Transcript Week_Eight_8_UNIX_ppt - Computing Sciences

Week Eight Agenda
Announcements
Link of the week
Display inode information
This week’s expected outcomes
Next lab assignment
Break-out problems
Upcoming deadlines
Lab assistance, questions and answers
Week Eight Agenda
Announcements:
Everyone should have a grade recorded for the
midterm exam. If not, please email me.
The final exam is worth 200 points. It covers more
information and has more questions. The final exam is
not compressive. Only about 5 - 6 percent of the
previous material will be on the final exam.
Sign up for your open source topic and email me the
week you would like to do your presentation on
(week 14 or 15).
Link of the week
http://bhami.com/rosetta.html
A Sys Admin's Universal Translator (ROSETTA
STONE) OR What do they call that in this world?
Tasks
OSs
Adm. GUI
AIX
File System
A/UX
Kernel
FreeBSD
Start up scripts
HP-UX
Create a file system
Linux
Mount CDROM
NCR Unix
Add software
Open BSD
Mac OS X
Link of the week
http://support.apple.com/kb/HT1148?viewlocale=en_US
Software Installation Quick Assist for Mac OS X
is a great toolbox that organizes and supports your
software collection.
Link of the week
Open Source Projects
http://sourceforge.net
http://freshmeat.net
Lab Assignment 13-1 Public Domain/Open Software
Evaluation is due December 9, 2012.
Requirements:
APA Style format
Cover sheet (course, instructor name, topic)
Three typed pages of information (min)
Reference page
Link of the week
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:
December 3, 2012 (week 14)
December 10, 2012 (week 15)
Week Seven Question
How can the inode attributes be displayed?
There is a good deal of information about individual
files on a UNIX system. One way to display this
information is through a Perl script.
The Perl stat command is used to access thirteen pieces
of information about a file through a script.
($dev, $ino, $mode, $nlink, $uid, $gid, $rdev, $size,
$atime, $mtime, $ctime, $blksize, $blocks) = stat (
$fileattributes);
Week Seven Question
$dev – device number of the filesystem (0)
$ino – inode number (1)
$mode – file mode (permissions) (2)
$nlink – number hard links (3)
$uid – user ID of file’s owner (4)
$gid – group ID of file’s owner (5)
$rdev – device identifier (6)
$size – total size of file (7)
$atime – last access time in seconds since epoch (8)
$mtime – last modified time in seconds since epoch (9)
$ctime – inode change time in seconds since epoch (10)
$blksize – block size for file syatem (I/O) (11)
$blocks – actual number of blocks allocated (12)
Week Seven Question
Single file attribute (permissions):
$mode=(stat($fileattributes))[2];
Single file attribute (date) and print:
@date=stat ($fileattrabutes);
print “$date[4]\n”;
Perl module :
use File::stat
Review week seven lab assignment
Define: Data structure is where information is
stored/collected in one place. The stored
information may or may not be related.
Data structures are unique in their construction
so as to deliver a specific usage. Commonly
data structures are arrays, hash tables, stacks,
and queues.
Review week seven lab assignment
The inode data structure. Use ls –i command to display
attributes.
file mode – file permissions (rwx)
count of hard links – how many hard links point
to the inode
file type – executable, block special
owner id
group id
time of last file access - timestamp
time of last file modification - timestamp
file size - bytes
file addresses – addresses of the blocks of
storage containing the files data on a HDD
Review week seven lab assignment
Review week seven lab assignment
• The directory maps file names to inodes.
• Each file has one inode.
• The number of inodes is a kernel parameter
value set manually or dynamically by the
operating system.
• Each file may have more than one directory
entry.
• Inodes contain a list of disk block addresses.
• All inodes are data structures
Review week seven lab assignment
Review week seven lab assignment
• When there are multiple hard links, more directory entries
point to the same inode or file name.
• An inode can only hold a fixed number of direct data block
addresses (10 for Linux). Large files use indirect block
addresses.
• The inode keeps a count of the number of hard links that point
to it.
• Deleting a file deletes an entry from a directory.
• If the number of hard links is 1, removing or deleting this file
will also delete the inode.
Review week seven lab assignment
Define: A physical link (hard) refers to the specific
location of physical data.
