Jun 14, 2010

Nokia First Dual Sim in india

Nokia has released their first Dual SIM phone C2  and C1-100

Nokia C1-100                      


By simply holding down a key, people are able to switch between SIM cards, meaning that they can take advantage of reduced call rates, flexibility when traveling from one country to another, or being able to share a phone within a family and still use their own SIM card. This is a great added convenience feature, considering the low price of the phone.”

The model C1 is a dual SIM handset, but only one SIM will work at a time. Simultaneous operation is not possible. You have to switch between the SIM cards for usage. The only advantage is that no physical SIM change is required.
C1-100 is a Series 30 device, comes with a s/by battery backup of 6 weeks, 500 phonebook entries and the standard features like FM Radio with 3.5 mm jack. The model will be available in blue, red, light grey and green colours , expected to be available by third quarter of 2010.

 This handset is proposed to be available by the third quarter of 2010 at a price, a little over Rs 2090

Nokia C2                           

Nokia C2 is the advanced version of C1. Same as of standard Dual SIM handsets Nokia C2  offers the simultaneous usage of two SIM cards, means the incoming calls and text messages can be received to either number while the phone is on.  The unique feature in this Dual SIM handset is the “hot –swappable” SIM card feature- This facilitates  removal and insertion of SIM card when the phone is on.
C2 is a Series 40 device . The other features include 1000 entries phone book, 16.5 days long standby time, Bluetooth, GPRS and VGA camera, FM radio, Music player, Micro SD expandable upto 32 GB.

Nokia C2  is expected to be available in market  by the last quarter of this year and it will cost around 35 to 39 Euros  (Rs 1,998-Rs 2,215) excluding the taxes.


Feb 8, 2010

Tcs Website hacked

 Tata Consultancy Services Ltd. (TCS) has witnessed the hijacking of its official website The hackers not only attacked the website but also allegedly changed its domain name  and put it up for sale

The homepage says:

    This domaine name is for sale. Please contact us for further information.

    Ce nom de domaine est a vendre
    Merci de nous contacter pour obtenir de plus amples informations.

The screen-shot of the website, accessed from India, at 2:30PM today, is shown above. It is rumored that, the hackers have made changes to the DNS settings of the website. They have put up a widget displaying current traffic on the homepage!

Oct 17, 2009

How To Create Linux LVM in linux

What’s LVM? Why using Linux Logical Volume Manager or LVM?

These questions are not the scope here. But in brief, the most attractive feature of Logical Volume Manager is to make disk management easier in Linux! Basically, LVM allows users to dynamically extend or shrink Linux “partition” or file system in online mode! The LVM can resize volume groups (VG) online by adding new physical volumes (PV) or rejecting those existing PVs attached to VG.

let’s assume that
  • The LVM is not currently configured or in used. Having say that, this is the LVM tutorial if you’re going to setup LVM from the ground up on a production Linux server with a new SATA / SCSI hard disk.
  • Without a luxury server hardware, I tested this LVM tutorial on PC with the secondary hard disk dedicated for LVM setup. So, the Linux dev file of secondary IDE hard disk will be /dev/hdb (or /dev/sdb for SCSI hard disk).
  • This guide is fully tested in Red Hat Enterprise Linux 4 with Logical Volume Manager 2 (LVM2) run-time environment (LVM version 2.00.31 2004-12-12, Library version 1.00.19-ioctl 2004-07-03, Driver version 4.1.0)!

How to setup Linux LVM in 3 minutes at command line?
  1. Login with root user ID and try to avoid using sudo command for simplicity reason.
  2. Using the whole secondary hard disk for LVM partition:
    fdisk /dev/hdb

    At the Linux fdisk command prompt,
    1. press n to create a new disk partition,
    2. press p to create a primary disk partition,
    3. press 1 to denote it as 1st disk partition,
    4. press ENTER twice to accept the default of 1st and last cylinder – to convert the whole secondary hard disk to a single disk partition,
    5. press t (will automatically select the only partition – partition 1) to change the default Linux partition type (0×83) to LVM partition type (0×8e),
    6. press L to list all the currently supported partition type,
    7. press 8e (as per the L listing) to change partition 1 to 8e, i.e. Linux LVM partition type,
    8. press p to display the secondary hard disk partition setup. Please take note that the first partition is denoted as /dev/hdb1 in Linux,
    9. press w to write the partition table and exit fdisk upon completion.

