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The IP addressing is an essential part of networking and to establish an ubuntu cloud it has to be configured CORRECTLY and the default gateway has to be mentioned for communication with other network or same network. To configure the IP addressing the command that can be used is ip, IFCONFIG and route. These are the commands that ALLOW the configuration of the networking. 

To set the configuration use the following command:

sudo ifconfig eth0 10.0.0.100 netmask 255.255.255.0

Through this IP address can be set and configured temporarily to save it PERMANENTLY ifconfig file has to be MODIFIED.

The IP addressing is an essential part of networking and to establish an ubuntu cloud it has to be configured correctly and the default gateway has to be mentioned for communication with other network or same network. To configure the IP addressing the command that can be used is ip, ifconfig and route. These are the commands that allow the configuration of the networking. 

To set the configuration use the following command:

sudo ifconfig eth0 10.0.0.100 netmask 255.255.255.0

Through this IP address can be set and configured temporarily to save it permanently ifconfig file has to be modified.

Cloud computing has a few disadvantages, some of them are:

Security and privacy: The data in ubuntu cloud have many instances with a third party which many users may not prefer. Cloud servers store sensitive information which MUST be protected at all costs. There is a vulnerability of UNAUTHORIZED access.

Loss of control (dependency): In cloud computing the cloud service providers play a major role more maintenance and fixing of the cloud. Being a third party an organization has less control over it. And once a cloud is established migrating to another CSP is not an easy task.

Costs: Although in the long run cloud computing is cheap but being a new technology the improvements and research involved makes it quite expensive. To incorporate this technology many changes may be require INCLUDING the development of software.

Integration and knowledge: As most of the functions are provided by a CSP getting to understand the system from an organizational point of view is tough. ALSO integration with existing SYSTEMS is hard to achieve.

Cloud computing has a few disadvantages, some of them are:

Security and privacy: The data in ubuntu cloud have many instances with a third party which many users may not prefer. Cloud servers store sensitive information which must be protected at all costs. There is a vulnerability of unauthorized access.

Loss of control (dependency): In cloud computing the cloud service providers play a major role more maintenance and fixing of the cloud. Being a third party an organization has less control over it. And once a cloud is established migrating to another CSP is not an easy task.

Costs: Although in the long run cloud computing is cheap but being a new technology the improvements and research involved makes it quite expensive. To incorporate this technology many changes may be require including the development of software.

Integration and knowledge: As most of the functions are provided by a CSP getting to understand the system from an organizational point of view is tough. Also integration with existing systems is hard to achieve.

Ethernet interfaces are the PART of the NETWORKING and it is automatically identified by the SYSTEM using different naming conventions. It is represented by ethX, where X= any numeric value. The default interface of the system is named as eth0 and it will go on after this.

To identify the Ethernet interface the command that is used:

ifconfig -a | grep eth
eth0
Link encap:Ethernet

HWaddr 00:15:c5:4a:16:5aThe command will SHOW all the interfaces that are associated with the system.

Ethernet interfaces are the part of the networking and it is automatically identified by the system using different naming conventions. It is represented by ethX, where X= any numeric value. The default interface of the system is named as eth0 and it will go on after this.

To identify the Ethernet interface the command that is used:

ifconfig -a | grep eth
eth0
Link encap:Ethernet

HWaddr 00:15:c5:4a:16:5aThe command will show all the interfaces that are associated with the system.

Ubuntu enterprise CLOUD includes many FEATURES that are not being provided with the other cloud platforms:

1. It is EC2 compatible cloud PLATFORM that is built on ubuntu SERVER.
2. It provides complete built in cloud solution to manage the on-demand functionality.
3. It provides the features of on-demand access and increases the EC2 functionality.
4. It provides privacy policies and isolation from the hardware devices.
5. It provides an easy way to scale the PUBLIC providers and avoid lock-in whenever possible.

Ubuntu enterprise cloud includes many features that are not being provided with the other cloud platforms:

The three levels that are included in instance isolation:

Networking isolation: it keeps the overall security of the ubuntu cloud system and keeps the NETWORK isolated from the user sight so that there will be less security issues. 

OS isolation: it keeps the user away from the operating system CHANGES. It provides Mandatory Access control (MAC) system that includes default scripts to provide the isolation from the user to the Operating system.

Hypervisor based machine isolation: it doesn’t allow the user to know what kind of hypervisor is used to provide the services which USERS have asked for. It provides intrinsic PROPERTIES to hide its existence from the users of the cloud.

The three levels that are included in instance isolation:

Networking isolation: it keeps the overall security of the ubuntu cloud system and keeps the network isolated from the user sight so that there will be less security issues. 

