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Showing posts from 2012

UnlockRoot - An easy to use tool for rooting android devices

UnlockRootis an easy to use android rooting application on windows. Android rooting is the process of allowing users of smart phonestablets, and other devices running the Android mobile operating system to gain "root access" within Android's subsystem. UnlockRoot supports numerous number of android devices. UnlockRoot is regularly updated to support newer android devices. UnlockRoot can be downloaded from here.

How to cut/convert your miniSIM to MicroSIM or nano SIM?

We can convert our mini SIM cards to micro or nano SIM with the easy steps published at : http://www.airportal.de/nanosim/ . The web page has a simple PDF template which has instructions how to cut the SIM card into different shapes. the PDF template can be downloaded from here too. 
Note : All copyrights are owned by respective owners. for more details refer to : This is  released by Christian von der Ropp under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License (CC BY-NC-SA 3.0) http://creativecommons.org/licenses/by-nc-sa/3.0/

Fedora Live USB Creator

The fedora liveusb-creator is a tool for easily installing live operating systems on to USB flash drives. This tool helps you to install the fedora linux on USB disk. The tool can be downloaded from here.

What is the difference between 802.11a/b/g/n wireless specifications ?

Here is the major difference in the form of simple chart :

802.11a802.11b802.11g802.11n
Operating Frequency5.15Ghz - 5.35Ghz2.4Ghz2.4Ghz2.4Ghz or 5GhzBandwidthUpto 54Mbps(actual 22Mbps)Upto 11 MbpsUpto 54 MbpsUpto 700MbpsRange50 feet100 feet100 feet50 FeetCostMore expensiveLess expensiveLess expensiveMore expensiveInterferenceLess proneMore proneMore proneprone

How to backup and restore GPT header and table / MBR on mac ?

Mac OS X systems use GPT based partition table on a physical hard disk. Sometimes due to disk errors or any other reasons the GPT partition table may get corrupt. In such situations the operating systems restore the GPT table from the secondary GPT header lying at the end of the disk. There are some situations when secondary header is also corrupt then it is very hard to recover the partition schema of that disk. We can take a backup of the GPT table from the mac in the form a device file and can use it to restore back onto disk. 
The GPT table and header of the disk can be backed-up as below :
         $ sudo dd if=/dev/disk0 of=GPT bs=512 count=34
The GPT table and header of the disk can be restored as below :
$ sudo dd if=GPT of=/dev/disk0 bs=512 count=34


Similarly for MBR disks back up can be taken as below:
         $ dd if=/dev/disk0 of=MBR bs=512 count=1

MBR header can be restored back as :
$ dd if=MBR of=/dev/disk0

How to remove firmware password prompt on mac if password is forgotten ?

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We might end up  in a problem where we forgot the password which we have kept for firmware on mac.  We might see following screen when mac powers on, without leaving any option to reset the password using the DVD or any other mac os x installer disks.
We  can remove this firmware password  prompt by resetting the NVRAM, by following below specified steps: Change the memory configuration of your mac either by removing one of the RAM's or by adding another RAM to existing setup.Turn on the mac, Immediately hold command + option + P + R keys on your mac keyboardPerform NVRAM reset  for 3 times (here you will hear mac chiming for 3 times )Release the command + option + P + R keys.  This should have removed the firmware password prompt.


What is "whatis" and "locate" databases in mac os x? How to Build or Rebuild them ?

On the Mac OS X, Terminal app users can use whatis and locate commands to improve their search experience in the terminal similar to Spotlight. 
whatis :           whatis command gives us the short description about the system commands. To display short description whatis uses its "whatis" database. whatis database is set of database files containing short descriptions of system commands which are commonly used in command line , such as in Terminal app. Mac OS X periodically updates the whatis database on a weekly bases if enabled in periodic.conf file. If whatis database is not built then we can build it with following command       $ sudo /usr/libexec/makewhatis
      or 
sudo periodic weekly
When we run the whatis command, the output will be as :
      $ whatis system_profiler       system_profiler(8)       - reports system hardware and software configuration
Locate :
The locate command provides help in finding or tracking  down every instance of a file, filetype, app, exte…

How to use NFS over TCP and UDP

NFS can be exported over TCP or UDP. Default transport protocol for NFSv4 is TCP. Whenever we mount the NFS as below, the connection gets established over TCP. If we want to mount NFS over UDP then we have to use -o udp switch as explained below.
NFS over TCP:
mount -t nfs  //[ip-address or hostname]:/mynfs-share /mnt
NFS over UDP:
mount -t nfs -o udp //[ip-address or hostname]:/mynfs-share /mnt

How to check S.M.A.R.T status of your harddisk for disk health

S.M.A.R.T. (Self-Monitoring, Analysis and Reporting Technology; often written as SMART) is a monitoring system for computerhard disk drives to detect and report on various indicators of reliability, in the hope of anticipating failures. 
On Mac OS X : The following command will report the SMART status on Mac OS X 
$diskutil info disk0 | grep SMART
The output will look like some thing below :
SMART Status:             Verified 
If the output says "Failing" or "About to Fail", other than "Verified" then you might need to backup data and try repairing the disk or replacing the disk.

On Linux :
smartctl -d ata -H /dev/sdb
This command will run overall-health self-assessment test on your hard disk and prints a report of disk test results.