PCI, SCSI, and Fibre Channel

The PCI standard had its origins in the PC world, and has supplanted the two earlier standard microprocessor backplane buses�VME and Multibus. VME is, however, still used in real-time systems and in some process control applications. It started as a 16-bit bus and later grew to 32 bits; for the most part, VME-based systems used Motorola 68000-family microprocessors.

Multibus I was also a 16-bit bus initially, but Multibus systems tended to house Intel processors. While Intel extended the definition of Multibus I to 32 bits as Multibus II, the new version never saw wide adoption and disappeared fairly quickly.

We can summarize PCI�s major characteristics as follows:

� Two data transfer widths�32 bits and 64-bits

� Two clock rates�33MHz and 66MHz

� Various available bandwidths (133, 266, and 532 MB/sec), depending on clock rate and data width, and with burst-mode transfers

� The ability to support both 32 and 64 controllers on the same bus

� The ability to automatically discover the configuration of devices on the bus at system initialization (known as Plug and Play; this avoids tedious parameter setting in control tables)

� The ability to plug in and remove controllers without stopping the system, a capability known as hot plug.

PCI offers�even in its slowest version�substantially higher throughput than the earlier buses (and higher than MCA and EISA, too, which offered 33MB/sec and 40MB/sec respectively).

The significantly greater demands of more recent technologies, such as Gigabit Ethernet or Fibre Channel, have led to a proposal for a first extension to PCI, called PCI-X, with 32- or 64-bit data widths running at 66, 100 or 133MHz. The bandwidth of a 64-bit, 133MHz PCI-X interface is 1064MB/sec. Along with the physical enhancements, the bus protocol has also been improved in order to enhance efficiency.

The capabilities have been further extended into PCI-X 2.0, whose specifications were approved early in 2002. The goals of PCI-X 2.0 may be summarized as:

� Meet performance needs with an interface capable of handling 64-bit data widths running at 266 or 533MHz and with a throughput of 2128 or 4256 MB/sec respectively

� Support the use of earlier-generation cards to protect earlier investments (of course, this simply means that old cards must work with the new bus; a PCI-X 2.0 system with a mix of cards meeting earlier specifications and cards meeting 2.0 specifications will run at the speed of the slowest card)

� Become an industry standard

� Integrate well with the InfiniBand initiative (see below)

These various buses all represent the classical way to connect up peripherals and controllers �New I/O Structures: InfiniBand�we will examine the limitations of the classical approach and show why a new I/O architectural approach is called for.

Source of Information : Elsevier Server Architectures 2005

Understanding 64-Bit Computing

Since it was introduced for Windows operating systems, 64-bit computing has changed substantially. Not only do computers running 64-bit versions of Windows perform better and run faster than their 32-bit counterparts, they are also more scalable because they can process more data per clock cycle, address more memory, and perform numeric calculations faster. Windows 7 supports two different 64-bit architectures:

� x64 This architecture is based on 64-bit extensions to the x86 instruction set, which is implemented in AMD Opteron (AMD64) processors, Intel Xeon processors with 64-bit extension technology, and other processors. This architecture offers native 32-bit processing and 64-bit extension processing, allowing simultaneous 32-bit and 64-bit computing.

� ia64 This architecture is based on the Explicitly Parallel Instruction Computing (EPIC) processor architecture, which is implemented in Intel Itanium (IA64) processors and other processors. This architecture offers native 64-bit processing, allowing 64-bit applications to achieve optimal performance.

Sixty-four-bit computing is designed for performing operations that are memory intensive and that require extensive numeric calculations. With 64-bit processing, applications can load large data sets entirely into physical memory (that is, RAM), which reduces the need to page to disk and increases performance substantially. The EPIC instruction set enables Itanium-based processors to perform up to 20 operations simultaneously.

Currently, the prevalent firmware interfaces are:
� Basic input/output system (BIOS)
� Extensible Firmware Interface (EFI)
� Unified Extensible Firmware Interface (UEFI)

Itanium-based computers differ in many fundamental ways from computers based on the x86 and x64 specifications. While Itanium-based computers use EFI and the GUID partition table (GPT) disk type, computers based on x86 use BIOS and the master boot record (MBR) disk type. Computers based on x64 use UEFI wrapped around BIOS or EFI. This means that there are differences in the way you manage computers with these architectures, particularly when it comes to setup and disk configuration. However, with the increasing acceptance and use of UEFI and the ability of Windows 7 to use both MBR and GPT disks regardless of firmware type, the underlying chip architecture won�t necessarily determine what firmware type and disk type a computer uses. This decision is in the hands of the hardware manufacturer.

Source of Information : Microsoft - Windows 7 Administrators Pocket Consultant 2010

I/O

Neither systems architects nor computer architecture researchers have paid as much attention to I/O as they have to processors. The rationale for this lack of attention is completely unclear to us, since I/O is a key part of a system, being both a driver for system performance and an opportunity for value add�unlike processors, where the economies of scale predominate.

