Transcript Week_8

Week Eight Agenda
Announcements
Link of the week
Review week seven lab assignment
This week’s expected outcomes
Next lab assignment
Upcoming deadlines
Lab assistance, questions and answers
Link of the week
http://bhami.com/rosetta.html
A Sys Admin's Unixersal 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
Link of the week
Open Source Projects
http://sourceforge.net
http://freshmeat.net
Lab Assignment 13-1 is due April 8 (100 points)
Requirements:
APA Style format
Cover sheet
Three sheets of typed information
Reference page
Link of the week
Lab Assignment 13-1 Public Domain/Open
Software Evaluation
No two presentations shall be the same.
Lab assignment grade components.
Paper: 0 – 75 points
Presentation 0 – 25 points
Presentation date:
April 2
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
inode
The inode data structure
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 (same 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 and entry from a directory.
• If the number of hard links is 1, removing or deleting that file
will also delete the inode.
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
indicating the abstract location of another file.
ln –s <original file name> <new file name>
lrwxrwxrwx 1 root
lrwxrwxrwx 1 root
root
root
10 Jun 28 2005 rc0.d -> rc.d/rc0.d
10 Jun 28 2005 rc1.d -> rc.d/rc1.d
Define: A physical link (hard) refers to the specific
location of physical data.
ln prog1 prog2
-rwx------ 2 varneyg faculty
-rwx------ 2 varneyg faculty
318 Jun 14 21:03 prog1
318 Jun 14 21:03 prog2
Review week seven lab assignment
Define: tar
tar –cf newpack.tar /export/home/varneyg
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
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 (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.
2. Install from source code
• Allows for custom installations
• Allows for code modifications
• Optimum compilation for target platform
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-2.23-1.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 goes
something like this:
1.
2.
3.
4.
5.
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
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
Turnable Parameters
Unix/Linux kernel
semmni, semmns, and semmsl reflect the
number of semaphores per set/Cache uses
shmmax, shmmni, shmseg, and shmall
reflect shared memory allocation
maxusers, pt_cnt, use_mxcc_prefetch
Example of semaphore.
train track
Review week seven lab assignment
File Systems (CDFS, MEMFS, NAMEFS, NFS, SFS, S5, UFS,
VXFS)
Buffer cache
Amount of memory used to transfer a file system
data structure such as inodes, direct blocks,
indirect blocks, and cylinder groups.
Review week seven lab assignment
Software releases
Interfaces – normally remain the constant.
Implementations – actual fixes
Behaviors – system changes from one
implementation to another
Week eighth expected outcomes
Upon successful completion of this module, 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
Walks through the /etc/fstab file and tries to check all
file systems in one run. This option is typically used
from the /etc/rc system initialization file, instead of
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
Next Lab Assignment
/etc/fstab
/dev/mapper/vg_system-root /
ext4 defaults
11
UUID=5a9e44d8-7554-4d9d-bf16-a1b6cf48ff9e /boot
ext4 defaults
12
/dev/mapper/vg_system-home /home
ext4 defaults
12
/dev/mapper/vg_system-tmp /tmp
ext4 defaults
12
/dev/mapper/vg_system-usr /usr
ext4 defaults
12
/dev/mapper/vg_system-var /var
ext4 defaults
12
/dev/mapper/vg_system-swap swap
swap default
00
tmpfs
/dev/shm
tmpfs defaults
00
devpts
/dev/pts
devpts gid=5,mode=620
00
sysfs
/sys
sysfs defaults
00
proc
/proc
proc defaults
00
dc2prst001.students.qw.franklin.edu:/vol/dc2_einstein_home/home /home nfs defaults 0 0
Next Lab Assignment
The Installation Exercise is an exercise that requires
following directions. Perform each step in the
prescribed sequence and syntax.
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 ~varneyg/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.txt” : 0 – 15 points
The prerequisites for the target ‘4th’ are
recorded in “4th_log.txt”: 0 – 15 points
The size of the executable named “4th”, in
bytes, is recorded in “4th_log.txt”: 0 – 20
points
Upcoming deadlines
Programming Assignment 1, 6-1 is due Feb. 26.
Installation Exercise, 8-1 is due March 4.
Startup/Shutdown, 9-1 is due March 11.
Account/LDAP Script, 10-1 is due March 18.
Process Exercise, 10-2 is due March 18.
Demonstrate Power Point Presentation
http://cs.franklin.edu/~varneyg/itec400/PowerPoints/fre
ejava.ppt
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