Hypervisor-specific information

Red Hat Enterprise Linux 8.4 LPAR mode z/VM guest KVM guest

This publication provides information for Linux® in LPAR mode and for Linux as a guest of z/VM® or KVM.

In this publication, topics that apply to all hypervisor environments, are marked with the icons that are shown at the beginning of this topic. Lesser differences between environments are marked with the applicable icon within the description as follows:

Linux in LPAR mode

LPAR mode Processor Resource/Systems Manager (PR/SM) technology always divides IBM Z® hardware resources into one or more logical partitions (LPARs). Linux in LPAR mode runs directly in an LPAR.

Linux on z/VM

z/VM guest The z/VM hypervisor is an IBM Z operating system that can run in an LPAR and provide IBM Z virtual machines. Linux on z/VM runs as a guest in a z/VM guest virtual machine.

z/VM virtualizes z/Architecture® and Z devices to its guests, so most of what applies to Linux in LPAR mode also applies to Linux as a z/VM guest.

Depending on your z/VM virtual machine definition and on your z/VM version and service level, a particular z/VM guest might not provide all of the described features. See ibm.com/vm/newfunction/index.html about upcoming and available new function for z/VM.

For information that exclusively applies to Linux on z/VM, see z/VM virtual server integration.

Linux on KVM

KVM guest Linux in LPAR mode can be set up as a KVM host that provides KVM virtual servers. Linux on KVM runs as a guest in a KVM virtual server. For information about managing KVM virtual servers, see the documentation of your KVM host distribution and KVM Virtual Server Management, SC34-2752.

KVM virtual servers on Z present many mainframe devices as generalized virtio devices to their guests. To Linux, these virtio devices resemble virtio devices on other hardware architectures more than the underlying mainframe devices. Therefore, entire parts and chapters of this publication do not apply to Linux on KVM.

Depending on your KVM host and on your virtual server configuration, a particular KVM guest might not provide all of the described features.

For information that exclusively applies to Linux on KVM, see KVM virtual server integration.