how ubuntu works???
DESCRIPTION
This presentation is about UbutnuTRANSCRIPT
-By Arpan Chavda09BCE006
Boot loaderDesktop ManagementFile systemsSoftware ManagementFile structure SecurityConclusionMy Achievements
Outline
Ubuntu (Most of all Linux) uses GRUB(Grand Unified Boot loader) which is developed under GNU project.
Latest version:GRUB2It will generate Booting Entries resides in all
partitions and write onto MBR.dynamically configurable config file:/boot/grub/grub.conf “sudo update-grub” to update grub.
Boot Loader
boot.img is stored in the MBR or Volume boot record and it will load like Stage 1.
This loads the first sector of core.img (generated from diskboot.img) which is then used to load the rest of the generated core.img file.
How GRUB2 works?
The core.img file will normally be stored in the same location as Stage 1.5(GRUB Stage 1.5 is located in the first 30 kilobytes of hard disk immediately following the MBR and before the first partition)
Once loaded, the core.img file will load the default configuration file and any other modules needed in stage 2.
Desktop management contain basic tools for essential operations like login,file managing,UI,etc.
Login manager: GDM for older ubuntu and LightDM for Ubuntu 11.10
File manager: Nautilus File managerFor Ubuntu 11.04 or Ubuntu 11.10 it contain
Its own Desktop Interface called “Unity”.
Desktop Management
KDE: More functionality,Higher RAM usage than other,animations,etc
GNOME: Compact,slick,easy to useXFCE:Easy to use,faster,low power
usage,etcLXDE:Very light,compact,Lowest RAM Usage
than others,low power usage
Desktop Environments
Ubuntu uses EXT journaling file system.A journaling file system is a file system that
keeps track of the changes that will be made in a journal (usually a circular log in a dedicated area of the file system) before committing them to the main file system. In the event of a system crash or power failure, such file systems are quicker to bring back online and less likely to become corrupted.
File systems
Comparisons of EXTs
File system
Maximum filename
length
Allowable characters in
directory entries
Maximum pathname
length
Maximum file size
Maximum volume size
ext2ext2 255 bytes Any byte except NULL
and /
No limit defined
16 GB to 2 TB
2 TB to 32 TB
ext3 255 bytes Any byte except NULL
and /
No limit defined
16 GB to 2 TB
2 TB to 32 TB
ext4 256 bytes Any byte except NULL
and /
No limit defined
16 GB to 16 TB
1 EB (but user tools
limited to 16 TB)
Software management Synaptic package manager: It is software manager to install or remove
software in all Linux systems. Ubuntu software centre: It is software manager created by Ubuntu
team which contain software list with attractive user interface with managed things.
How USC works? APT(Advance packaging Tool): It is a CLI
that works with core libraries to install and remove software in a system.
Command: sudo apt-get install “soft-name” PPA(Personal Package Archive):It is a
software repository used to manage software in a system.
PPA is trustworthy rather that grabbing exe from untrusted site in windows systems.
File structure
Root Directory:/
/bin
/boot
/dev /etc
/home /lib
/media
/mnt
/tmp
/sys
/usr
/var
Root DirectoryBegins filesystem structure
/usrHolds subdirectories that support userAdministrative applicationlibraries
/mediaUsed for mount pointsMount CD-Rom, DVD,floppy
/mntUsed for mount pointsMount filesystem (windows partition)
/homeHold home directoriesLike user account
/var Holds files and directories that frequently changeLike web server files, log files, printer spool file
Security Most Linux system is safe and secure. Most Trojans and viruses are made to attack
on windows systems You can use “Firestarter”(Firewall software)
and ClamTK(Antivirus scanner).
Conclusion Ubuntu is used at server level but it has no
major PC Market(3%) compared to windows.It is increasing nowadays.
Today's Ubuntu is more user friendly rather than previous Ubuntu versions.
My Achievements
I. Gbuntu(Genius+Ubuntu)My Linux Operating system based on ubuntu
10.04.3 http://sites.google.com/site/gbuntuproject
I. My first ubuntu appSimple app describing about gbuntu.Using python and GTK+ Environment.
References GNU Project site Ubuntu Forums IBM guide for Linux file systems GRUB2 Guide Ubuntu 10.10 official User guide Ubuntu wikis
ANY Q???
THANK YOU