  3. Next, this LVM command will create a LVM physical volume (PV) on a regular hard disk or partition:
    pvcreate /dev/hdb1
  4. Now, another LVM command to create a LVM volume group (VG) called vg0 with a physical extent size (PE size) of 16MB:
    vgcreate -s 16M vg0 /dev/hdb1

    Be properly planning ahead of PE size before creating a volume group with vgcreate -s option!
  5. Create a 400MB logical volume (LV) called lvol0 on volume group vg0:
    lvcreate -L 400M -n lvol0 vg0

    This lvcreate command will create a softlink /dev/vg0/lvol0 point to a correspondence block device file called /dev/mapper/vg0-lvol0.
  6. The Linux LVM setup is almost done. Now is the time to format logical volume lvol0 to create a Red Hat Linux supported file system, i.e. EXT3 file system, with 1% reserved block count:
    mkfs -t ext3 -m 1 -v /dev/vg0/lvol0
  7. Create a mount point before mounting the new EXT3 file system:
    mkdir /mnt/vfs
  8. The last step of this LVM tutorial – mount the new EXT3 file system created on logical volume lvol0 of LVM to /mnt/vfs mount point:
    mount -t ext3 /dev/vg0/lvol0 /mnt/vfs

To confirm the LVM setup has been completed successfully, the df -h command should display these similar message:

/dev/mapper/vg0-lvol0 388M 11M 374M 3% /mnt/vfs

Some of the useful LVM commands reference:
vgdisplay vg0
To check or display volume group setting, such as physical size (PE Size), volume group name (VG name), maximum logical volumes (Max LV), maximum physical volume (Max PV), etc.
To check or list all physical volumes (PV) created for volume group (VG) in the current system.
To dynamically adding more physical volume (PV), i.e. through new hard disk or disk partition, to an existing volume group (VG) in online mode. You’ll have to manually execute vgextend after pvcreate command that create LVM physical volume (PV).

Sep 19, 2009

How to add route in Linux

To view the current routing table run “route -n

[root@klmppswdr01p ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface U 0 0 0 eth0 UG 0 0 0 eth0 U 0 0 0 eth0 UG 0 0 0 eth0

To add a route refer to the command below.

"route add -net netmask gw"

To delete a route refer to the command below.

"route del -net netmask gw"

The routing information above is not persistent across reboots. After a reboot, the routing information will be lost and you need to add them in again.

The routing information above is not persistent across reboots. After a reboot, the routing information will be lost and you need to add them in again.

To make the routing information persistent, add the “route add” line as seen above into the /etc/rc.local file.

Sample /etc/rc.local file.

# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.
touch /var/lock/subsys/local
route add -net netmask gw

Sep 11, 2009

Linux File Structure

For those of you coming from windows backgrounds, the way the linux filesystem is laid out may seem confusing at first glance…. but that is where this article comes in !

The first thing you should know when working with linux, is that everything is treated as either a file or directory. Yeap thats right, even hardware is considered a file by linux, and, speaking of hardware… all your hardware devices are located in the /dev directory, but more on that later.

Another thing that confuses windows users, is the fact that linux dosen’t use drive letters to distinguish between different partitions and devices. that is to say in linux, the “root” of your filesystem is / whereas in windows it would most probably be C:\ . Drives in linux are “mounted” to directories where their data can then be accessed, so for instance, if you needed to use your thumbdrive, you would plug it into your computer, and then mount it using the “mount” command, which specifies the path to the device ( something like /dev/sdb or /dev/sdc ) and the directory to mount it to (usually /mnt or /media), then you can happily access your drive from the /mnt or /media folder.

Sounds strange right? well yes it does if you come from a windows environment, where the entire operating system is consolidated onto a single drive. However, with linux and the ability to mount devices as directories, it gives the end user much greater flexibility in splitting up their operating system over several drives or partitions.

to understand what I mean when I say that this approach in mounting drives grants flexibility, I must first explain the different folders in linux and what they store

The graphic above shows the linux filesystem hierarchy, now will explain in a bit more detail what each folder contains.

/ this is the root folder, all other folders come under root.. think of it as C:\ in a Windows context.

/bin this folder contains all the user-essential binaries (programs) that are needed to administer and run your linux system… delete this folder and your system is broken.

/boot as the name suggests, this folder contains configuration files and other necessary files that are needed by the bootloader

/dev this folder contains device files (remember, these files represent physical devices, so be careful when working with them)

/etc this folder contains all the configuration files used by the system, you can also start and stop services (daemons ) from here

/home this folder contains the home folders of all the normal (non – root ) users on the system .. think of it as my documents in windows

/lib this folder contains software libraries

/media this is a mount point for removable devices… this is where you would usually mount your thumbdrives … etc

/mnt this is a temporary mount point

/opt this folder contains add on software (extra software)

/sbin this folder contains binaries that can only be run as the root user (”superuser”)

/tmp this folder contains temporary files that are erased upon reboot

/usr this folder and its subfolders contains user installed programs and utilities and libraries

/var this folder contains files that change alot (”Variable files”)

/root this folder contians the root user’s files

/proc this is a psuedo folder, that contains information about the linux kernel and hardware that is updated in realtime.

Now back to how mounting grants flexibility…

you see how the different folders all contain parts of the operating system? well we can actually mount a seperate hard drive for each of this folders. for example, your /home folder can be put on another harddrive than your / which means that you can easily recover your personal files if the harddrive on / fails because the harddrive mounted to your /home folder is seperate from the one that is mounted to your /

So there you have it, you now know a little bit more about the nuts and bolts of linux based operating systems.