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Linux Mint 12 ‘Lisa’ with Gnome Shell extensions called “MGSE”

November 5, 2011 Leave a comment
Linux Mint 12 ‘Lisa’ will come with its own customized desktop and it will be based on Gnome 3. The core desktop will be based on a series of Gnome Shell extensions called “MGSE” (Mint Gnome Shell Extensions) that will provide a layer on top of Gnome 3.


Take a look at the screenshot below:

The main features of MGSE are:

  • The bottom panel
  • The application menu
  • The window list
  • A task-centric desktop (i.e. you switch between windows, not applications)
  • Visible system tray icons
MGSE also includes additional extensions such as a media player indicator, and multiple enhancements to Gnome 3. Thus Linux Mint 12 will be more like a hybrid desktop balancing traditional desktop and new modern technologies.
Categories: tech Tags: , ,

How to use parted for creating patition larger that 2 TB

January 12, 2011 Leave a comment

To create partitions larger than 2TB we need to use GPT labels. Standard fdisk doesn’t understand GPT labels so we need to use parted.

Here we are going to partition the disk /dev/sdb

root@localhost ~> parted /dev/sdb

This will bring up parted.  Type help to view the commands in parted prompt.

(parted) help
check NUMBER                             do a simple check on the file system
cp [FROM-DEVICE] FROM-NUMBER TO-NUMBER   copy file system to another partition
help [COMMAND]                           prints general help, or help on COMMAND
mklabel,mktable LABEL-TYPE               create a new disklabel (partition table)
mkfs NUMBER FS-TYPE                      make a FS-TYPE file system on partititon NUMBER
mkpart PART-TYPE [FS-TYPE] START END     make a partition
mkpartfs PART-TYPE FS-TYPE START END     make a partition with a file system
move NUMBER START END                    move partition NUMBER
name NUMBER NAME                         name partition NUMBER as NAME
print [free|NUMBER|all]                  display the partition table, a partition, or all devices
quit                                     exit program
rescue START END                         rescue a lost partition near START and END
resize NUMBER START END                  resize partition NUMBER and its file system
rm NUMBER                                delete partition NUMBER
select DEVICE                            choose the device to edit
set NUMBER FLAG STATE                    change the FLAG on partition NUMBER
toggle [NUMBER [FLAG]]                   toggle the state of FLAG on partition NUMBER
unit UNIT                                set the default unit to UNIT
version                                  displays the current version of GNU Parted and copyright information

root@localhost ~> parted /dev/sdb
GNU Parted 1.8.1
Using /dev/sdb
Welcome to GNU Parted! Type ‘help’ to view a list of commands.
(parted)

To change the label to gpt we run the following command:

(parted) mklabel gpt

Next run the print command: This will list the disk geometry. Please note the size listed:

(parted) print

Model: Adaptec raid5-1 (scsi)
Disk /dev/sdb: 10.7TB
Sector size (logical/physical): 512B/512B
Partition Table: gpt

Number  Start   End     Size    File system  Name     Flags

This will tell us where to start and end the partitions. To create one huge partition ( 8 Tb = 8388608 bytes) run the following commands:

(parted) mkpart primary 0 8388607.000

The command reads as make a primary partition, start at 0 and end at 8388607.000

Also, if you are making a partition for a device smaller than the limit from the notes below, you can use the following if the geometry doesn’t show like it does above. Just exit out of parted, and run this from a shell:

root@localhost ~> parted -s — /dev/sdb  mkpart primary ext3 0 -1

This will take the whole disk for creating the partition.

