XenServer is a hypervisor developed by the Linux Foundation that allows multiple operating systems to run concurrently on the same computer hardware. It uses a microkernel design with four main layers: the hardware layer, the hypervisor layer, the virtual machine layers, and various software layers that provide services and management of virtualized resources across networks, storage, and applications. The hypervisor sits above the physical hardware and is responsible for sharing resources and enforcing access controls.

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

4. Architecture of Xenserver

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

6. SIMPLE XENSERVER ARCHITECTURE

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.

8. Hardware:

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.

11. Hypervisor layers:
The Multi-Server
Approach
Microkernels are
minimalistic
operating system
kernels providing only
elementary services
like process
management, inter-
process
communication, and
memory resp.
exception support

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.

14. Virtual layers:

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.

19. Presented by,
N .Ramya
THANK YOU