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Week Nine Agenda • Announcements Final exam will be longer, and more specific • Document your text files (4 th_log. txt, startup. txt) • Link of the week • Review week eighth lab assignment • Week nine expected outcomes • Next lab assignment • Break-out problems • Upcoming deadlines • Lab assistance, questions, and answers
Link of the week http: //en. wikipedia. org/wiki/Firmware This Web site contains information on: - Evolved firmware uses - Firmware and device drivers - Firmware support challenges in PCs - Firmware hacking http: //www. driver-fix. com/driverdetective. php? t=Firmware Diver. Detective Download driver updates automatically and safely. This software utility will keep your system up-to-date by automatically retrieving the latest drivers from your hardware’s manufacturer.
Link of the week Define Firmware: A computer program that is embedded in the hardware device. Firmware can be stored in flash memory or as a binary image file that can be uploaded onto existing hardware by a user. In summary, firmware is a combination of hardware and software. Firmware applications include the following: - BIOS found in IBM-compatible PCs. - Open Firmware, used in computers marketed by Sun Microsystems and Apple Computers. - Computer peripherals - The i. Pod’s control menus. - Automobiles employed on-board computer and various sensors. - Cisco IOS
Review eighth week lab assignment American National Standards Institute (ANSI) • ANSI The Institute oversees the creation, promulgation and use of thousands of norms and guidelines that directly impact businesses in nearly every sector: from acoustical devices to construction equipment, from dairy and livestock production to energy distribution, and many more. ANSI is also actively engaged in accrediting programs that assess conformance to standards – including globally-recognized cross-sector programs such as the ISO 9000 and ISO 9001. • Membership: Comprised of Government agencies, Organizations, Companies, Academic and International bodies, and individuals, the American National Standards Institute (ANSI) represents the interests of more than 125, 000 companies and 3. 5 million professionals.
Review eighth week lab assignment • ANSI is the official U. S. representative to the International Organization for Standardization (ISO). • The American National Standards Institute has served in its capacity as administrator and coordinator of the United States private sector voluntary standardization system for more than 90 years.
Review eighth week lab assignment Linux /etc/sysconfig The /etc/sysconfig directory contains files that control the system configuration. /etc/sysconfig/clock Used to configure the system clock to Universal Time and other clock parameters. /etc/sysconfig/init This file controls how the system will appear and function during the boot process. .
Review eighth week lab assignment /etc/sysconfig/keyboard Used to configure the keyboard. /etc/sysconfig/mouse This file is used to specify information about the available mouse. /etc/sysconfig/network Used to configure networking options. /etc/rc. d/rc. local This file is executed after the other init scripts. Put commands that performs some system customization.
Review eighth week lab assignment /etc/fstab - The fstab file is read by software applications. It is the duty of the system administrator to create and accurately maintain this file. - Each file system is described on a separate line. - Fields on each line are separated by tabs and spaces. - # comments - The order in which these records are listed is important.
Review eighth week lab assignment etc/fstab /dev/vg 00/root / ext 3 defaults 11 LABEL=/boot ext 3 defaults 12 none /dev/pts devpts gid=5, mode=620 00 /dev/vg 00/home ext 3 defaults 12 /dev/vg 00/opt ext 3 defaults 12 none /proc defaults 00 none /dev/shm tmpfs defaults 00 /dev/vg 00/tmp ext 3 defaults 12 /dev/vg 00/usr ext 3 defaults 12 /dev/vg 00/var ext 3 defaults 12 /dev/vg 00/swap defaults 00 /dev/cdrom /mnt/cdrom udf, iso 9660 noauto, owner, kudzu, ro 00 /dev/fd 0 /mnt/floppy auto noauto, owner, kudzu 0 0 /dev/vg 02/shome /export/home ext 3 defaults 12 #/dev/vg 01/oracle /mnt/pkg 1/oracle ext 3 noauto 12 #NOTICE: oracle and shome are shared storage. Make sure they are not mounted # on the other side before mounting.
Review eighth week lab assignment Field description of /etc/fstab 1 st field describes the block special device or remote file system to be mounted. 2 nd field describes the mount point for the file system. 3 rd field describes the type of file system. 4 th field describes the mount options associated with the file system. 5 th field describes which file systems will need to be dumped by the dump() command. 6 th field is used by fsck to determine the order in which the file systems are checked at boot time.
Review eighth week lab assignment File Systems File systems are usually mounted read-only. This makes it possible to check the file system while it is mounted; it is not a good idea to check a file system that is mounted read-write.
Review eighth week lab assignment Fsck Command • Fsck utility checks the file system’s consistency, reports any problems it finds, and optionally repairs them. • On many legacy systems such as BSD style systems, the fsck command is invoked automatically on boots and reboots. • Format: fsck [options] device • The kernel supports the following file systems: Demonstrate: /proc cat filesystems
Review eighth week lab assignment Fsck Utility The exit code returned by fsck is the sum of the following conditions: 0 - No errors 1 - File system errors corrected 2 - System should be rebooted 4 - File system errors left uncorrected 8 - Operational error 16 - Usage or syntax error 32 - fsck canceled by user request 128 - Shared library error
Review week eight lab assignment Rpm Package Manager Red Hat Package Manager (rpm) is a package management system. Free software tool which installs, updates, uninstalls, verifies and queries other software packages in this format.
