Installation guide

Glossary
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can run multiple, unmodified virtualized guest Windows and Linux
operating systems. The KVM hypervisor in Red Hat Enterprise
Linux is managed with the libvirt API and tools built for libvirt, virt-
manager and virsh.
KVM is a set of Linux kernel modules which manage devices,
memory and management APIs for the Hypervisor module itself.
Virtualized guests are run as Linux processes and threads which are
controlled by these modules.
Red Hat Enterprise Linux KVM hypervisors can be managed by the
Red Hat Enterprise Virtualization Manager as an alternative to libvirt.
LUN A Logical Unit Number (LUN) is a number assigned to a logical unit (a
SCSI protocol entity).
MAC Addresses The Media Access Control Address is the hardware address for a
Network Interface Controller. In the context of virtualization MAC
addresses must be generated for virtual network interfaces with each
MAC on your local domain being unique.
Migration Migration is the term for the process of moving a virtualized guest
from one host to another. Migration can be conducted offline (where
the guest is suspended and then moved) or live (where a guest is
moved without suspending).
Offline migration
An offline migration suspends the guest then moves an image of the
guest's memory to the destination host.
Live migration
Live migration is the process of migrating a running guest from one
physical host to another physical host.
Para-virtualization Para-virtualization is only available in Red Hat Enterprise Linux 5.
Para-virtualization uses software mechanisms to share devices and
system resources with specially-designed kernels or newer kernels
with the PV-opts features.
Para-virtualized See Para-virtualization,
Para-virtualized drivers Para-virtualized drivers are device drivers that operate on fully
virtualized Linux guests. These drivers greatly increase performance
of network and block device I/O for fully virtualized guests.
PCI passthrough The KVM hypervisor supports attaching PCI devices on the host
system to virtualized guests. PCI passthrough allows guests to
have exclusive access to PCI devices for a range of tasks. PCI
passthrough allows PCI devices to appear and behave as if they were
physically attached to the guest operating system.
Physical Functions Physical Functions (PFs) are full PCIe devices that include the SR-
IOV capabilities. Physical Functions are discovered, managed, and
configured as normal PCI devices. Physical Functions configure and
manage the SR-IOV functionality by assigning Virtual Functions.