5. We propose a system that can execute code supplied
by an untrusted user, yet can charge this user for all
resources consumed by the computation. Such
servers could be deployed at strategic locations
throughout the Internet
Xenoservers: Accounted execution of untrusted code
IEEE Hot Topics in Operating Systems VII
March 1999
6. Why use Xen today?
• Open Source with a large community and ecosystem
• Mature and “Cloud Proven”
ᵒAmazon, Rackspace and many others
• Probably 10-12 Million OpenSource Users
ᵒe.g. 3 x people on Debian have used Xen in the last 30 days vs KVM
ᵒ12% of Ubuntu Servers hosted on Xen
• Type 1 hypervisor
ᵒReduced TCB
ᵒBest security, isolation, performance, scalability mix
• ParaVirtual OPerationS now in Linux
12. How can I install it?
Xen Cloud Platform (XCP) Citrix XenServer
• Includes Xen and XAPI • Includes Xen and XAPI
• Supported by Xen Community • Fully Supported by Citrix
• Fully OpenSource • Free edition
• xcp-xapi package ᵒWindows VMs
ᵒPool based Live Migration
ᵒDebian Wheezy & Ubuntu Precise
ᵒHopefully in Fedora soon
• http://xen.org/products/cloudxen.html http://citrix.com/xenserver/download
29. Get Involved
• Ask a question
• Ask on the mailing list
• Read the documentation
ᵒhttp://docs.openstack.org/trunk/openstack-compute/admin/content/introduction-to-
xen.html
ᵒ[TODO – getting started doc]
• Look on the wiki
ᵒhttp://wiki.openstack.org/XenServer
ᵒhttp://wiki.openstack.org/HypervisorSupportMatrix
30. Using XenServer within
Rackspace Cloud Servers
Chris Behrens
chris.behrens@rackspace.com
OpenStack Summit, San Diego
October 2012
3
0
31. Intro to Cloud Servers
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32. Intro to Cloud Servers
Overview
• Public Cloud product under Rackspace‟s Open Cloud portfolio
• First Gen
– Code originated from Slicehost acquisition
– Initially Xen 3.x, but migrated to XenServer
• Next Gen
– Public Launch 8/1/2012
– Powered by OpenStack
• XenServer 6
• Linux, Windows, and FreeBSD VMs
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33. Intro to Cloud Servers
Statistics
• 180,000+ total Rackspace customers (not just Cloud Servers)
• Tens of thousands of hosts
• Hundreds of thousands of VMs
• Millions of snapshots
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35. Why Xen?
• Thin hypervisor layer
• Open source
• Excellent driver support due to Linux dom0
• Good API
• Good performance
• Along with Linux, Windows VMs are a must
– Same virtualization technology desired for Windows
– Microsoft will support
– Good PV driver support
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36. OpenStack
nova-compute w/ XenAPI
• Runs in a utility domU on each host
• Images downloaded in dom0 Physical host running XenServer
– glance XenAPI plugin
• Images attached to nova-compute domU dom0 nova utility domU
– Partitioning changes glance plugin nova-compute
– file-system resizing
• Monitors VMs‟ power_state
agent plugin
• Snapshots/backups xenstore plugin nova instance
• VM resize/migration domUs
– rsync to new host
• Communicates w/ agent inside VMs
– Via xenstore
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38. OpenStack Rackspace Specifics
Source Code
• Rackspace tracks trunk
– Deployed code generally less than 2 weeks behind trunk
• Some custom patches on top of trunk
– Features specific to Rackspace
– Custom scheduling to meet Rackspace needs
– Scaling with OpenStack Compute Cells
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39. Deploying OpenStack
„Inception‟
• Private internal cloud
– Based on Openstack, called iNova
– OpenStack services for public cloud run virtualized under iNova
• Easy to spin up additional services for load balancing
– Enables quick reaction to load spikes
• Easier deployments of new compute cells
• Automated reaction to downed hosts
• Enables new strategies for deployments
– Replace vs Upgrade
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40. Deploying OpenStack
iNova Diagram
iNova
OpenStack Control
Public Cloud
Infrastructure for
XenServer hosts
Public Cloud
XenServer hosts
domUs
XenServer host w/
OpenStack Control
Public Cloud
Infrastructure for iNova XenServer hosts
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41. Deploying OpenStack
Continuous Deployment
• Trunk and custom branches merged multiple times daily
– Unit Tested and Packaged
• Configuration managed with puppet
– Follows same QE and Continuous Deployment rules as code
• QE Environment
– OpenStack control infrastructure deployed on iNova
– nova-compute upgraded on 200 hosts
– Smoke tests
• Staging Deploy
– Uses the same packages and puppet manifests
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http://docs.openstack.org/essex/openstack-compute/admin/content/logical-architecture.htmlAPI + Dashboard: How you access the systemIdentity: Account managementSwift:storage distributed across multiple disksMassive rsync loopNote:Volume and Network being pulled out as separate components
Lets look at how an image is launched in OpenStack
Been using Xen since before KVM was an option.
Rackspace specific features mostly means features the community doesn’t care about or features that are just not appropriate for the community.