Review week eight lab assignment Package Advantages 1. Used in a uniform way for the user to install programs 2. Uninstalling programs is simple 3. Non-interactive installation makes it easy to automate 4. Original source archive (e. g. . tar. gz, . tar. bz 2) 5. Packages can be cryptographically verified with AES, and MD 5.
Review week eight lab assignment File Representation A file format is a particular way to encode information for storage in a computer file. Disk drives or computer storage are represented in bits. A computer must convert information to 0 s and 1 s and vice-versa. A computer file format can be represented as either a binary image or ASCII file. ASCII is used on most PCs and Macintoshes. EBCDIC (Extended Binary-Coded Decimal Interchange Code is an IBM code for representing characters as numbers. IBM uses EBCDIC widely on large computers.
Review week eight lab assignment File Representation Binary image files represent 256 different binary codes.
Review week eight lab assignment Binary image files use to be able to represent more character codes than ASCII because eight bit bytes were used, whereas ASCII files used seven bits. Now Extended ASCII uses eight bit bytes and can represent 256 character Executable software, mostly word processing files and databases, spread sheets and multimedia files are binary. However, text and source program files as well as HTML and XML files are ASCII.
Review week eight lab assignment The Internets SMTP mail protocol supports only ASCII. When a binary file is attached to an email message, the 8 -bit format is converted to a temporary 7 -bit format to pass through the mail servers. Encoding formats such as MIME, at the receiving end converts the 7 -bit format back into 8 -bit binary format. The 8 -bit to 7 -bit conversion makes files larger as they traverse the Internet.
Review week eight lab assignment Different file formats for different kinds of information. JPEG format – designed to store static photographic images. GIF format – designed to store still images and simple animation. Quick. Time format – designed as a container for many different types of multimedia.
Week nine expected outcomes Upon successful completion of this module, the student will be able to: • Analyze processes of startup and shutdown. • Apply startup scripts and controls to tune system. • Describe basic "autonomous" processes in UNIX.
Next Lab Assignment Initializing or Booting a System 1. CPU is pre-set to RESET mode 2. CPU pre-programmed to seek 0 xfffffff 0 address location 3. BIOS reads MBR (Track 0, Sector 1) 4. First part of MBR contains the boot partition table and executable code 5. Second part of the MBR is used to locate the boot loader. It resides on the “active” partition known as the Boot Sector. 6. Device drivers are loaded (initrd-2. 4. 20 -8. img) 7. Kernel is invoked 8. Init process invoked
Next Lab Assignment Linux Boot Procedure 1. The system startup stage depends on the hardware device that Linux is being booted on. Floppy disk, CD-ROM, a partition on a hard disk, a device on the network, or a USB flash memory stick. Linux is usually booted from a hard disk. 2. After the system locates the boot device, the first part of the boot loader is loaded into RAM and executed. Normally, the first part of the boot loader is less than 512 bytes and is responsible for loading the second part of the boot loader.
Next Lab Assignment Linux Boot Procedure 3. The first 446 bytes are considered the primary boot loader, which contains both executable code and error message text. 4. The second sixty four bytes are the partition tables, which contains a record for each of the four partitions. 5. The last two bytes are the magic number which serves as a validation check of the Master Boot Record (MBR).
Next Lab Assignment Linux Boot Procedure 6. When the second part of the boot loader is loaded into RAM and executed, a pop up screen displays Linux and the optional initial RAM being loaded into memory. 7. The second part of the boot loader is called the kernel loader. After the boot images are loaded, the second part of the boot loader passes control to the kernel image. At this point, the kernel is decompressed and initialized.
Next Lab Assignment Linux Boot Procedure 8. The second part of the boot loader checks the system hardware, lists attached hardware devices, mounts the root device, and loads the kernel modules.
Next Lab Assignment Master Boot Record (MBR) The MBR is not located in a partition, it is located at a Main Boot Record area in front of the first partition. When a data storage device has been partitioned with the MBR Partition Table scheme the master boot record contains the primary partition entries in its partition table. By convention, there are exactly four primary partition table entries in the MBR Partition Table scheme.
Next Lab Assignment Boot Loaders The following directory contains the different Linux boot loader and alternate loaders: Demonstrate: /boot/grub The Linux Loader (LILO) is the combination of parts one and two boot loaders. Because of some disadvantages in the LILO loader, the GRand Unified Bootloader (GRUB) has become more widely used.
Next Lab Assignment Kernels Display a list of available kernels with soft links from /etc/grub. conf and /boot/grub/menu. 1 st. Demonstrate: /etc/grub. conf This is a symbolic link to /boot/grub. conf
Next Lab Assignment Init Process Location: /sbin/init First process to execute in user space Executes: background Process ID: 1 (one) Parent Process ID: 0 (zero) Owner: root Demonstrate: pid_ppid. sh (use two putty windows) Highlight the relationship of the init process to all other executing processes.
