Virtualization role in IT infrastructure
Server virtualization can help simplify operations, improve utilization and uptime, and enable cost-effective scaling.

Simplifying operations
Server virtualization effectively hides hardware details from software, allowing the hardware to be truly interchangeable without affecting the software. Virtualization can help simplify operations by doing the following:

• Allowing workload portability across multiple servers, which includes the ability to “rehost” software (including legacy operating systems that are no longer supported)
• Streamlining application development and platform certification by certifying on a common virtual interface rather than multiple implementations of physical hardware
• Encapsulating complex configurations into a file that is easily replicated and provisioned

Improving utilization and uptime
Server virtualization can help organizations make optimal use of existing resources. A single physical server with multiple VMs can host several workloads that, without virtualization, would require multiple physical servers. Additionally, because workloads can be relocated or replicated easily in a virtualized environment, administrators can move them when performing maintenance without affecting service levels and can quickly provision new servers as needed. Virtualization can help improve utilization and uptime by doing the following:

What Virtualization Enables

OS virtualization is achieved by inserting a layer of software between the OS and the underlying server hardware. This layer is responsible for allowing multiple OS images (and their running applications) to share the resources of a single server. Each OS believes that it has the resources of the entire machine under its control, but beneath its feet, the virtualization layer, or hypervisor, transparently ensures that resources are properly shared between different OS images and their applications.

What the Xen hypervisor is:

• The industry’s fastest and most secure hypervisor.
• Open source software, collaboratively developed by over 20 of the world’s leading enterprise infrastructure vendors, yet backed by an enterprise quality and service focused vendor, Citrix, which ensures the quality and reliability enterprises demand from their virtualization vendor.
• A common, open industry standard code base that supports all operating systems with high performance and security.

This manual is for system administrators responsible for installing, configuring, deploying, and maintaining the MetaFrame Presentation Server Clients for 32-bit Windows. These clients are available as Program Neighborhood, Program Neighborhood Agent, and the Web Client. This manual assumes knowledge of:

• The server farm to which your Clients connect
• The operating system on the client device (Windows 9x, Windows Me, Windows NT, Windows 2000, Windows XP, or Windows 2003)
• Installation, operation, and maintenance of network and asynchronous communication hardware, including serial ports, modems, and device adapters

This chapter introduces Version 8.x of the Citrix Clients for computers running 32- bit Windows operating systems. It is designed to help you decide which Clients to use in your computing environment and how to deploy them.

Note For information about Clients for other client devices and operating systems, see the documentation included on your MetaFrame Presentation Server Components CD or visit our Web site at http://www.citrix.com/.

What is Ubuntu?

• Server LTS (Long Term Support) launched in June 2006
• Ideal high volume, low cost server deployment
• Supports APT for seamless upgrade (LTS to LTS)
• Quick install profiles – Web, Mail, Database, DNS, LAMP
• Class leading virtualization support

Agenda

How do we differ from Debian? Technology choices

• AppArmor
• KVM
• Upstart
• UFW
• The best guest OS
• Likewise-open

What’s coming?

• Identity Management
• Entreprise Enablement
• Virtualization
• Configuration Backend

The Ubuntu Server Team How to get involved? Package deployment and maintenance Debian Packaging

• Handles package files and configuration
• Allows for tight integration of different packages
• Permit updates of running services
• Tight and documented quality and policies
• Excellent dependency control

The APT (advanced packaging tool) package management system

• One tool for all services and applications

Introduction

The purpose of this guide is to document the installation and configuration of a complete Snort implementation. This guide contains all the necessary information for installing and understanding the architectural layout of the implementation.

The information in this guide was written for implementing Snort 1.8 using Redhat 7.3. You may find some discrepancies if you are installing different versions of Snort or using different versions of Redhat. This guide was written with the assumption that you understand how to run Snort and have a basic understanding of Linux. This includes editing files, making directories, compiling software and understanding general Unix commands. This guide does not explain how to use or configure Snort, but information on where to obtain this information can be found in the “Additional Information” section.

Required Software