We provided a generic server model with the purpose of identifying the various interconnects of interest, mentioning the interconnects between processor, memory and I/O.

An I/O system comprises a number of elements.

As shown in this diagram, the various elements of a classical I/O subsystem are as follows:

� A system controller implementing the connection between processor(s), memory and the I/O bus(es). In practice, this is often a chip integrating two functions�a memory controller and an I/O controller.

� One or more I/O buses. The industry has converged on the PCI (Peripheral Component Interconnect) bus and its extensions.

� I/O controllers connected to an I/O bus. Peripheral devices�for example, disks directly connected to the system, long-distance network connections (WAN, for Wide Area Network) and local network connections (LAN, for Local Area Network) are connected to these controllers.

� Directly-attached magnetic peripherals (a configuration called DAS, for Directly Attached Storage), on specialized buses such as SCSI, which today is the standard for this purpose.

� Specialized networks are used for the connection of peripheral subsystems, such as disk subsystems (e.g., SAN, for Storage Area Network) or communications subsystems (WAN or LAN). In this domain, the industry is moving to Fibre Channel.

We will first be interested in buses used for I/O (principally PCI and its extensions) and in the connections between controllers and magnetic peripherals (SCSI and Fibre Channel�Arbitrated Loop, or FC-AL) and subsequently in Fibre Channel, used to connect to peripheral subsystems.

Later, we will look at the InfiniBand I/O proposal, which has some chance of gaining traction in the years to come. For this success to come about, widespread industry support will be vital; at the time of writing, we are still waiting for confirmation of such commitment from an appropriate spectrum of industry players. For InfiniBand, we will concentrate on the functionality of I/O interfaces and the optimizations appropriate for communications in a loosely-coupled system, with an emphasis on clusters. Since data is the vital and central element of business information technology, the characteristics of the storage systems used are important factors in the choice of servers. Since data needs to be directly accessible�that is, on-line�permanently, both within a company and outside it (through the Internet), storage systems have become an essential part of a server. Trends in storage subsystems are ever-increasing capacity, performance, and availability, coupled with steadily reducing cost per gigabyte.

Communications support�both local and wide area�also has increasing importance. Reflecting this, specialized subsystems connected to servers have been developed.

Source of Information : Elsevier Server Architectures 2005

Naked Gaming

Good-bye, controller: an Xbox upgrade reads natural gestures

When Nintendo�s Wii game console debuted in November 2006, its motion-sensing handheld �Wiimotes� got players off the couch and onto their feet. Now Microsoft hopes to outdo its competitor by eliminating the controller altogether: this past January it revealed details of Project Natal, which will give Xbox 360 users the ability to manipulate on-screen characters via natural body movement. The machine-learning technology will enable players to kick a digital soccer ball or swat a handball simply by mimicking the motion in their living room.

Microsoft, which announced its ambitious Xbox upgrade plan in June 2009, has not set a release date, but many observers expect to see Natal at the end of the year. It will consist of a depth sensor that uses infrared signals to create a digital 3-D model of a player�s body as it moves, a video camera that can pick up fine details such as facial expressions, and a microphone that can identify and locate individual voices.

Programming a game system to discern the almost limitless combinations of joint positions in the human body is a fearsome computational problem. �Every single motion of the body is an input, so you�d need to program near-infinite reactions to actions,� explains Alex Kipman, Microsoft�s director of innovation for Xbox 360.

Instead of trying to preprogram actions, Microsoft decided to teach its gaming technology to recognize gestures in real time, just like a human does: by extrapolating from experience. Jamie Shotton of Microsoft Research Cambridge in the U.K. devised a machine-learning algorithm for that purpose. It also recognizes poses and renders them in the game space on-screen at 30 frames per second, a rate more than sufficient to convey smooth motion. Essentially, a Natal-enhanced Xbox will capture movement on the fly, without the need for the mirror-studded spandex suit of conventional motion-capture approaches.

Training Natal for the task has required Microsoft to amass a large amount of biometric data. The firm sent observers to homes around the globe, where they videotaped basic motions such as turning a steering wheel or catching a ball, Kipman says. Microsoft researchers later laboriously selected key frames within this footage and marked each joint on each person�s body. Kipman and his team also went into a Hollywood motion-capture studio to gather data on more acrobatic movements.

�During training, we need to provide the algorithm with two things: realistic-looking images that are synthesized and, for each pixel, the corresponding part of the body,� Shotton says. The algorithm processes the data and changes the values of different elements to achieve the best performance.

To keep the amount of data manageable, the team had to figure out which were most relevant for training. For example, the system doesn�t need to recognize the entire mass of a person�s body, but only the spacing of his or her skeletal joints. After whittling down the data to the essential motions, the researchers mapped each unique pose to 12 models representing different ages, genders and body types.

The end result was a huge database consisting of frames of video with people�s joints marked. Twenty percent of the data was used to train the system�s brain to recognize movements. Engineers are keeping the rest in a �ground truth� database used to test Natal�s accuracy. The better the system can recognize gestures, the more fun it will be to play the game.

