The document discusses the advantages of using Xen for cloud computing, highlighting its architecture, security benefits, and integration with cloud orchestration tools like OpenStack and CloudStack. It also introduces XCP, an open-source cloud platform based on Citrix XenServer, and outlines Project Kronos, which allows Debian and Ubuntu users to access XCP's capabilities. Overall, Xen is presented as a flexible and secure option for enterprise cloud solutions.

1. Why Choose Xen For Your Cloud?
Todd Deshane
Build an Open Source Cloud Day - Boston
December 9, 2011

2. Who am I?
● Xen.org Technology Evangelist
● Involvement with Xen started in 2003 as graduate student
● Co-author of research paper:
○ "Xen and the Art of Repeated Research"
○ USENIX 2004
● Co-author of the "Running Xen" book
● XCP/cloud integrator and tester

3. Outline
● Xen in the cloud history
● Xen architecture and security benefits
● XCP
● Project Kronos

4. Xen (in the Cloud) History

5. Global Public Computing
"This dissertation proposes a new distributed computing
paradigm, termed global public computing, which allows any
user to run any code anywhere. Such platforms price
computing resources, and ultimately charge users for resources
consumed."
- Evangelos Kotsovinos, PhD dissertation, 2004

6. Xen (in the Cloud) History

7. Xen Architecture

8. Xen Architectural Security Advantages
● Small, clean, disaggregatable trusted computing base
○ Xen hypervisor (guest scheduling, virtual hardware
abstraction)
○ Management/control domain can be broken up into
multiple domains
○ Driver domains can isolate hardware functions (e.g.
network or storage driver domains)
● Well-defined trusted computing base
○ Need only trust hypervisor and compartmentalized
management, control, and driver domains
○ No extra services in hypervisor layer
○ Full OS not needed (as is with type-2 hypervisor)

9. Xen Cloud Platform (XCP)
● Open source version of Citrix XenServer
○ http://wiki.xen.org/wiki/XCP/XenServer_Feature_Matrix
● Enterprise-ready server virtualization and cloud platform
● Built-in support and templates for Windows and Linux
guests
● Datacenter and cloud-ready management API
○ XenAPI (XAPI) is fully open source
○ CloudStack and OpenStack integration
● Open vSwitch support built-in

10. XCP Architecture

11. Xen API (XAPI)
● VM lifecycle: live snapshots, checkpoint, migration
● Resource pools: live relocation, auto configuration, disaster
recovery
● Flexible storage, networking, and power management
● Event tracking: progress, notification
● Upgrade and patching capabilities
● Real-time performance monitoring and alerting

12. XAPI Class Diagram

13. Open vSwitch
● Software switch, similar to:
○ VMware vNetwork Distributed Switch
○ Cisco Nexus 1000V.
● Distribution agnostic. Plugs right into Linux kernel.
● Reuses existing Linux kernel networking subsystems.
● Backwards-compatible with traditional userspace tools.
● Free and Open Source http://openvswitch.org/

14. Why use Open vSwitch with Cloud?
● Multi-tenancy
● Automated control
● Monitoring and QoS

15. XCP Management Options
● xe is tab-completable, XAPI frontend command line tool
● Desktop GUIs
○ Citrix XenCenter (Windows-only)
○ OpenXenManager (open source cross-platform
XenCenter clone)
● Web interfaces
○ Xen VNC Proxy (XVP)
■ lightweight VM console only
■ user access control to VMs (multi-tenancy)
○ XenWebManager (web-based clone of
OpenXenManager
● XCP Ecosystem: http://wiki.xen.org/xenwiki/XCP_Projects

16. OpenXenManager

17. Xen VNC Proxy (XVP)

18. Xen VNC Proxy (XVP)

19. XCP and Cloud Orchestration Tools
● XCP and OpenStack
● XCP and CloudStack
● XCP and OpenNebula

20. XCP and OpenStack
First commercial OpenStack cloud
(Internap): XCP-based

21. XCP and CloudStack

22. XCP and OpenNebula

23. Project Kronos
● Port of XCP's XAPI toolstack to Debian and Ubuntu dom0
● Gives users the ability to install Debian or Ubuntu, then
apt-get install xcp-xapi
● Provides Xen users with the option of using the same API
and toolstack that XCP and XenServer provide
● Early adopters can try new changes to the XAPI before they
get released in mainstream XCP and XenServer versions
● Now much easier to build tools outside of an SDK VM

24. Project Kronos Overview

25. Project Kronos Overview
Xen API (XAPI)
Hypervisor

26. XCP vs. Project Kronos
XCP Project Kronos
Pros Pros
● Isolation of cloud VM ● Simple install
● Security properties ● Flexibility
● Pre-package + appliance ● Simpler overall
Cons Cons
● Slightly more complex ● Less isolation
● Less flexible ● Cloud node is a potential
entry point to Dom0

27. Summary
● Xen has many great advantages for cloud use
● Xen is widely used in the cloud
● XAPI cloud-ready for use with cloud orchestration
○ fully open source
● XCP and Project Kronos provide flexibility and choice

28. Thank You!