Installation and Configuration
By High School Technology Services myhsts.org Recap From Previous Session
● UNIX, Linux and Open Source ● Duties of the System Administrator ● Superusers and the Root Login ● Sharing Superuser Privileges with Others (su and sudo Commands) ● TCP/IP Networking Fundamentals Planning: Hardware and Software Considerations
Linux supports a wide range of PC hardware; but not even Linux supports every known device and system. Your PC must meet certain minimum requirements in order to run Linux. CPU - Linux does not support the Intel 286 and earlier processors. However, it fully supports the Intel 80386, 80486, Pentium, Pentium Pro, Pentium II, and Pentium III processors. Nevertheless, some users feel that their 80386 Linux systems respond sluggishly, particularly when running X. So, if you want optimum performance, you should install Linux on a PC having an 80486 processor or better.
Linux also supports non-Intel processors such as the Cyrix 6x86 and the AMD K5 and K6. Most Linux users have systems that use Intel chips; if your system uses a non-Intel chip, you may find it more difficult to resolve possible problems. Planning: Hardware and Software Considerations
Motherboard - Linux supports the standard ISA, EISA, PCI, and VESA (VLB) system buses used on most IBM-compatible PCs. Linux recently gained support for IBM's MCA bus, used in IBM's PS/2 series of computers. However, at the time of this writing, Debian GNU/Linux does not yet support the MCA bus. If you have an IBM PS/2, you may be unable to install Debian GNU/Linux (check the Debian Project web site for the latest available information on support for the MCA bus).
Your motherboard should include at least 16 MB of RAM for optimum Linux performance. Some users have managed to coax Linux into working on systems with as little as 4 MB of RAM. However, if your system has less than 16 MB of RAM, you probably won't be pleased with its performance. If you plan to run X, you may wish to install more than 16 MB of RAM - perhaps 64 MB. Although X operates well with 16 MB of RAM, you can open more windows and switch between them more quickly if you have additional memory. Planning: Hardware and Software Considerations
Disk - An anonymous wag once quipped that one can never be too thin, too rich, or have too much hard disk space. Fortunately, Linux is not too hungry for disk space. To install and use Linux, you should have at least 250 MB of free hard disk space. (The minimum is about 100 MB, but installing Linux on a system with so little disk space will compel you to omit many useful applications and will leave you with little room to work.) Installation Methods and Types
Following are the installation methods which you can use -
▪ DVD/CD-ROM ▪ Hard Drive ▪ NFS ▪ FTP ▪ HTTP Partitions
Each distribution’s installation guide contains (or should contain) a section on partitioning your hard drive. Personally, I favor the KISS principle (Keep It Simple, Stupid), especially for beginners. If you are installing a server that will serve multiple user’s simultaneously and provide myriad services, you will want to read these manual sections as well as the Partition Mini-HOWTO, an excellent document detailing the reasons one might want to create the seven or more partitions sometimes recommended in these primers. Logical Volume Manager - LVM
LVM is a tool for logical volume management which includes allocating disks, striping, mirroring and resizing logical volumes. With LVM, a hard drive or set of hard drives is allocated to one or more physical volumes. LVM physical volumes can be placed on other block devices which might span two or more disks. The physical volumes are combined into logical volumes, with the exception of the /boot/ partition. The /boot/ partition cannot be on a logical volume group because the boot loader cannot read it. If the root (/) partition is on a logical volume, create a separate /boot/ partition which is not a part of a volume group. Since a physical volume cannot span over multiple drives, to span over more than one drive, create one or more physical volumes per drive. Logical Volume Manager - LVM File System Overview
Ever go looking for a book in the library? In order to find what you’re looking for, you must understand the library’s file system, or method of organization. Fiction books are easy, they use a simple type of file system commonly known as alphabetical by author. Nonfiction books can be tougher because they use a different type of file system, the Dewey Decimal System. What if you don’t understand the Dewey Decimal System? What if you only know the title of a book and you don’t know whether it’s fiction or non-fiction? How can we find our book now? Luckily there is a librarian to help us, and she has created a card catalog (or in most libraries now, a computerized catalog) listing all the books available and where to find them. Now, picture your hard drive as the library. Like the library, your hard drive can have different file systems. The operating system is your librarian, who has provided the directory tree (sometimes also referred to as “the file system”, with a slightly different meaning) as a catalog of the files available. Swap Partition Considerations
You need one partition that will be used as Linux swap space. This is space on your hard drive that can be used as virtual memory. Virtual memory allows your computer to run large programs and perform complex tasks even if it does not have enough physical RAM to do the job. (It is a lot slower, but it works.)
