Citrix Systems 6 User Manual

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Document Overview
This document is a system administrator's guide for Citrix XenServer
®, the complete server virtualization platform
from Citrix
®. It contains procedures to guide you through configuring a XenServer deployment. In particular, it
focuses on setting up storage, networking and resource pools, and how to administer XenServer hosts using the
xe command line interface.
This document covers the following topics:
• Managing users with Active Directory and Role Based Access Controls
• Creating resource pools and setting up High Availability
• Configuring and managing storage repositories
• Configuring virtual machine memory using Dynamic Memory Control
• Setting control domain memory on a XenServer host
• Configuring networking
• Recovering virtual machines using Disaster Recovery and backing up data
• Monitoring and managing XenServer
• Troubleshooting XenServer
• Using the XenServer xe command line interface
Introducing XenServer
Citrix XenServer
® is the complete server virtualization platform from Citrix®. The XenServer package contains
all you need to create and manage a deployment of virtual x86 computers running on Xen
®, the open-source
paravirtualizing hypervisor with near-native performance. XenServer is optimized for both Windows and Linux
virtual servers.
XenServer runs directly on server hardware without requiring an underlying operating system, which results in
an efficient and scalable system. XenServer works by abstracting elements from the physical machine (such as
hard drives, resources and ports) and allocating them to the virtual machines running on it.
A virtual machine (VM) is a computer composed entirely of software that can run its own operating system and
applications as if it were a physical computer. A VM behaves exactly like a physical computer and contains its own
virtual (software-based) CPU, RAM, hard disk and network interface card (NIC).
XenServer lets you create VMs, take VM disk snapshots and manage VM workloads. For a comprehensive list of
major XenServer features and editions, visit 
.
Benefits of Using XenServer
Using XenServer reduces costs by:
• Consolidating multiple VMs onto physical servers
• Reducing the number of separate disk images that need to be managed
• Allowing for easy integration with existing networking and storage infrastructures
Using XenServer increases flexibility by:
• Allowing  you  to  schedule  zero  downtime  maintenance  by  using  XenMotion  to  live  migrate  VMs  between
XenServer hosts
• Increasing  availability  of  VMs  by  using  High  Availability  to  configure  policies  that  restart  VMs  on  another
XenServer host if one fails