OS isolation: it keeps the user away from the operating system changes. It provides Mandatory Access control (MAC) system that includes default scripts to provide the isolation from the user to the Operating system.

Hypervisor based machine isolation: it doesn’t allow the user to know what kind of hypervisor is used to provide the services which users have asked for. It provides intrinsic properties to hide its existence from the users of the cloud.

To authenticate and authorize the user there are two steps INVOLVED:

1. User should have access to the cloud CONTROLLER account and access to its user interface.
2. Administrative RIGHTS to the user to create their own policies. 

The registered users get a access key that gives the certificate and the query information to the user which can be used to authorize the user’s status. 

The authentication will vary for each user to access the cloud and its service. To authenticate the user a password will be given to access the web console and RETRIEVE their certificate and query key. Cloud controller verifies the authentication only at the FIRST time but the authorization is verified at each level.

To authenticate and authorize the user there are two steps involved:

1. User should have access to the cloud controller account and access to its user interface.
2. Administrative rights to the user to create their own policies. 

The registered users get a access key that gives the certificate and the query information to the user which can be used to authorize the user’s status. 

The authentication will vary for each user to access the cloud and its service. To authenticate the user a password will be given to access the web console and retrieve their certificate and query key. Cloud controller verifies the authentication only at the first time but the authorization is verified at each level.

There are TWO TYPES of actors that are required for authentication and AUTHORIZATION:

• User or administrator of the system who has the rights to start and stop the instances of the system.
• Components of the systems that are required to be present to fully utilize the requests.
• The authentication on UBUNTU cloud is being performed by X509 certificate that consists of cryptographic keys for authentication and SECURE communications between all the actors.

There are two types of actors that are required for authentication and authorization:

To prevent eavesdropping on network TRAFFIC from a MACHINE run by one user to the machines run by other users, NETWORKING plays an IMPORTANT role in security.

Following networking MODES are available at set-up time, depending on the level of security:

• SYSTEM Mode
• STATIC Mode
• MANAGED Mode
• MANAGED-NOVLAN Mode

To prevent eavesdropping on network traffic from a machine run by one user to the machines run by other users, networking plays an important role in security.

Following networking modes are available at set-up time, depending on the level of security:

The INITIAL addition of Node Controller required a password to EXCHANGE the cryptographic keys from the lower controller to the upper one. After the password is exchanged, all operations RELY on the TRUST PROVIDED by these keys in the communications between the controllers.

The initial addition of Node Controller required a password to exchange the cryptographic keys from the lower controller to the upper one. After the password is exchanged, all operations rely on the trust provided by these keys in the communications between the controllers.

Node controller consists of the hardware settings and configuration for the image machines. It performs the tasks that are REQUESTED by CLUSTER controller and reply to the QUERIES. 

It performs the following tasks:

1. Verify and authenticate the user request.
2. Allow user to download the image from the cache and use it.
3. Create a virtual network interface for easy communication between machines.
4. Start an INSTANCE of a virtual MACHINE that can be accessed by the user.

Node controller consists of the hardware settings and configuration for the image machines. It performs the tasks that are requested by cluster controller and reply to the queries. 

It performs the following tasks:

1. Verify and authenticate the user request.
2. Allow user to download the image from the cache and use it.
3. Create a virtual network interface for easy communication between machines.
4. Start an instance of a virtual machine that can be accessed by the user.

Walrus STORAGE controller uses SOAP API that are compatible with its architecture. 

Its main function is:

• To STORE the machine images that can be used by the cloud controller
• To access and store the DATA from anywhere. 
• It provides file level storage system and doesn’t provide the locking of a file. It doesn’t allow concurrent file to change the status of a single file that is GETTING modified by the user. 
• It SAVES the state of the images.

Walrus storage controller uses SOAP API that are compatible with its architecture. 

Its main function is:

The elements that are INCLUDED in ubuntu cloud architecture are:

Cloud controller: it is the main controller that controls the communication between two nodes and allows the system to communicate with each other.

Walrus Storage controller: It controls the storage of the data and resource at one place for EASY access.

ELASTIC block storage controller: it uses the elasticity concept and allow the resources to scale up as the demand rises. This block consists of dynamic resources. 

Cluster controller: it controls the cloud clusters which are made up of mady nodes and contains the configuration of all the nodes from a single POINT.

Node controller: it consists of the hardware resources that is being provided to the web or to the USER through cluster controller.

The elements that are included in ubuntu cloud architecture are:

Cloud controller: it is the main controller that controls the communication between two nodes and allows the system to communicate with each other.

Walrus Storage controller: It controls the storage of the data and resource at one place for easy access.

