This document discusses shell programming and system administration. It provides an overview of shell scripts, their purpose, and common operations. It also describes the system architecture including hardware, kernel, shell, and utilities. Details are given on VMware, Fedora OS, Python, and various file system commands for system administration tasks.

1. SHELL
PROGRAMMING
System Management
By
Gaurav. M. Raikar
EL-18-12

2. • A shell program or script is a computer program
designed to be run by the Unix shell, a
command-line interpreter.
• The various dialects of shell scripts are
considered to be scripting languages.
• Typical operations performed by shell scripts
include file manipulation, program execution,
and printing text
Shell Programming

3. SYSTEM ARCHITECTURE

4. Hardware layer
Hardware layer consists of all peripheral devices (RAM/ HDD/ CPU etc.)
Kernel
• It is the core component of Operating System.
• It interacts directly with the underlying hardware and provides low level services
to upper layer components.
• It manages the resources of Linux such as file management, multitasking,
memory & I/O management
Shell
• Shell is an interface between a user and the kernel, hiding complexity of kernel's
functions from users.
• The shell takes commands from the user and executes kernel's functions.
• shell gets started when the user logs in or start the terminal.
Utilities
• Utility programs that provide the user most of the functionalities of an operating
systems.

5. Vmware & Fedora OS
• VMware Workstation is a hosted hypervisor that runs on
x64 versions of Windows and Linux operating systems; it
enables users to set up virtual machines on a single
physical machine
• Fedora is an open-source operating system built over the
Linux OS kernel architecture.
Fedora is a free to use, customize and distribute. The
operating system is integrated with packaged software and
applications to provide enhanced abilities and functions.
Python
• Python is a high level language like C++, java.
• It is easier to program in python as it is easy to learn and
use, it takes less time to write, programs are shorter and
easier to read.

6. System Administration
• The job of a system administrator is to manage the
operations of a handling files and directories of
computer system.
• An Operating System is designed consisting of system
software meant for different purpose.
• Each process is monitored by the process to know if it
is working properly or not.

7. Session Management
• Its a process of keeping track of activity across
sessions of interactions with the computer system.
• Typically sessions management include keeping
track of applications open and thread handled.
• A desktop is a program that saves contents and
keep it for further use.

8. FILE SYSTEM COMMANDS

9. System Related Commands
Who: shows who is logged in
Who am I :Shows the name of current user logged in
who -b: Shows the user list
Date : Shows the current date and time
ps -ef : Gives the full information of each running process
Up-time : Tells how long it has been since the system has been powered ON.
Last : shows Session In.
Last User : Shows Information Of Login session Of Last User
Free : Shows the free ,used memory on system

10. import os
import sys
import time
print "who am i"
print os.system('who am i')
print os.system('uname -airvms')
print "todays date and time"
print os.system ('date')
print "who has logged in the system"
print os.system('who -b')
print os.system('w')
print "full information about each of
the process currently running"
print os.system('ps -ef')
print "user oriented information"
print os.system('ps -u')
print "list information about files"
print os.system('ls -ls')
print "memory usage chart"
print os.system('free')
print " memory usage chart in human
readable format "
print os.system('free -h')
print "see how long the system has been
power up"
print os.system('uptime')
print "uptime in pretty format"
print os.system('uptime -p')
print "information about last logged in
session"
print os.system('last -f/var/log/wtmp')
print "get information of the session only
of the user "
print os.system('last user ')
print "information of the session with full
user name and domain name "
print os.system('last -w')
print "get information of the session with
the full user name and information about
last session"
print os.system('last reboot')
Program

11. Output