Switch KVM Stacks

WARNING:

Oracle Linux 7 is now in Extended Support. See Oracle Linux Extended Support and Oracle Open Source Support Policies for more information.

Migrate applications and data to Oracle Linux 8 or Oracle Linux 9 as soon as possible.

You can switch from one KVM stack to another KVM stack, if required.

The KVM stacks define the versions of user space packages that you can use to manage virtual machines on Oracle Linux. To take advantage of newer functionality available in more recent user space packages, you must install UEK.

The Default KVM Stack is compatible with both RHCK and UEK. The Default KVM Stack is available from the standard Oracle Linux package repositories or ULN channels. If you require RHCK, you can only use the Default KVM Stack.

The Oracle KVM Stack, which includes more KVM features than the default stack, requires UEK to be running on the host system and that the system is subscribed to the appropriate yum repositories or ULN channels.

Switching the KVM stack on an Oracle Linux system involves removing one version of the KVM stack and then replacing it with another version of the KVM stack.

Caution:

Guests instances that were created by using one KVM stack might not be compatible and might not start after switching to another KVM stack.

For instructions on how to switch KVM stacks on Oracle Linux 7 systems with UEK, see these topics:

• Switch Default Stack to Oracle KVM Stack
• Switch Oracle KVM Stack to Default Stack

Note:

For details about the KVM stacks included in virtualization packages from a yum repository or ULN channel, see KVM Repositories and Channels: Yum and ULN.

Switch Default Stack to Oracle KVM Stack

The following information describes how Oracle Linux 7 UEK users can switch from the Default KVM Stack to the Oracle KVM Stack.

Caution:

Guest instances that were created by using the Default KVM Stack might not be compatible and might not start after switching to the Oracle KVM Stack.

What Do You Need?

• Oracle Linux 7 UEK system with the Default KVM Stack packages installed.
• Administrator privileges.

Steps

Follow these steps to switch from the Default KVM Stack to the Oracle KVM Stack.

1. Remove any packages from the existing Default KVM Stack, for example:

   sudo yum remove libvirt* qemu* virt-install

2. Enable the ol7_kvm_utils yum repository or ol7_<arch>_kvm_utils ULN channel.

   See Enable the Yum Repository or Subscribe to ULN Channels as appropriate.

3. Install the required virtualization packages from the ol7_virt_utils yum repository or ol7_<arch>_virt_utils ULN channel:

   sudo yum install libvirt qemu-kvm virt-install

Switch Oracle KVM Stack to Default Stack

The following information describes how Oracle Linux 7 UEK users can switch from the Oracle KVM Stack to the Default KVM stack.

Caution:

Guests instances that were created by using the Oracle KVM Stack might not be compatible and might not start after switching to the Default KVM stack.

What Do You Need?

• Oracle Linux 7 UEK system with the Oracle KVM stack installed.
• Administrator privileges.

Steps

Follow these steps to switch from the Oracle KVM Stack to the Default KVM Stack.

1. Remove any packages from the existing Oracle KVM Stack, for example:

   sudo yum remove libvirt* qemu* virt-install

2. Disable the ol7_virt_utils yum repository or ol7_<arch>_virt_utils ULN channel.
3. Install the required virtualization packages from the ol7_latest yum repository or ol7_<arch>_latest ULN channel. For example:

   sudo yum --disablerepo="*" --enablerepo="ol7_latest" install libvirt qemu-kvm virt-install