The parition has been created and now you can quit parted:
(parted) quit

Now all that has to be done is to format the partition:(the -m swith tells mkfs to only reserve 1% of the blocks for the super block)

root@localhost ~> mkfs.ext3 -m1 /dev/sdb1
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
1024000000 inodes, 2047999751 blocks
20479997 blocks (1.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
62500 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848, 512000000, 550731776, 644972544, 1934917632

Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 38 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

Mount the disk

root@localhost ~> mount /dev/sdb1 /disk1

root@localhost ~> df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda3             240G  2.3G  225G   2% /
/dev/sda1             996M   45M  900M   5% /boot
tmpfs                 2.0G     0  2.0G   0% /dev/shm
/dev/sdb1             7.6T  177M  7.5T   1% /disk1

Now edit /etc/fstab to mount the partiton automatically on boot.

root@localhost ~>vi /etc/fstab

Add the following  line  in /etc/fstab

/dev/sdb1     /disk1   ext3    defaults        0 0

 

Categories: Linux, tech Tags:

How to make SSH work Faster?

January 12, 2011 Leave a comment

Here are some tricks to boost your pro­duc­tiv­i­ty when work­ing withSSH.

Au­to Lo­gin

OpenSSH has a great fea­ture “key-based au­tho­riza­tion” which us­es RSA/DSA key pair to do au­tho­riza­tion in­stead of pass­word. With the help of it, lo­gin can be done au­to­mat­i­cal­ly.

Here are the steps:

  1. Cre­ate ssh key pair, if you have’t one. Check ~/.ssh. If you find a fine with nameid_dsa.pub or id_rsa.pub, you are done since the key pair is ready to use. Oth­er­wise, cre­ate it sim­ply by typ­ing ssh-keygen and fol­low­ing the in­struc­tions. Keep in mind that there are two kinds of key pairs, RSA or DSA. I al­ways use RSA. You can choose one on your own. If you choose RSA with oth­er op­tions as de­fault, you will getid_rsa and id_rsa.pub in ~/.ssh. The for­mer file is the pri­vate key and lat­ter one is the pub­lic key.
  2. Make sure your ~/.ssh is pri­vate. I want to em­pha­size that here that the pri­vate key, i.e. id_rsa, is the equiv­a­lent with your pass­word since peo­ple who can ac­cess this file can lo­gin the re­mote ma­chine eas­i­ly as they got your pass­word! So make it pri­vate first.
    chmod 700 ~/.ssh
  3. Trans­fer your pub­lic key to the re­mote ma­chine which you want to lo­gin au­to­mat­i­cal­ly. SCP may be a pre­ferred way:
    scp ~/.ssh/id_rsa.pub user@remote.machine.com:~/my_key.pub
  4. Ap­pend your pub­lic key to the ~/.ssh/authorized_keys on the re­mote ma­chine.
    cat my_key.pub >> ~/.ssh/authorized_keys
  5. Done! Check whether you can lo­gin in­to the re­mote ma­chine au­to­mat­i­cal­ly by sim­ply type
    ssh user@remote.machine.com

    on your lo­cal ma­chine. If it works, re­move the pub­lic key on the re­mote ma­chine.

  6. For geek­ers who’d like to do it in one-line fash­ion, here it is:
    cat ~/.ssh/id_dsa.pub | ssh -l user remote.machine.com ‘cat >> ~/.ssh/authorized_keys’

Even Faster

Even au­to lo­gin is set up, in some cas­es you have to wait for sev­er­al sec­onds be­fore the shell prompt bombs out. Still frus­trat­ing, right? In some worse cas­es, you have wait more than 10 sec­onds or even longer! Why? Each time you con­nect a re­mote ma­chine, sshd would like to use your IP ad­dress to ap­ply re­verse DNS lookup to de­ter­mine your host­name. If the DNS serv­er goes slow, it may take sec­onds to re­turn the re­sults. The longer the lookup takes, the longer you have to wait.

Two tricks can be ap­plied to solve this prob­lem:

  1. Ed­it /etc/hosts on the re­mote ma­chine and add the IP ad­dress of your lo­cal ma­chine to it with an ap­pro­pri­ate host­name. So if you lo­gin the sys­tem, your IP ad­dress is re­solved lo­cal­ly, which is def­i­nite­ly faster.
  2. Dis­able DNS lookup on the re­mote ma­chine. Ed­it /etc/ssh/sshd_config and add one line:
    UseDNS no

    Restart the sshd serv­er then. If ev­ery­thing goes well, you will see the save of time.