Of course, Microsoft is not the only company exploring gestural interfaces. Last May, Sony demonstrated a prototype unit that relies on stereo video cameras and depth sensors that, it says, could be used to control a computer cursor, game avatar or even a robot. Canesta, a company that makes computer-vision hardware, has demonstrated a system that lets couch potatoes control the TV with a wave of the hand and has partnered with computer manufacturers Hitachi and GestureTek to create gestural controls for PC applications.

Still, the controller should not disappear altogether, says Hiroshi Ishii, who is head of the Tangible Media Group at the M.I.T. Media Laboratory. �I�m a strong believer in having something tangible in your hand,� he says. Wiimote devices, moreover, provide haptic feedback, such as vibration or resistance, which makes the action more realistic. Even for activities like Natal�s soccerlike Ricochet game demo, Ishii points out, a player might miss the feeling of connecting with a physical object that a controller provides.

But Peter Molyneux, creative director of Microsoft Game Studios Europe, looks forward to a new breed of computer entertainment, because eliminating game controllers opens up more creative possibilities. �Natal is forcing me as a designer to think of this as a relationship between the player and a piece of technology,� he says. �We�re trying to make something that feels as if it�s alive.�

Source of Information :  Scientific American Magazine February 2010

Fedora 12 Enabling Authentication

In most situations, you will enable shadow passwords and SHA512 passwords (as selected by default) to authenticate users who log in to your computer from local passwd and shadow password files. To change that behavior, you can select the Use Network Login button during the Create User setup during Firstboot.

The shadow password file prevents access to encrypted passwords. SHA512 is an algorithm used to encrypt passwords in Linux and other UNIX systems. It replaces an algorithm called crypt, which was used with early UNIX systems. When you enable SHA512 passwords, your users can have longer passwords that are harder to break than those encrypted with crypt. You can also use MD5 or SHA256 for encrypting passwords, although these methods are less secure.

If you are on a network that supports one of several different forms of network-wide authentication, you may choose one of the following features (on the Authentication tab):

� Enable Kerberos Support � Tick this check box to enable network authentication services available through Kerberos. After enabling Kerberos, you can add information about a Kerberos Realm (a group of Kerberos servers and clients), KDC (a computer that issues Kerberos tickets), and Admin server (a server running the Kerberos kadmind daemon).

� Enable LDAP Support � If your organization gathers information about users, you can tick this check box to search for authentication information in an LDAP server. You can enter the LDAP Server name and optionally an LDAP distinguished name to look up the user information your system needs.

� Enable Smart Card Support � Tick this check box to allow users to log in using a certificate and key associated with a smart card.

� Fingerprint Reader � Tick this check box to allow users to authenticate using a fingerprint reader.

� Enable Winbind Support � Tick this check box to configure your computer to authenticate users from information retrieved from NTDOM or ADS servers.


In addition to the services just mentioned, you can also select from various ways of gathering distributed user information, if any of these methods are supported on your network.

� Configure Hesiod � If your organization uses Hesiod for holding user and group information in DNS, you can add the LHS (domain prefix) and RHS (Hesiod default domain) to use for doing Hesiod queries.

� Configure NIS � Select this button and type the NIS domain name and NIS server location if your network is configured to use the Network Information System (NIS). Instead of selecting an NIS Server, you can select the check box to broadcast to find the server on your network.

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux

Fedora 12 Choosing Different Install Modes

Although most computers automatically install Fedora in the default mode (graphical), there may be times when your video card does not support that mode. Also, although the install process will detect most computer hardware, there may be times when your hard disk, Ethernet card, or other critical piece of hardware cannot be detected and you�ll need to enter special information at boot time.

The following is a list of different installation options you can use to start the Fedora install process. You would typically try these modes only if the default mode failed (that is, if the screen was garbled or installation failed at some point). For a list of other supported modes, refer to the /usr/share/doc/anaconda*/command-line.txt file (if you have a running Fedora system somewhere with the anaconda package installed) or press F1 through F5 keys to see short descriptions of some of these types.

To use these boot options, highlight the first entry on the boot menu and press Tab. When the boot command appears at the bottom of the screen, type the options you want at the end of that line and press Enter to boot the install process.

� text: Type text to run installation in a text-based mode. Do this if installation doesn�t seem to recognize your graphics card. The installation screens aren�t as pretty, but they work just as well.

� ks: Type ks to run a Fedora installation using a kickstart file. A kickstart file provides some or all of the installation option answers you would otherwise have to select manually.

� lowres: Type lowres to run installation in 640 x 480 screen resolution for graphics cards that can�t support the higher resolution. To choose a particular resolution, use the resolution option. For example: resolution=1024x768.

� noprobe: Typically, the installation process will try to determine what hardware you have on your computer. In noprobe mode, installation will not probe to determine your hardware; you will be asked to load any special drivers that might be needed to install it.