Command: ln <original file name> <new file name>
ln test_file_1 test_file_1_hard_link
-rwx------ 2 dandrear faculty 20 Oct 21 11:37 test_file_1
-rwx------ 2 dandrear faculty 20 Oct 21 11:37 test_file_1_hard_link
Review week seven lab assignment
Review week seven lab assignment
Define: A symbolic link is a link to a directory or to a
file in a different file system. A symbolic path
indicates the abstract location of another file.
Command: ln –s <original file name> <new file name>
ln –s test.txt test_symbolic_link
-rwx------ 1 dandrear faculty 20 Sep 4 16:44 test.txt
lrwxrwxrwx 1 dandrear faculty 8 Oct 18 19:31 test_symbolic_link -> test.txt
Review week seven lab assignment
Define: tar
tar –cf newpack.tar /export/home/dandrear
tar –xvf origpack.tar
tar –tvf origpack.tar
Define: gzip
gzip filename.tar
gzip –d filename.tar.gz
gunzip filename.tar.gz
Define: bzip2/bunzip2ip
bzip2 filename.tar
bunzip2 filename.tar.bx2
Review week seven lab assignment
Installing the software package
Package
FreeBSD Port
Usually, the source files are packaged in a
compressed archive file (.tar.gz). After
downloading, the .tar.gz file, use the tar tool to
uncompress the un-package the source files.
Review week seven lab assignment
Definition: Installation of computer programs.
Installation process:
- Condensed package
- Unpack package
- Customized package
- Test the functionality of the system
- Configure files
Review week seven lab assignment
Two choices for installing a project
1. Install binaries from a package
called “rpm” in Red Hat.
rpm checks for dependencies and
conflicts with other installed
packages on the system.
Review week seven lab assignment
2. Install from source code
Allows for custom installations
Allows for code modifications
Optimum compilation for target
platform
Review week seven lab assignment
The RPM Package Manager (RPM) is a
powerful command line driven package
management system capable of installing,
uninstalling, verifying, querying, and updating
computer software packages. Each software
package consists of an archive of files along
with information about the package like its
version, a description, and the like. There is
also a library API, permitting advanced
developers to manage such transactions from
programming languages such as C or Python.
Review week seven lab assignment
rpm is a tool
rpm –q sloccount (query to see if tool
exists)
If the tool isn’t on your system, create a
directory named sloccount
Download name sloccount-2.231.i386.rpm
rpm –vUh sloccount-2.23-1.i386.rpm
(install tool)
See the man page regarding the rpm tool
Review week seven lab assignment
QUERYING AND VERIFYING PACKAGES:
rpm {-q|--query} [select-options] [query-options]
rpm {-V|--verify} [select-options] [verify-options]
rpm --import PUBKEY ...
rpm {-K|--checksig} [--nosignature] [--nodigest]
PACKAGE_FILE ...
INSTALLING, UPGRADING, AND REMOVING PACKAGES:
rpm {-i|--install} [install-options] PACKAGE_FILE ...
rpm {-U|--upgrade} [install-options] PACKAGE_FILE ...
rpm {-F|--freshen} [install-options] PACKAGE_FILE ...
rpm {-e|--erase} [--allmatches] [--nodeps] [--noscripts]
[--notriggers] [--repackage] [--test] PACKAGE_NAME ...
Review week seven lab assignment
Software Installation of UNIX/Linux typically go
something like this:
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Download the software, which might be distributed
in source code format, or as a binary.
Unpack the software from its distribution format
(typically a tarball compressed with compress, gzip,
or bzip2
Locate the documentation (perhaps an INSTALL or
README file, or some files in a doc/ subdirectory)
and read up on how to install the software.
If the software was distributed in source format,
compile it. This may involve editing a makefile, or
running a configure script, and other work.
Test and install the software.
Review week seven lab assignment
Software releases
Interfaces – normally remain the constant.
Implementations – actual fixes
Behaviors – system changes from one
implementation to another
Review week seven lab assignment
Kernel is the central component of most operating
systems. It’s responsibility is to manage the system’s
resources and communicate between the hardware
and software.
Kernel space is allocated for the kernel. Users aren’t
able to access this area. Kernel space is generally
larger than user space.
User space is a memory area where all user mode
applications are performed. This memory area is
swappable if necessary.