Both tricks re­quire root priv­i­lege. If do not have root ac­cess, ask your ad­min­is­tra­tor to help you.

Trou­bleshoot­ing

Use ssh -v or ssh -vvv to out­put de­bug in­for­ma­tion and di­ag­nose the prob­lem.

Categories: Linux, tech Tags: ,

How ssh works

January 12, 2011 Leave a comment

Ssh works by the exchange and verification of information, using public and private keys, to identify hosts and users. It then provides encryption of subsequent communication, also by the use of public/private key cryptography.

SSH is designed to provide a secure method of authentication and data transport. This is accomplished via three main stages during the connection setup: SSH-TRANS, SSH-AUTH, and SSH-CONN.

As a user, you generate an “identity” on the client system by running the ssh-keygen program. This program creates a subdirectory $HOME/.ssh and inserts in it two files named identity and identity.pub which contain your private and public keys for your account on the client system. This latter file can then be appended to a file $HOME/.ssh/authorized_keys that should reside on any/all servers where you will make ssh connections.

As a system administrator, you generate a public and private key pair for the system itself. By use of this information contained within the system itself, the possibility of someone spoofing the system’s identity by faking IP addresses or munging up DNS records that associate IP addresses and domain names is removed. You would have to break into the system and steal its private key in order to sucessfully pretend to be that system. This is a big improvement in security.

Once you generate your public/private key on your local system you can place your public key in the authorized_keys of the server so you can bypass the login procedure and directly login into the server without the password.

When you ssh to a machine by the following command :

ssh -l admin -p 78 svrxx.domain.com

The first step performed is authentication of the server to the client and client to the server i.e first the server checks whether its publci key is contained in the file $HOME/.ssh/known_hosts this procedure is known as host validation if the key is present in the known_hosts file it will proceed with the subsequent authentication.

Else if it is not matching or not present will display the following message :

The authenticity of host ’svrxx.domain.com (67.75.52.50)’ can’t be established.
RSA key fingerprint is bd:e7:14:30:13:ba:74:77:47:b3:2a:b3:a1:07:2e:7a.
Are you sure you want to continue connecting (yes/no)?

Once you say yes then the public key of the server will be placed in the known_hosts file and you will not see this message again.

And once the host validation is complete the subsequent communcication will be encrypted using the private key that was generated from ssh-keygen command.

Will Unity an outstanding desktop option?

November 20, 2010 Leave a comment

In Ubuntu 11.04, Unity would become the default desktop interface. Ubuntu 11.04 will replace its GNOME interface with Unity, a totally new interface which you can experience now with Ubuntu 10.10 Netbook Edition.

“Orlando, Fla.–Mark Shuttleworth, founder of Ubuntu and the company behind it, Canonical, surprised the hundreds of Ubuntu programmers at the Ubuntu Developers Summit when he announced that in the next release of the popular Linux operating system, Ubuntu 11.04, Unity would become the default desktop interface”.

Unity is a new desktop environment designed for netbooks and touch-screen devices. It includes a new panel as well as a new vertical launcher.

Ubuntu Light is a version of Ubuntu designed to dual-boot with another operating system, and focused on getting on the web fast. Canonical is offering this  to computer manufacturers only, because it’s intended to be customized for specific computers in order to boot fast.

What is Unity?

Gnome comes with panels at the top and bottom of the display, but Unity comes with a top panel and a panel on the left side that can be utilized to launch apps as well as access already running apps.

“Unity and it’s range of technologies brings simplicity, power, and integration to both users and application developers. Unity puts design, integration, and Free Software at the heart of delivering a powerful and attractive experience”.

The experience will be different, depending upon your hardware.

Let’s see how this is installed and used:

If you are using Ubuntu 10.10 then installation instructions look like this:

1. Open up a terminal window.
2. Issue the command sudo add-apt-repository ppa:canonical-dx-team/une.
3. Issue the command sudo apt-get update && sudo apt-get install unity.
4. Close the terminal window.