Elastic block storage controller: it uses the elasticity concept and allow the resources to scale up as the demand rises. This block consists of dynamic resources. 

Cluster controller: it controls the cloud clusters which are made up of mady nodes and contains the configuration of all the nodes from a single point.

Node controller: it consists of the hardware resources that is being provided to the web or to the user through cluster controller.

Private cloud offers complete set of development tools and easy to configure panel where you can customize and deploy prototype applications. 

• It KEEPS the private sensitive application separate and hidden from the world.
• It provides the provision to create high PERFORMANCE applications and include the concept of elasticity. 
• It uses a firewall and keeps all the resources in a pool that separates them with other resources that are MADE PUBLIC.

Private cloud offers complete set of development tools and easy to configure panel where you can customize and deploy prototype applications. 

The private cloud concept has a variety of usage scenarios. Some of them are :

1. It enables an organization to RAPIDLY develop and also prototype cloudware applications. Also this can be done behind a firewall enabling the creation/development of privacy SENSITIVE applications such as classified data handling.
2. Being an elastic platform it enables the use of high performance applications whose load can be fluctuating. The system is based on aggregated peak loads of DIFFERENT applications at a single point of TIME.
3. By USING private cloud concept the organization can assign a pool of hardware inside the firewall henceforth enabling it to be assigned to the users by a common gui to speed up the process.

The private cloud concept has a variety of usage scenarios. Some of them are :

Ubuntu till date has released three components, they are named as :

• Ubuntu Server EDITION on Amazon EC2 (IAAS)
• Ubuntu enterprise cloud POWERED by Eucalyptus (IaaS)
• UbuntuOne(SaaS)

The first two components are TARGETED for the infrastructure layer of the computer stack. And UbuntuOne is meant for the software layer also known as Software as a service (SaaS).

Ubuntu till date has released three components, they are named as :

The first two components are targeted for the infrastructure layer of the computer stack. And UbuntuOne is meant for the software layer also known as Software as a service (SaaS).

You can USE the command:

1. free -m to DISPLAY output in MB
2. free -g to display output in GB

You can use the command:

USE the COMMAND

PS UX

Use the command

ps ux

To calculate the SIZE of a folder use the COMMAND DU –sh folder1.

To calculate the size of a folder use the command du –sh folder1.

Through BEHAVIOURS tab you can make many changes on the appearance of desktop

Auto hide the launcher : You can use this option to REVEAL the launcher when moving the pointer to the defined HOT spot.

Enable workspaces: By checking this option you can enable workspace.

ADD show desktop icon to the launcher: This option is USED to display the desktop icon on the launcher.

Through behaviours tab you can make many changes on the appearance of desktop

Auto hide the launcher : You can use this option to reveal the launcher when moving the pointer to the defined hot spot.

Enable workspaces: By checking this option you can enable workspace.

Add show desktop icon to the launcher: This option is used to display the desktop icon on the launcher.

To append one FILE to another in Ubuntu LINUX you can use COMMAND cat file2 >> file 1. The OPERATOR >> APPENDS the output of the named file or creates the file if it is not created. While another command cat file 1 file 2 > file 3 appends two or more files to one.

To append one file to another in Ubuntu Linux you can use command cat file2 >> file 1. The operator >> appends the output of the named file or creates the file if it is not created. While another command cat file 1 file 2 > file 3 appends two or more files to one.

To color the Git console in UBUNTU you can use the COMMAND git config—global color.ui auto. In the command, the color.ui VARIABLE sets the DEFAULT VALUE for variable such as color.diff and color.grep.

To color the Git console in Ubuntu you can use the command git config—global color.ui auto. In the command, the color.ui variable sets the default value for variable such as color.diff and color.grep.

To CREATE LAUNCHERS on desktop in UBUNTU you can use

ALT+F2 then type “ gnome-desktop-item-edit –create-new~/desktop “, it will LAUNCH the old GUI dialog and create a launcher on your desktop.

To create launchers on desktop in Ubuntu you can use

ALT+F2 then type “ gnome-desktop-item-edit –create-new~/desktop “, it will launch the old GUI dialog and create a launcher on your desktop.

Libaio is Linux KERNEL Asynchronous I/O (A/O). A/O allows even a single application thread to overlap I/O OPERATIONS with other processing, by providing an interface for submitting one or more I/O requests in one system call without WAITING for completion. And a separate interface to reap completed I/O operations associated with a GIVEN completion group.

Libaio is Linux Kernel Asynchronous I/O (A/O). A/O allows even a single application thread to overlap I/O operations with other processing, by providing an interface for submitting one or more I/O requests in one system call without waiting for completion. And a separate interface to reap completed I/O operations associated with a given completion group.