� mediacheck: Type mediacheck to check your DVD before installing. Because media checking is done next in the normal installation process, you should do this only to test the media on a computer you are not installing on. For Fedora Live CDs, select the Verify and Boot option to check the CD before booting.

� rescue: The rescue mode is not really an installation mode. This mode boots from DVD or CD, mounts your hard disk, and lets you access useful utilities to correct problems preventing your Linux system from operating properly.

� vnc vncconnect=hostname vncpassword=******: Run the install in VNC mode to step through the installation process from another system.

� dd: Type dd if you have a driver disk you want to use to install.

� askmethod: Type askmethod to have the installation process ask where to install from (local DVD/CD, NFS image, FTP, HTTP, or hard disk).

� nocddma: Type nocddma to turn off DMA. Errors with some CD drives can be overcome by turning off the DMA feature. This is a good option to try if an install CD or DVD you know to be good fails media check. You could also try ide=nodma to turn of DMA for all IDE devices.

� updates: Type updates to install from an update disk.

You can add other options to the linux boot command to identify particular hardware that is not being detected properly. For example, to specify the number of cylinders, heads, and sectors for your hard disk (if you believe the boot process is not detecting these values properly), you could pass the information to the kernel as follows: linux hdx=720,32,64. In this example, the kernel is told that the hard disk hdx has 720 cylinders, 32 heads, and 64 sectors. You can find this information in the documentation that comes with your hard disk (or stamped on the hard disk itself on a sticker near the serial number).

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux

Choosing computer hardware to Install Fedora 12

This may not really be a choice. You may just have an old PC lying around that you want to try Fedora on. Or you may have a killer workstation with some extra disk space and want to try out Fedora on a separate partition or whole disk. To install the 32-bit PC version of Fedora successfully (that is, the version on the accompanying DVD), the computer must have the following:

� x86 processor � Your computer needs an Intel-compatible CPU. With the latest version, Fedora recommends that you at least have a Pentium-class processor to run Fedora. For a text-only installation, a 200 MHz Pentium is the minimum, while a 400 MHz Pentium II is the minimum for a GUI installation.

� DVD or CD-ROM drive � You need to be able to boot up the installation process from a DVD, CD-ROM, or other bootable drive. (You can also boot from a USB flash memory drive by using the livecd-tools package to build an installable image for your USB device from the live CD or another minimal boot image.) Once you have booted from one of the media just described, you can use the Internet or a LAN connection to install Fedora software packages from a server on the network, or you can figure out a way to copy the contents of the DVD to a local hard disk to install from there.

� Hard disk � The minimum amount of space you need varies depending on the installation type and packages you select. If you are an inexperienced user, you want at least 2.3GB of space so you can get the GUI (with some Office and Productivity apps) or 3GB if you want to do software development. Although different install types are no longer supported in Fedora, the following items roughly indicate how much disk space you need to install different types of desktop or server systems:
� Office and Productivity � Requires 2.3GB of disk space.
� Software Development � Requires 3.0GB of disk space.
� Web Server � Requires 1.1GB of disk space.
� Minimal � Requires at least 620MB of disk space.

� RAM � You should have at least 128MB of RAM to install Fedora (text mode only). If you are running in graphical mode, you will want at least 192MB. The recommended minimum RAM (for decent performance) for GUI mode is at least 256MB.

� Keyboard and monitor � Although this seems obvious, the truth is that you need only a keyboard and monitor during installation. You can operate Fedora quite well over a
LAN using either a shell interface from a network login or an X terminal. For the really advanced, it is even possible to do a graphical network install over VNC (virtual network computing), a serial console, or an integrated lights out (ILO) solution to do a headless install.

Fedora versions, are available for the AMD64 architecture and PowerPC. The minimum PowerPC hardware supported is a PowerPC G3/POWER3.
Supported PowerPC products include the Apple Power Macintosh (1999 or later), IBM 32-bit RS/6000, Genesi Pegasos II, as well as 64-bit G5 and POWER processors from IBM eServer pSeries computers. Check the Fedora Project download site for information on PPC versions of Fedora.

For other hardware, such as Intel Itanium and IBM mainframe, there are versions of Red Hat Enterprise Linux available (which you have to purchase from Red Hat, Inc.).

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux

Install Fedora 12 From DVD, network, or hard disk?

When you install Fedora, the distribution doesn�t have to come from the installation DVD or CD. After booting the installation DVD, press Tab with the Install selection highlighted. Then type the word askmethod at the end of the boot command line displayed and press Enter. You are offered the choice of installing Fedora from the following locations:

� Local DVD or CDROM � This is the most common method of installing Fedora and the one you get by simply pressing Enter from the installation boot prompt.

� Hard drive � If you can place a copy of the Fedora distribution on your hard drive, you can install it from there. (Presumably, the distribution is on a hard drive partition to which you are not installing.)

� NFS directory � Allows you to install from any shared directory on another computer on your network using the Network File System (NFS) facility.

