
- For local KVM, use the virt-start command as follows:
```
sudo virsh start KVM_Guest_Name
```
  Example output:
```
Domain 'KVM_guest_name' started
```
- For remote KVM, use the virt start command and the SSH connection protocol as follows:
```
sudo virsh -c qemu+ssh://root@host_ip_address/system start Remote_KVM_guest_name
```
  Example output:
```
root@host_ip-address's password:

Domain 'remote_KVM_guest_name' started
```

KVM: Shut Down Instance

The following information describes how to shut down an active KVM instance on a local or remote host using the virsh shutdown command. It also describes how to force an unresponsive KVM instance on a host to shut down using the

virsh
        destroy

command.

Note:

The virsh destroy command doesn't delete or remove the KVM configuration or its disk images. It only forces the running KVM instance to shut down, similarly to pulling the power cord on a physical machine. However, in unique cases, the virsh destroy command might cause corruption to the KVM file system, so using this command is only recommended when all other shutdown methods have failed.

What Do You Need?

Administrator privileges.
Name of the active or unresponsive KVM instance.
For remote KVM instances, the following is required to complete the remote example shown in Step 1.
- The host IP address where the KVM instance resides.
- Root privileges to the host.
- SSH connection protocol port enabled.
- The qemu-kvm virtualization package is installed. For details about virtualization packages, see KVM Virtualization Packages: Recommended.

Steps

Follow these steps to shut down a KVM instance on a host system using either the virt shutdown command or the virt destroy command.

Perform one of the following:
- Graceful KVM Shutdown – Perform either of the following:
  - For a local KVM, use the virt shutdown command as follows:
```
sudo virsh shutdown KVM_Guest_Name
```
    Example output:
```
Domain 'KVM_guest_name' is being shutdown
```
  - For a remote KVM, use the virt shutdown command and the SSH connection protocol as follows:
```
sudo virsh -c qemu+ssh://root@host_ip_address/system shutdown Remote_KVM_guest_name
```
    Example output:
```
root@host_ip-address's password:

Domain 'remote_KVM_guest_name'is being shutdown 
```
- Forceful KVM Shutdown - Use the virt destroy command on an unresponsive KVM instance as follows:
```
sudo virsh destroy KVM_Guest_Name
```
  Example output:
```
Domain 'KVM_guest_name' destroyed
```

KVM: Suspend or Resume Instance

The following information describes how to suspend an active KVM instance on a local or remote host using the virsh suspend command. It also describes how to resume a suspended KVM instance on a host using the virsh resume command.

What Do You Need?

Administrator privileges.
Name of the active or suspended KVM instance.
For remote KVM instances, the following is required to complete the remote example shown in Step 1.
- The host IP address where the KVM instance resides.
- Root privileges to the host.
- SSH connection protocol port enabled.
- The qemu-kvm virtualization package is installed. For details about virtualization packages, see KVM Virtualization Packages: Recommended.

Steps

Follow these steps to suspend or resume a KVM instance on a host system.

Perform one of the following:
- Suspend KVM – Perform either of the following:
  - For a local KVM, use the virt suspend command as follows:
```
sudo virsh suspend KVM_Guest_Name
```
    Example output:
```
Domain 'KVM_guest_name' suspended
```
  - For a remote KVM, use the virt suspend command and the SSH connection protocol as follows:
```
sudo virsh -c qemu+ssh://root@host_ip_address/system suspend Remote_KVM_guest_name
```
    Example output:
```
root@host_ip-address's password:

Domain 'remote_KVM_guest_name' suspended
```
- Resume KVM - Use the virt resume command on an suspended KVM instance as follows:
```
sudo virsh resume KVM_Guest_Name
```
  Example output:
```
Domain 'KVM_guest_name' resumed
```

KVM: Reboot Instance

The following information describes how to reboot a KVM instance on a local host using the virsh reboot command.

Note:

Rebooting a KVM can be helpful with various problems and might even be necessary to complete some configurations.

What Do You Need?

Administrator privileges.
Name of the KVM instance.

Steps

Follow these steps to reboot a KVM instance on a host system.

Type:
```
sudo virsh reboot My_KVM_Guest[--mode method]
```
Where:
- [--mode method] is optional. The mode method option lets you specify an alternative shutdown method such as acpi or agent.
Example output:
```
Domain My-KVM_Guest is being rebooted
```

KVM: Remove KVM Instance

The following information describes how to remove a KVM instance on a host system using the virsh undefine command. It also describes how to optionally remove the storage artifacts associated with a KVM instance.

What Do You Need?

Administrator privileges.
KVM information and actions required:
- KVM instance name.
- KVM storage is not in use by other KVMs.
- Removal of any KVM snapshots. To remove snapshots associated with KVM instance, use the virsh snapshot-delete.
- KVM storage file path. To identify the storage file path associated with a KVM instance, use the virsh dumpxml command. For example:
```
 sudo virsh dumpxml --domain My_KVMGuest_Name | grep 'source file'
```
  Example output:
```
<source file='/home/testuser/.local/share/libvirt/images/My_KVMGuest_Name-1.qcow2'/>
```
- KVM instance is shutdown. For details, see KVM: Shut Down Instance
- (Optional) Back up all important data on KVM instance. If required, see Clone: Existing KVM Instance.

Steps

Follow these steps to remove a KVM instance from a host system.

To delete the KVM instance, type:
```
sudo virsh undefine My_KVMGuest_Name                        
```
The virsh undefine command removes all configuration information about the KVM instance from libvirt. Note that the associated KVM storage artifacts such as virtual disks remain intact.
(Optional) To delete the storage artifacts such as virtual disks associated with the KVM instance (removed in Step 1), use the rm command followed by the storage path.
For example:
```
sudo rm /home/testuser/.local/share/libvirt/images/My_KVMGuest_Name-1.qcow2                        
```