You can open the BACKGROUND image in The Gimp (image editor) and then USE the dropper tool to SELECT the color on the specific POINT. It gives you the RGB value of the color at that point.

You can open the background image in The Gimp (image editor) and then use the dropper tool to select the color on the specific point. It gives you the RGB value of the color at that point.

By USING nohup. It will STOP the process receiving the NOHUP signal and THUS terminating it you log out of the program which was INVOKED with. & runs the process in the background.

By using nohup. It will stop the process receiving the NOHUP signal and thus terminating it you log out of the program which was invoked with. & runs the process in the background.

To UNINSTALL the libraries in Ubuntu, you can USE command sudo apt – GET REMOVE library_name

To uninstall the libraries in Ubuntu, you can use command sudo apt – get remove library_name

Export is a command in BASH shell language, when you try to SET a VARIABLE, it is visible or exported to any subprocess STARTED from that instance of bash. The variable will not exist in the sub-process WITHOUT the export command.

Export is a command in Bash shell language, when you try to set a variable, it is visible or exported to any subprocess started from that instance of bash. The variable will not exist in the sub-process without the export command.

To open Ubuntu terminal in a particular directory you can USE custom keyboard short CUT. To do that, in the COMMAND field of a new custom keyboard , type gnome – terminal – – working – directory = /path/to/dir.

To open Ubuntu terminal in a particular directory you can use custom keyboard short cut. To do that, in the command field of a new custom keyboard , type gnome – terminal – – working – directory = /path/to/dir.

To FIND a FILE in UBUNTU you have to use COMMAND,

• find .
• name “process.txt” .
• It will look for the current directory for a file called process.txt.

To find a file in Ubuntu you have to use command,

To enable curl on Ubuntu , first install libcurl, once DONE use FOLLOWING command SUDO/etc/init .d /apache2 RESTART or sudo service apache2 restart.

To enable curl on Ubuntu , first install libcurl, once done use following command sudo/etc/init .d /apache2 restart or sudo service apache2 restart.

To view the text FILE in Ubuntu, go to the specific folder where the text files are LOCATED by using the COMMAND cd and then type less filename.txt.

To view the text file in Ubuntu, go to the specific folder where the text files are located by using the command cd and then type less filename.txt.

To CREATE a FOLDER in UBUNTU, you have to USE COMMAND mkdir. It will be something like these : ~$ mkdir Ubuntu_rules.

To create a folder in Ubuntu, you have to use command mkdir. It will be something like these : ~$ mkdir Ubuntu_rules.

To access terminal , you have to go under APPLICATION MENU -> ACCESSORIES -> Terminal .
You can ALSO OPEN it with shortcut key Ctrl+Alt+T.

To access terminal , you have to go under Application Menu -> Accessories -> Terminal .
You can also open it with shortcut key Ctrl+Alt+T.

To reset the unity CONFIGURATION the simplest WAY to do is to hit OPEN a Terminal or hit Alt-F2 and run the command # unity –reset.

To reset the unity configuration the simplest way to do is to hit open a Terminal or hit Alt-F2 and run the command # unity –reset.

To enable STARTUP sound in Ubuntu:

1. Click control gear and then click on Startup Applications
2. In the Startup Application PREFERENCES window, click Add to add an entry
3. Then fill the information in COMMENT box like Name, COMMAND and Comment
4. /usr/bin/canberra-gtk-play—id= “desktop-login”—description= “play login sound”
5. Logout and then login once you are done

To enable startup sound in Ubuntu:

The COMMAND which enables root login is

#SUDO sh-c ‘ECHO “greater-show-manual-login=true” >>/etc/lightdm/lightdm.conf’.

The command which enables root login is

#sudo sh-c ‘echo “greater-show-manual-login=true” >>/etc/lightdm/lightdm.conf’.

When you use COMMAND /usr/lib/nux/unity_support_test-p it will GIVE detailed output about Unity’s requirements and if they are met, then your VIDEO card can RUN unity.

When you use command /usr/lib/nux/unity_support_test-p it will give detailed output about Unity’s requirements and if they are met, then your video card can run unity.

• In Ubuntu, Unity is the default windows manager. On left side of the Ubuntu it INTRODUCES the launcher and Dash to start PROGRAMS.
• In order to add new entries to the launcher you can CREATE a FILE name like .desktop and then DRAG file on the launcher.

• It does not support malicious e-mails and contents, and before any e-mail is opened by users it will go through many security checks
• UBUNTU uses Linux , which is a super secure O.S system
• Unlike other O.S, countless Linux users can see the code at any TIME and can fix the problem if there is any
• Generally, MALWARES and viruses are CODED to take advantage of WEAKNESS in Windows