� HTTP� Lets you install from a Web page address (http://) or FTP site (ftp://).

If your computer doesn�t have a DVD drive, you can use the boot.iso CD image from http://download.fedoraproject.org/. Navigate to releases/12/Fedora/i386/os/images/ to get the boot.iso CD image file. Make a CD from this file and use that CD to start a network install (HTTP, FTP, or NFS). Just type linux askmethod at the boot prompt to begin the installation process.

If you don�t have a bootable DVD or CD drive, there are other ways to start the Fedora installation. Unlike some earlier Fedora and Red Hat Linux versions, Fedora doesn�t support floppy disk boot images (the Linux kernel is too large to fit on a floppy disk). Therefore, if you don�t have a bootable DVD or CD drive, you need to start the install process from some other medium (such as a USB device, PXE server, or hard drive).

The following specialty installation types also may be of interest to you:

� Boot CD � You can create a boot CD from the location mentioned above. Copy and burn the file boot.iso from the images directory. You can use the CD you create from that image to begin the install process if you have a DVD drive that is not bootable or if you have the Fedora 12 software available on any of the media described in the linux askmethod section.

� USB or other bootable media � If your computer can be configured to boot from alternate bootable media, such as a USB pen drive, that is larger than a floppy disk, you can use the livecd-tools package to build an installable image for your USB device from one of the Live CD or minimal boot images.

� Kickstart installation � Lets you create a set of answers to the questions Fedora asks you during installation. This can be a time-saving method if you are installing Fedora on many computers with similar configurations.

A Fedora Installation Guide is now available from the Fedora Project if you find you need further information. You can access the guide here:

http://docs.fedoraproject.org/install-guide/f12/en-US/html-single/

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux

Fedora 12 selecting Install or upgrade?

First you should determine if you are doing a new install or an upgrade. If you are upgrading an existing Fedora system to the latest version, the installation process will try to leave your data files and configuration files intact as much as possible. You also need to do the upgrade from the DVD because upgrades are not available from the Fedora live CD.

An upgrade installation takes longer than a new install. A new install will simply erase all data on the Linux partitions (or entire hard disk) that you choose. (You can optionally select which partitions to format.)

If you choose to upgrade, you can save yourself some time (and disk space) by removing software packages you don�t need. An upgrade will just skip packages that are not installed and not try to upgrade them. Here are a few other tips related to upgrades:

� Conflicting packages � If you upgrade a system on which you installed packages from sources outside of the Fedora project that conflict with Fedora packages, those features may no longer work. For example, if you replaced GNOME with Ximian GNOME or used a third-party KDE package set, you can�t upgrade those packages to Fedora 12 (It�s probably best to remove those packages before upgrading, and then apply them again later if you like.)

� Third-party packages � If you have installed packages from third-party repositories that are specific to your current kernel (such as drivers for NVidia video cards or wireless LAN cards) you will need to get new versions of those packages that match your upgraded kernel.

� Kernel requirements � To upgrade, you must have at least a Linux 2.0 kernel installed on the system you are upgrading.

� Configuration files � With an upgrade, your configuration files that are replaced are saved as filename.rpmsave (for example, the hosts file is saved as hosts.rpmsave). More often, however, your old configuration files will remain in place, while the system copies new configuration files to filename.rpmnew. The locations of those files, as well as other upgrade information, is written to /root/upgrade.log. The upgrade installs the new kernel, any changed software packages, and any packages that the installed packages depend on being there. Your data files and configuration information should remain intact.

� Digital certificates � If you are using digital certificates on your system, you must relocate them to the /etc/pki directory after the upgrade.

� Java � If you used the Java RPM from Sun Microsystems to provide Java support, conflicts with that package may cause it to be erased during an upgrade. If that occurs, you can install the Java RPM from jpackage.org or install the Java tarball from Sun Microsystems into your /opt directory. You can also consider removing that version of
Java from your system and instead using the open source Java IcedTea packages included with Fedora to provide Java support.


A feature that is available when you are upgrading to Fedora 12 is the preupgrade package. By installing preupgrade on a Fedora 11 system (yum install preupgrade), you can prepare your system to upgrade to Fedora 12 by launching a single application to:

� Determine which packages need to be downloaded to upgrade to Fedora 12.

� Download the packages needed to complete the upgrade (while Fedora 11 is still running)

� Download the boot images needed for the upgrade.

The advantage to using preupgrade is that you can continue using your system while you do most of the time-consuming work (such as downloading packages) that needs to be done to complete an upgrade. Also, before you get into running the installer, you will be able to see if there are any package dependencies you should deal with (before committing to the actual upgrade).

With the preupgrade package installed, you can start the GUI version of preupgrade by typing preupgrade from a Terminal window as root user. Files needed for the upgrade are copied to the /var/cache/yum/preupgrade* directories. Once preupgrade is complete, you can reboot to begin the upgrade.