The amount of swap space required is a matter of religious argument among geeks and hackers, and entire volumes could be written about the subject. To keep it simple, create one swap partition that is 50% to 100% the size of the physical RAM in your system. If you are short on RAM with plenty of drive space, go large. If you’re short on drive space and have lots of RAM, go small. Other Partition Considerations
root (/)
The root file system is represented by a forward slash (/). It is the top of the directory tree, and contains Linux and everything that you install with Linux. (See The Linux (Virtual) File System for details). This is roughly equivalent to your “C:” drive under DOS or Windows. You must create a partition for the root directory. Other Partition Considerations
/home
The third and final partition you should create will hold your /home directory. This is the place where all the user-specific files, your data in other words, are stored. It is roughly equivalent to the “My Documents” folder on a MS Windows desktop (if you have MS Office installed). On a multi-user system, each user will have her own directory under /home. The Linux Boot Loader: grub
GNU GRUB (short for GNU GRand Unified Bootloader) is a boot loader package from the GNU Project. GRUB is the reference implementation of the Free Software Foundation's Multiboot Specification, which provides a user the choice to boot one of multiple operating systems installed on a computer or select a specific kernel configuration available on a particular operating system's partitions. Software Package Selection
To specify which packages will be installed, select Software Selection at the Installation Summary screen. The package groups are organized into Base Environments. These environments are pre-defined sets of packages with a specific purpose; for example, the Virtualization Host environment contains a set of software packages needed for running virtual machines on the system. Only one software environment can be selected at installation time. For each environment, there are additional packages available in the form of Add-ons. Add-ons are presented in the right part of the screen and the list of them is refreshed when a new environment is selected. You can select multiple add-ons for your installation environment. Graphics Controllers
As Linux becomes more user-friendly and game developers add Linux support, the biggest question – outside of what physical card to buy – seems to be graphics driver performance. With varying levels of support for each platform, the performance of a graphics card will vary from OS to OS.
Let’s discuss various graphics cards and Linux. Basic Networking Configuration
Before delving into the interface configuration files, let us first itemize the primary configuration files used in network configuration. Understanding the role these files play in setting up the network stack can be helpful when customizing a Red Hat Enterprise Linux system. The primary network configuration files are as follows: /etc/hosts The main purpose of this file is to resolve hostnames that cannot be resolved any other way. It can also be used to resolve hostnames on small networks with no DNS server. Regardless of the type of network the computer is on, this file should contain a line specifying the IP address of the loopback device (127.0.0.1) as localhost.localdomain. For more information, refer to the hosts man page. Basic Networking Configuration
/etc/resolv.conf This file specifies the IP addresses of DNS servers and the search domain. Unless configured to do otherwise, the network initialization scripts populate this file. For more information about this file, refer to the resolv.conf man page. /etc/sysconfig/network This file specifies routing and host information for all network interfaces. /etc/sysconfig/network-scripts/ifcfg-
● Boot Sequence ● The systemd Daemon ● The systemctl Command ● Targets vs. Run Levels ● Modifying a Target ● Service Unit Scripts ● Changing System States ● Booting into Rescue Mode ● Shutdown Commands
Thank You
By High School Technology Services myhsts.org