Review week seven lab assignment
UNIX/Linux Turnable Parameters
Number of users on a system
Maximum database size
Number of global buffers
Number of semaphores (e.g. train track)
Set shared memory allocation
Display: Kernel Tunable Parameters are located under
the /proc/sys directory.
Review week seven lab assignment
Buffer cache
Amount of memory used to transfer a file system
data structure such as inodes, direct blocks,
indirect blocks, and cylinder groups.
Initially, you want to set up the buffer cache large
enough to handle an inode data structure.
Week eighth expected outcomes
Upon successful completion of this module
(weeks 6, 7, and 8), the student will be able to:
• Create make file scripts for software programs.
• Use pattern rules in make files.
• Create an effective PowerPoint presentation.
• Create make files with multiple targets.
• Install software packages on a server.
Next Lab Assignment
fsck
fsck is used to check and optionally repair one or
more Linux file systems.
If no filesystems are specified on the command line,
and the -A option is not specified, fsck will
default to checking filesystems in /etc/fstab serial.
fsck -A
Walk through the /etc/fstab file and tries to check all
file systems in one run. This option is typically used
by the /etc/rc system initialization file, instead of
trying to use multiple commands for checking a
single file system.
Next Lab Assignment
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
/etc/fstab
Next Lab Assignment
/dev/mapper/vg_system-root
/
ext4 defaults
UUID=5a9e44d8-7554-4d9d-bf16-a1b6cf48ff9e /boot ext4 defaults
/dev/mapper/vg_system-home /home
ext4 defaults
/dev/mapper/vg_system-tmp /tmp
ext4 defaults
/dev/mapper/vg_system-usr
/usr
ext4 defaults
/dev/mapper/vg_system-var /var
ext4 defaults
/dev/mapper/vg_system-swap swap
swap defaults
/dev/shm
tmpfs defaults
devpts
/dev/pts
devpts gid=5,mode=620
sysfs
/sys
sysfs defaults
proc
/proc
proc defaults
dc2prst001.students.qw.franklin.edu:/vol/dc2_einstein_home/home /home nfs defaults
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Next Lab Assignment
/etc/config Directory
The /etc/sysconfig directory is where many of the
files that control the system configuration are stored.
This section lists these files and many of the
optional values in the files used to make system
changes.
Next Lab Assignment
/etc/sysconfig
authconfig gpm
ip6tables-config netdump_id_dsa
rawdevices
autofs
grub
iptables-config netdump_id_dsa.pub
rhn
clock
harddisks irqbalance
apm-scripts
devlabel.d installinfo
netdump
prelink
network
sendmail
console
hwconf
keyboard
networking
syslog
crond
i18n
kudzu
network-scripts sysstat
devlabel init
mouse
ntpd
xinetd
Next Lab Assignment
The Installation Exercise is an exercise that requires
following directions. Perform each step in the
prescribed sequence and using the installation syntax
from this slide presentation.
Create an ASCII file named 4th_log.txt
Create the following directory
/$HOME/itec400/homework/4th
Download the programming language “forth”
Copy compressed “tar” file to your 4th directory
cd /$HOME/itec400/homework/4th
cp ~dandrear/public_html/itec400/Misc/4th-3.3d2-unix.tar.gz .
The expected output is an executable file called “4th”.
Next Lab Assignment
Grading Criteria
The size of the file “readme.txt” is recorded in
“4th_log” : 0 – 15 points
The prerequisites for the target ‘4th’ are
recorded in “4th_log”: 0 – 15 points
The size of the executable named “4th”, in
bytes, is recorded in “4th_log”: 0 – 20 points
Next Lab Assignment
Demonstrate Power Point Presentation
Fall 2012 Online Unix System Administration
Wireshark
PDF Creator
Password Safe
Break-out problems
1. Process ID
2. User ID
3. fsck
4. /etc/fstab
5. Turnable parameters
6. Multiuser runlevel (Linux)
7. /boot/vmlinuz-*
8. Single user mode
9. /var/mail/dandrear
10. inode
11. ASCII
12. crond
13. shared memory
14. semaphore
15. /etc/sysconfig
16. /proc directory
17. UTC
Upcoming deadlines
• Lab Assignment 6-1, Programming
Assignment I due October 28, 2012.
• Lab Assignment 8-1, Installation Exercise due
November 4, 2012..
• Lab Assignment 9-1, Startup/Shutdown due
November 11, 2012.
• Read Module 4 for week 8.
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