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux

Fedora 12 Quick Installation

If you have a little bit of experience with computers and a computer with common hardware, you can probably install Fedora pretty easily. The procedure in this section will get you going quickly if you have:

� Media � The Fedora installation DVD or live/install CD

� PC � A Pentium-class PC (at least 200 MHz for text mode; 400 MHz Pentium II for GUI) with a built-in, bootable DVD or CD drive, at least 128MB of RAM (for text mode) or 256MB of RAM (for GUI mode).

� Disk space � If you are installing from the live CD, you need at least 3GB of disk space. Keep in mind that the live CD install only copies the live CD files to your hard disk. You don�t get to select individual packages, as you do when installing from the DVD. (The fact that files are compressed on the CD accounts for the need for more hard disk space than the 700MB CD image would indicate.)

With the DVD, depending on which packages you choose to install, the disk space you need can range from about 600MB (for a minimal server with no GUI install) to 10GB (to install all packages). I recommend from 2GB to 3GB minimum if you are installing a desktop system. (The Fedora Project recommends at least 5 percent of additional free space, plus any disk space you require for user data.)

For this quick procedure, you must either be dedicating your entire hard disk to Linux, have a preconfigured Linux partition, or have sufficient free space on your hard disk outside any existing Windows partition.

Here�s how you get started:
1. Insert the Fedora 12 installation DVD or live CD into your computer�s drive.

2. Reboot your computer.

3. The next step depends on whether you are using the live CD or DVD

� For the DVD, choose whether you want to install or upgrade an existing system.

� For the install/live CD, let the boot screen time out. When the CD boots up to a GNOME desktop, double-click the Install to Hard Drive icon to begin the installation.

During installation, you are asked questions about your computer hardware and the network connections. After you have completed each answer, click Next. The following list describes the information you will need to enter.

� Install or Upgrade � If you are installing from DVD and have an earlier version of Fedora installed, you can choose Upgrade to upgrade your system without losing data files. Otherwise, you can continue with a new installation by selecting Install Fedora.
(Upgrades are not supported when you are installing from the live CD.)

� Media Check � If you are installing from the DVD, you can optionally check the DVD to be sure it is not damaged or corrupted. This choice is not on the live CD.

� Language Selection � Choose the language used during the install (you can add other languages later). This choice is not on the live CD.

� Keyboard Configuration � Choose your keyboard type from a list of international keyboard types

� Select Hostname � Choose a hostname for your system.

� Time Zone Selection � Identify the time zone in which you are located. Uncheck the System Clock uses UTC box if you are booting multiple operating systems from this machine because most operating systems expect the BIOS clock to match local time.

� Set Root Password � Add the root user account password.

� Disk Partitioning Setup � Choose to remove Linux partitions, all partitions, or no partitions (and use existing free space) to have space to install Fedora. Because repartitioning can result in lost data.

� Boot Loader Configuration � Add the GRUB boot manager to control the boot process. (GRUB is described later in this chapter.) With multiple operating systems on the computer, select which one to boot by default.

� Choose Software � If you are installing from DVD, choose from several preset installation classes, such as Office and Productivity (for laptop, home, or desktop use), Software Development (desktop plus software development), or Web Server (file, print, Web, and other server software). I suggest you also select Customize now so that you can see exactly which packages you have selected (and add others if you want to). If you are installing from the live CD, you won�t be able to choose the software to install (in this or the next step) because the entire contents of the CD are installed to hard disk.

� Installation Categories � If you are installing from DVD, select each category that appears to see which groups of software packages are installed. Then select the Optional packages button to add or subtract packages from each group.

� Installation � Up to this point, you can quit the install process without having written anything to disk. When you select Next from the installation categories, the selected packages are installed.

When installation is done, remove the Fedora DVD and click Exit to reboot your computer. If you installed from the live CD, reboot your computer and remove the live CD before it�s time for the installed system to boot. Linux should boot by default. After Linux boots for the first time, Firstboot runs to let you read the license information, set the system date and time, add a user account, and optionally, send the Fedora Project details of your system hardware. On subsequent reboots, you will see a login prompt. You can log in and begin using your Linux system.

NOTE: After answering the questions, the actual installation of packages from the DVD takes between 20 and 60 minutes, depending on the number of packages and the speed of the computer hardware. For the live CD, the installation process is typically much faster because the contents of the CD are simply copied to hard disk. Upgrades can take much longer.

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux

One Small Step for Intellectual Property

One Small Step for Intellectual Property, One Giant Leap Backwards for The Cloud

n the past weeks, many people will already have read many stories centreing on the Megaupload take-down and the continuing war for the Internet. Most of these stories have no doubt been focused on why the take-down was justified or why it was unfair to users who were using the service for legitimate purposes. Many users lost much when Megaupload was shut down, but more important is the drastic effect this will have on the future of Cloud computing.

So what is The Cloud?

The Cloud is a term being used more and more in computing circles. While there are many definitions, a simplistic view of The Cloud as a place in cyberspace where some computing service takes place is good enough. Many companies exist solely in The Cloud, such as Amazon, and many more use the web platform to provide goods, or even services - such as Google Docs - to millions of users world-wide. So The Cloud is important and is being used more and more as it becomes more reliable.

