2. Introduction
XenServer was developed by Linux foundation and
supported by Intel
It is a hypervisor using a Microkernal design,providing
services that allow multiple computer operating system
to execute on the same computer hardware concurrently.
3. Setting up of xenserver
Xenserver Architecture
Hardware layer
Hypervisor layer
Virtual machine layers
5. Architecture:
The architectural implementation of the
hypervisor: this includes discussions like “my
hypervisor is thinner than yours” etc. The hardware
assists (Intel-VT, AMD-V) dilemma: “my hypervisor
uses cpu hardware extensions to do what you do in
software so it’s faster than yours” or viceversa. The
paravirtualization dilemma: “my hypervisor can
support this modified guest hence it’s (or it will be)
faster than yours” etc
7. Hardware layer:
The hardware layer is the sphere that contains a
hypervisor and its underlying physical hardware.
The hardware layer participates in the Xen App
infrastructure by running the OS resources and
keeping VM workloads highly available.
9. Hypervisor:
Very large system support
4 TB; >255 CPUs
Reliability, Availability, Scalability enhancements
CPU Pools for system partitioning
Page sharing enhancements
Hypervisor emergency paging / compression
New “xl” lightweight control stack
Memory Introspection API
Enhanced SR-IOV support
Software-implemented Hardware Fault Tolerance
10. Hypervisor layer:
On top of the hardware layer, it is responsible for both
sharing of hardware resource and the enforcement of
mandatory access control rules based on the available
hardware resources.
12. VIRTUALIZATION:
Virtualization is an approach that was developed by
the pioneers of computing systems. It involved using
unused computing resources to create an artificial, but
useful, view of system capabilities.
13. VIRTUAL MACHINE:
Virtual Machine Hardware
Virtuozzo virtual machine works like a usual standalone
computer.
By default, virtual machines are created with the following
virtual hardware:
1 VirtIO SCSI HDD, expanding,
1 CD-ROM (IDE for Windows and Debian guests, VirtIO
SCSI for Linux guests except Debian),
1 VirtIO network adapter, bridged,
32MB video card.
15. Layers:
Layer 1:
Allows applications to
work with remote client
devices without change,
even though those remote
devices were never been
thought of or available
when the application was
written. This is
called access
virtualization. Xen
Desktop from Citrix is an
example of products that
work in this layer of
virtualization.
Layer 2:
Allows applications written
for one OS version or OS to
happily execute in another
environment; this
environment can be a new
OS version or an entirely
different OS. This is
called application
virtualization.
16. Layer 3:
Allows one system to
support workloads as if it
was many systems, or
allows one workload to run
across many systems as if it
was a single computing
resource. This is
called processing
virtualization .
Layer 4:
Allows workloads to access
storage without having to
know where the data is
stored, what type of device
is storing the data, or
whether the storage is
attached directly to the
system hosting the
workload, to a storage
server just down the LAN,
or to storage in the cloud.
This is called storage
virtualization.
17. Layer 5:
Allows systems to work
with other systems safely
and securely, without
having to care too much
about the details of the
underlying network. This
is called network
virtualization .
Layer 6:
Allows IT administrators
and operators to easily
monitor and manage
virtual environments
across boundaries. The
boundaries can include
the physical location of
systems; OSes in use;
applications or workloads
in use; network topology;
storage implementation;
and how client systems
connect to the
applications. This is
called management of
virtualized environments .
18. Layer 7:
Monitors and protects all of the other layers of
virtualization so that only authorized use can be made
of the resources. Yes, this is called security for
virtualized environments in the model.
Earlier this year, we released Xen 4.1
I just put up the feature list, but I wont go through it in detail. I did want to point out that the focus of this release was on
Support for large systems and easier management of large systems with CPU poolks
As well as on security
And that is starting a trend to optimize the hypervisor for cloud use cases