If you are using 10.04, your instructions will look like this:

1. Open the Ubuntu Software Center.
2. Search for “netbook” (no quotes).
3. Mark ubuntu-netbook for installation.
4. Click Apply to install.
5. Accept any dependencies necessary.

Once the installation is completed you will then need to log out and choose the Unity session (or Ubuntu Netbook Edition – depending upon your release number) at the GDM login screen.

At first glance, you will feel like a normal netbook edition GNOME panel at the top of the screen. But, with a Google search box, it replaces the window list.  There’ s also a panel on the left with colourful stack of icons.

The Launcher:

The Unity application launcher is a dock. Selecting an icon in the launcher causes it to glow while the application loads. Dragging up and down scrolls the list of applications, and dragging an icon out allows it to be repositioned.

There are some default applications which always appear. Any application that is running will also appear, along with a small indicator that it is running on the left of the icon. The currently focused application also get a indicator on the right side.
Selecting an icon in the launcher causes it to glow while the application loads. Dragging up and down scrolls the list of applications, and dragging an icon out allows it to be repositioned. Right clicking on an icon initiates a scale effect which lets you select from all the windows for that application. There’s no support for minimizing windows.
It’s not easy to access applications which are not in the launcher because there’s no main menu. One item in the launcher is a folder which will show all the installed applications.

The window manager
Unity uses the Mutter window manager from GNOME 3. It’s a compositing window manager and supports some basic animations. At this time the integration between window title bars and the panel has not been implemented. The panel and launcher are run by Mutter, so it won’t be possible to use another window manager like Compiz with Unity. [update] A Compiz developer has Compiz working inside Unity, so this may not be true after all.

The panel

Clicking the Ubuntu logo scales all the windows and lets you select one to switch to it. The search box goes to Google for now, but later it should be used to search your computer. Everything else on the panel is an indicator, which the current exception of the network manager applet. Despite it’s appearance, the panel is not based on GNOME panel, but is drawn by Mutter.
I’m pretty excited about Unity. While the current version is not complete, it does seem to be in a usable state on my netbook so I’ll continue testing it there.

Though it is under many criticism from the ubuntu users.  Hopefully with Ubuntu 11.04, some things will be tweaked to make it look a whole lot better.

Categories: tech Tags: ,

GI completes merger of SoftLayer and The Planet

November 18, 2010 Leave a comment

Merger of two US-based hosting companies SoftLayer and The Planet has been completed, creating a strong competitor to the large hosting provider Rackspace.

The combined company, which will operate under the SoftLayer brand, will serve about 24,000 customers in 110 countries, operating 13 facilities in US and Europe that support about 76,000 servers, according to a GI news release. The company will provide dedicated and managed hosting, cloud-based services and colocation.

The brandname planet will get disappeared soon.

Planet, the word that will be written in history books.

Categories: tech Tags: ,

How to prevent your PEN drive from VIRUS

August 21, 2010 Leave a comment

You can protect your PC by just following the simple steps below .

* Connect your Pen Drive or USB drive to your computer .
* Now a dialogue window will popup asking you to choose among the options as shown in the figure.
Don’t choose any of them , Just simply click Cancel.
* Now go to Start–> Run and type cmd to open the Command Prompt window .
* Now go to My Computer and Check the Drive letter of your USB drive or Pen Drive . ( E.g. If it is written Kingston (I:) , then I: will be the drive letter .)
* In the Command Window ( cmd ) , type the drive letter: and Hit Enter.

* Now type dir/w/o/a/p and Hit Enter
* You will get a list of files . In the list , search if anyone of the following do exist
Autorun.inf
New Folder.exe
Bha.vbs
Iexplore.vbs
Info.exe
New_Folder.exe
Ravmon.exe
RVHost.exe or any other files with .exe Extension
* If you find any one of the files above , Run the command attrib -h -r -s -a *.* and Hit Enter.
* Now Delete each File using the following Command del filename ( E.g del autorun.inf ) .
* That’s it . Now just scan your USB drive with the anti virus you have to ensure that you made your Pen Drive free of Virus.

Categories: tech Tags: ,