Reliability and Ubiquity

Regardless of your opinion of the site itself, many of its users were legitimate. Some artists used Megaupload exclusively to distribute their music; it was a very useful platform for making files available via the Internet. The Internet is so ubiquitous these days that it is not unreasonable to place your files in a digital locker such as Megaupload and expect that wherever you go, you can still get at your data. This is taken even further with services like Google Docs, where not only are the files available on-line but they are authored there as well.

Google protects against losing their customers' data by replicating it to several geographically remote locations. Many companies use the Amazon web services; reliability is a key concern here as well. If companies are to trust their business to run on Amazon's servers, will their data be safe? With replication and virtualisation, the answer is probably yes. If businesses are to trust The Cloud, they need to know that their data will be safe there. This is the digital age where almost everything is done on-line, whether it is ordering more stock or reporting sales figures, and in these modern times many companies will suffer heavily if they lose access to the Internet. However, because many processes have offline fall-backs, this is not a complete disaster - in most cases, business can still carry on uninterrupted, although far more inefficiently. It would be a far different issue if the data needed for everyday business was kept on-line as well; what good is knowing that the data is safe if you can't access it?

Disasters, Thin-clients and Internet Dependence

So with Google, Amazon and other similar companies offering to keep your data for you with such a high level of security, it has actually become more likely for local hardware failure to be the cause of data loss. If one of Google's hard drives dies, the data is simply re-replicated elsewhere. However, for companies who have kept away from The Cloud, a flood, fire, break-in or even just some old hardware reaching the end of its life is likely to result in many problems and probably some data loss. Even a system like RAID, which is supposed to keep your data replicated, is not infallible, especially in the case of a natural disaster. As companies experience these losses, the experience may lead them to consider putting their data on-line. Due to the complexity inherent in keeping an on-line system synchronised with an offline one, many of the companies going down this route are choosing to put all their eggs in the Cloud basket.

Not so long ago, a new computer would have cost hundreds of thousands of dollars. That age has long since gone; in the modern world, information is far more valuable than hardware. For large companies, if a computer fails it is not worth the time and money to fix and it is often cheaper just to buy a new machine to allow work to resume as soon as possible. To this end, many schools and businesses are choosing to use thin-clients, which have little processing power of their own, and use remote servers to do all the work. It has been proposed that in the future no individuals and few businesses will own physical hard drives; most people will just have a simple terminal to access a web platform with all the functionality in a modern computer is all that is needed and with the recent advancements in system-on-chip devices this seems all the more likely. Why bother with the expense and risk of hosting everything yourself, if Google, and those like them, can do it so much better than you ever could, for free? Even schoolchildren forgetting to bring in their homework could be a thing of the past with systems like Google Docs - that is, providing the Internet is reliable enough.

What the Megaupload take-down means for The Cloud

More companies are choosing to use The Cloud every day and leaving the hardware worries, backups and upgrades to Cloud services. For the last few years the world has been looking towards Cloud computing as the future, but the take-down of Megaupload with no prior warning has taken The Cloud back from the precipice of success and threatens this kind of advanced usage.

The Megaupload take-down proved that, with no prior warning, a Cloud service can be taken offline due to its misuse by other users. What does this say for other services? Will Google be the next victim because it indexes sites which may contain illegal content and because it owns YouTube, which contains infringing videos? What will Amazon's users do if they are taken down with no warning because some users were running bootleg movies, drugs or even child pornography through the same service? Is it fair to remove the entire service, punishing the legitimate users as if they were criminals? In the case of Megaupload, not only was the service taken offline but the go-ahead was given to erase all the data without allowing legitimate users to claim back their data. For a business, losing all their sales information with no warning would cause havoc if they ever got audited. Indeed, this precedent could be used to close down a bank because some of its clients were criminals. Should we all be left without a service because some choose to abuse it?

Conclusion

The take-down of Megaupload is a dangerous warning of the power that law enforcement agencies have, and it proves that the greatest asset of The Cloud - its reliability - is no longer unquestionable. The trust that people had in The Cloud has been damaged severely, and it will take many years of hard work to win back. If the FBI or other similar institutions can take down a service because a sub-set of the user base is abusing it, then the chances of something as ubiquitous as Google being here tomorrow become no more certain than the flip of a coin.

If you can't explain something simply, you don't know enough about it. (Albert Einstein)

                       

                                                                                  

                                                                                  

Using the Fedora 12 Live CD

The official Fedora 12 Desktop Live CD is a great way to try out Fedora before you commit to installing it. In addition to answering the obvious question of �does Fedora run on my PC at all?� the CD itself contains useful tools for examining your hardware and preparing your computer for installation.

