1. Linux
Introduction
August 2012

2. Agenda
History
Introduction
Partition
FileSystem
Permission
Commands

3. History
• Unix (very expensive)  Minix (for students)
• Enter Linus Torvalds – Linux Kernel
• With GNU’s Richard Stallman – Bash Shell
• Linux Kernel + Shell = GNU/Linux
• “Linux is obsolete” - Andrew Tanenbaum, 1992
– Monolithic kernel
– Multithreading file system is useless
• Cost to rebuild: $1.4 Billion = 6 million lines of
code
• In 87% of Servers and supercomputers
• The Open Source Initiative

4. Introduction
• Cheap
• Huge community
• Open source
• Presence of mind
• Jobs
• Better understanding

5. Introduction
• Monolithic Kernel
• bash, sh, ksh, csh - CLI
• X Windows + Gnome, KDE
• Ext2, ext3, ext4 File System
• Everything is a file
• Multi-user – Built to last
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6. Linux Kernel
• Monolithic Kernel – Resource Manager
for process, memory or hardware.
• Process – Threads, POSIX
• Memory – page size, swapping
• Virtual file system
• Every major protocols supported in
Linux – SCTP, TCP, VPN, IP Tunnel etc
Anatomy of Linux Kernel: http://www.ibm.com/developerworks/linux/library/l-linux-kernel/?
S_TACT=105AGX59&S_CMP=GR&ca=dgr-lnxw07LKernalAnatomy
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7. Bourne-again shell
There are 10 types of people in this world, who understand binary and
those who don’t.
• Macro processor for commands– The main port of entry
• Default on Linux and Mac OS X
• Interactive and Shell scripting
• Shell script == .bat files (but way more powerful and easier!)
• It’s interpreted - shell reads each line and acts on it immediately
• Automate task, create own command, play with your box!
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8. Distro & Installation
Packages: for example to each Distro
debian: dist
mandrake: Mandrake
redhat: RedHat
suse: suse
fedora: Fedora
images: image of Linux (Kernel modules, installation process/boot,
system recovery
dosutils: some tools for the installation from DOS
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9. File System & Partitioning
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10. File System & Partitioning
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11. File System & Partitioning
A Sample of Paritioning:
/boot 100M
SWAP 512M
/ 2000M
/usr 6000M
/home 1000M
/tmp 2000M
/var remain space
Moreover, Multiple OS/Boot Supported by Linux (LILO – LInux boot
LOader, ...)
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12. File System & Devices
hda1: first partition of first IDE drive
hda2: second partition of first IDE drive
sdc3: third partition of the third SCSI drive
IDE: 4 main partitions & 1 of them could be extended one (allow sub-par).
In Linux: max 64 IDE partitions & 16 SCSI
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13. File System & Devices
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14. File System & Devices
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15. File System & Permission
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16. File System & Permission
$ chmod a=r testfile
(read & wipe out all pers)
-r--r--r—
$ chmod g+x testfile
(execute perm. for group)
-r--r-xr—
$ chmod u+wx testfile
(write & execute for owner)
-rwxr-xr—
$ chmod ug-x testfile
(remove execute for both owner group)
chmod –R 777 directory-name/ -rw-r--r--
d = directory
- = regular file
l = symbolic link
s = Unix domain socket
p = named pipe
c = character device file
b = block device file
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17. File System & Permission
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18. YP New System
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(DB servers, …)
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19. Accumulate & JBoss
Refer other slides pls.
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20. THANK YOU