Next Lab Assignment # inittab This file describes how the INIT process should set up the system in a certain run-level. # Author: Miquel van Smoorenburg,
Next Lab Assignment # Default runlevel. The runlevels used by RHS are: # 0 - halt (Do NOT set initdefault to this) # 1 - Single user mode # 2 - Multiuser, without NFS (The same as 3, if you do not have networking) # 3 - Full multiuser mode # 4 - unused # 5 - X 11 # 6 - reboot (Do NOT set initdefault to this)
Next Lab Assignment id: 3: initdefault: # System initialization. si: : sysinit: /etc/rc. d/rc. sysinit l 0: 0: wait: /etc/rc. d/rc 0 l 1: 1: wait: /etc/rc. d/rc 1 l 2: 2: wait: /etc/rc. d/rc 2 l 3: 3: wait: /etc/rc. d/rc 3 l 4: 4: wait: /etc/rc. d/rc 4 l 5: 5: wait: /etc/rc. d/rc 5 l 6: 6: wait: /etc/rc. d/rc 6
Next Lab Assignment # Trap CTRL-ALT-DELETE ca: : ctrlaltdel: /sbin/shutdown -t 3 -r now # When our UPS tells us power has failed, assume we have a few minutes # of power left. Schedule a shutdown for 2 minutes from now. # This does, of course, assume you have powerd installed and your # UPS connected and working correctly. pf: : powerfail: /sbin/shutdown -f -h +2 "Power Failure; System Shutting Down“
Next Lab Assignment # If power was restored before the shutdown kicked in, cancel it. pr: 12345: powerokwait: /sbin/shutdown -c "Power Restored; Shutdown Cancelled“ # Run gettys in standard runlevels 1: 2345: respawn: /sbin/mingetty 1 2: 2345: respawn: /sbin/mingetty 2 3: 2345: respawn: /sbin/mingetty 3 ###4: 2345: respawn: /sbin/mingetty 4 ###5: 2345: respawn: /sbin/mingetty 5 ###6: 2345: respawn: /sbin/mingetty 6
Next Lab Assignment # Run xdm in runlevel 5 x: 5: respawn: /etc/X 11/prefdm -nodaemon
Next Lab Assignment Linux Performance Tools sar command is performance monitoring tool. It can find out what Linux is doing all the time. It can generate report and email them to sys admin. vmstat command that reports information about processes, memory, paging, block IO, traps, and cpu activity. free command displays the total amount of free and used physical and swap memory in the system, as well as the buffers used by the kernel.
Next Lab Assignment Linux Performance Tools iostat command is used for monitoring system input/output device loading by observing the time the devices are active in relation to their average transfer rates i. e. it is useful to monitor disk throughput.
Next Lab Assignment Linux system run level modes 0 - Halt system 1 – Single user 2 – Multi-user mode 3 – Full multi-user 4 – unused 5 – X 11 6 - Reboot Shutdown command shutdown Review the Startup/Shutdown lab assignment
Next Lab Assignment /etc/rc. d init. d rc 0. d rc 2. d rc 4. d rc 6. d rc. sysinit rc rc 1. d rc 3. d rc 5. d rc. local /etc rc rc 0. d rc 1. d rc 2. d rc 3. d rc 4. d init. d rc 5. d rc. sysinit rc 6. d rc. local
Next Lab Assignment Activities managed by the kernel Responsive - users Autonomous - daemons The kernel consists of a collection of low level procedures. These procedures are called system calls and they are the primary means for a program to interact with other parts of the system. Explain the difference between the K and S as a script prefix. Demonstrate Execution of the newuid. pl and process. sh scripts Provide examples of pids and ppids (pid_ppid. sh)
Next Lab Assignment Shell Commands df (disk space usage) df –i (file system inode utilization) history (list commands previously input) tail (read records at end of file) head (read records at start of file)
Break-out problems • • What functionality does the mingetty or getty perform? Define the kernel responsive and autonomous functions? What system functionality does the /etc/fstab file provide? What is the functionality does the /etc/sysconfig directory provide? • What functionality does the /etc/inittab file provide? • Commands ls -li who -r kill –l uptime w telinit sleep
Upcoming deadlines Lab Assignment 13 -1 Public Domain/Open Software Evaluation Bulletin Board: Open Source Presentation Sign Up No two presentations shall be the same. Lab assignment grade components. Paper: 0 – 75 points Presentation 0 – 25 points Presentation dates: April 4 April 11 (week 14) ( week 15)
Upcoming deadlines • Lab Assignment 8 -1, Installation Exercise due March 6, 2011 • Lab Assignment 9 -1, Startup/Shutdown due March 13, 2011 • Lab Assignment 10 -1 and 10 -2, Account/LDAP and Process Exercise Scripts due March 20, 2011. • Lab Assignment 11 -1, Knoppix File System Exercise is due March 27, 2011 • Final exam outline will be available on March 13, 2011. • Module 5, System Startup and Shutdown is for week 9.
Lab assistance, questions and answers • Questions • Comments • Concerns • I am available after this Franklin Live session to discuss any problems and/or concerns regarding the lab assignments