USB flash drives can be used the same way) that contains an entire operating system. In most cases, you can boot the live CD without touching the contents of your hard drive. With the Fedora 12 Desktop Live CD, you can boot up to a working GNOME desktop that works like most desktop computer systems installed to hard disk. If you don�t like the system, then reboot, remove the CD, and your computer will return to the way it was. If you like it, you can click a single button and install the same desktop system to your hard disk.

Here�s a quick set of steps to try out the Fedora 12 Desktop Live CD (included with this book):

1. Insert the Fedora 12 Desktop Live CD into your CD drive and reboot.

2. From the boot screen, either let the CD timeout and boot or press any key to see other selections. From the boot menu, highlight either Boot or Verify and Boot, and then press Enter. (The verify step makes sure the medium isn�t corrupted.)

3. When you see the login screen, you can select a language or just let the login prompt timeout. (No password is required because this is a live CD.) The GNOME desktop starts up.

4. From the GNOME desktop, here are a few things you can try from the live CD:

� Run applications � Try any of the applications you choose from menus in the top panel. If you have an Internet connection (Fedora will automatically configure most wired Ethernet cards), you can try Web browsing and other Internet applications. You can even add more applications. Select System -> Administration -> Add/Remove Software to select applications to install over the Internet. (Because the live CD is a read-only medium, software you add will disappear when you reboot.)

� Check hardware

� Prepare for dual booting � If you want to keep an installed Windows system that is already on your computer�s hard disk, you can prepare your computer to be able to dual boot both Windows and a new install of Fedora.


If you like the live CD, and your computer is prepared for you to install to it, you can immediately install the contents of the live CD to your computer�s hard drive. Select the Install to Hard Drive icon from the desktop, and then follow along the installation procedure in the next sections.


NOTE: The live CD will not run well on less than 256MB of RAM. Also, if you find that the live CD hangs at some point in the boot process. With the boot label highlighted on the boot menu, press the Tab key to be able to add boot options to the boot command. Keep in mind that the performance of a CD is not comparable to that of a hard disk. Once you have installed Fedora on your hard disk it should be much faster and more responsive.


NOTE: If you prefer the KDE Desktop Environment over GNOME, Fedora offers a live CD spin based on the KDE desktop. You can download that live CD from any Fedora mirror site.

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux

Understanding Fedora Installation Media

The Fedora project includes a lot of software to help you get started installing the release as well as creating your own releases, if you desire. These include:

� Fedora Repository � This repository, maintained by the Fedora Project, includes all the software.

� Installation Media � The Fedora repository contains too much software to expect the average person to download. Therefore the Fedora Project offers more reasonable-sized installation media that include a single 3.5G installation DVD, a GNOME Desktop Live CD, and a KDE Desktop Live CD. Either of the live CDs can also be used to install the Fedora desktop system contained on that CD to hard drive. You can also download the equivalent of the installation DVD as a set of five CDs if you don�t have a writable DVD drive. See http://fedoraproject.org/en/get-fedora-all to download Fedora.

� Spins � After the release, look for Fedora spins that include custom releases of Fedora, typically aimed toward special interests such as games, education, or electronic design (http://spins.fedoraproject.org/). A spin is just a selected grouping of Fedora software into a live or install CD or DVD image. Other spins include special desktop integration such as the Xfce desktop spin.

� Build Tools � To help people put together the mass of Fedora software into a form that is useful to them, the Fedora Project created several software tool projects. With Fedora and optionally other software repositories, Pungi can be used to create a new set of
installation media, while livecd-creator can build a live CD or live DVD.

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux

The Culture of Free Software

Fedora was born from a culture of free software development and continues to thrive from that culture. The copyright for software included in Fedora systems is covered primarily under the GNU public license. That license, which most free software falls under, provides the following:

� Author rights � The original author retains the rights to his or her software.

� Free distribution � People can use the GNU software in their own software, changing and redistributing it as they please. They do, however, have to include the source code with their distribution (or make it easily available).

� Copyright maintained � Even if you were to repackage and resell the software, the original GNU agreement must be maintained with the software. This means that all future recipients of the software must have the opportunity to change the source code, just as you did.

It is important to remember that there is no warranty on GNU software. If something goes wrong, the original developer of the software has no obligation to fix the problem. However, the Linux culture has provided resources for that event. Experts on the Internet can help you iron out your problems, or you can access one of the many Linux newsgroups or forums to read how others have dealt with their problems and to post your own questions about how to fix yours. Chances are that someone will know what to do � and may even provide the software or configuration file you need.

If you need reliable support for your Linux system, commercial Linux support is available from a variety of companies. Also, many of the software projects that go into Linux offer their own support features, which lets you get help directly from those who are building the code.

NOTE: The GNU project uses the term free software to describe the software that is covered by the GNU license. Many Linux proponents tend to use the term open source software to describe software. Although source code availability is part of the GNU license, the GNU project claims that software defined as open source is not the same as free software because it can encompass semi-free programs and even some proprietary programs. See http://www.opensource.org for a description of open-source software.

Source of Information :  Wiley - Adobe Fedora Bible 2010 Edition Featuring Fedora Linux