Daily Archives: April 23, 2012

installing XP after windows 7

 

 How many times you faced with a customer who need to install windows XP to his desktop after you finished installing windows 7 and loaded all the drivers and soft wares ?

Moving from a lower version of operating system to a higher version and mutli booting was always an  easier task because your newer operating system will always recognize and set the required parameters to co exist with the older one.

Back in the time of introduction of windows XP customer has the issue of mutlibooting between windows 98 and windows XP . But at that time the concept was relatively easy because windows 98 does not have a boot manager and windows XP has a boot manager .

But if  both of your operating system has a boot management system and if that boot management systems are not ready to co-operate with each other , then it is going to be nightmare for the IT team.

 

So the question is

Can you install windows XP after installing Windows 7 or Vista

It is always better that you plan the installation before hand and avoid such a situation . But if you are trapped in such a situation , read on and do as we mentioned and things are going to be fine.

Scenario :

You have two partition on your machine . C drive is the active partition in which you installed windows 7  and it was working fine . Then you installed windows XP by booting from XP boot CD and installed XP to the D drive . After XP installation is over , the only OS that is showing up is XP and yes you can still access your windows 7 drive and data but you can not bring up the OS

may be you have  tried to repair your windows 7 by booting up from the 7 DVD and now only 7 is showing up and you badly need a situation in which both of the operating systems are functional . Right ?

 Why this happens (to me) ?

from the early days of windows NT family of operating systems , Microsoft follows  a common structure for the boot management based on NT loader , boot.ini and bootsect.com . All those concepts were changed in windows Vista/7 /2008 series of operating system with BCD boot and bootmgr. We are not going to granular details but lot of things changed that made it difficult for windows XP  to understand how the windows 7 is handling the booting process of your system and it will destroy the structure created by 7 and follow its own procedure .

 

Solution  :

 

we are assuming you installed windows XP after windows  7 and now only XP boots up. After you reach the desktop of XP , insert the windows 7 DVD to the optical drive.

Go to command prompt by typing CMD at the run option and go to the drive letter of your optical drive. we are assuming it as E:  

now move to the folder named boot by typing cd boot  , and type the following command

    bootsect.exe /nt60 all

 

 

 

 

Now the boot sector for windows 7 is fixed . Reboot and you can see that machine will boot to windows 7. Now our aim is to create a multi boot environment where windows 7 and windows XP can co exist.

To achieve it  you have to edit the boot sector with BCDEdit option  . There are so many thirdparty software available to do this task  but you follow the official way from Microsoft.

We assume you  now booted up your windows 7 and it is working fine. Now  start your command prompt with administrative privileges  . For that  go to

 

All programs –> Accessories –> right click on command prompt and select run as Administrator 

 

 

From the command prompt run the follwing command in the specified order

bcdedit  / create  {ntldr} /d  ” Microsoft Windows XP “

bcdedit  /set  {ntldr}  device partition =C:

bcdedit  /set  {ntldr} path  \ ntldr

bcdedit  /displayorder  {ntldr} /addlast

Please refer to the screen shot for clarification of the commands

Now exit the command prompt and reboot your windows 7 , Now your system will show dual boot option between windows 7 and XP.

Hope you find it useful . Give us feedback about this post by commenting here and liking our Facebook Page .

 

DAS, NAS and SAN

 

 

So many Acronyms , and people find it really hard to memorize all these computing industry acronyms or alphabet soups as some one said. Anyway  here we are going to discuss about three alphabet soups that is normally confusing a typical infrastructure professional  when it comes to the storage solutions .

 

 

As far as the data storage is concerned , hard disk is the primary online storage solution from the early days of  computing . Here we are discussing three terminologies associated  with hard disk data storage .

 

DAS   – Direct attached storage

The normal method of data storage used by your typical machine . The hard disk is attached too your machine by means of a direct connector on your mother board or through additional add on cards. We are using normal IDE , Serial ATA or SCSI technologies for interfacing the hard disk .  The kind of data transfer on these systems is known as Block level data transfer.

We are using DAS for a normal desktop systems and entry level servers because it is cheaper to implement and maintain . But this technology limit the data storage to individual machines and any issue with the local system will affect the data on the system also .

 

NAS  – Network attached storage

 

this concept is different from DAS because your data storage  is located on the network. Even though NAS devices are available as a stand alone box that connects to the network , they are just  customized machines loaded with file services like NFS or CIFS . ie if you are accessing a file server over the network and using the network share , it can be considered as a NAS.

If a company is using a dedicated NAS devices as shown above , it means that these devices contain an embedded  stripped down OS and equipped with a RAID controller for improved hard disk performance and multiple network cards for fault tolerance  . You can also use a regular  computer loaded with operating systems like Free NAS for achieving similar  result.

NAS  is using file level data transfer compared to the block level data transfer in DAS . The issue with the NAS devices is that you can not make NAS as your prime data storgae device as you need to boot from a local harddisk to access the NAS. So you need a DAS , boot to the local OS and then access NAS. so NAS will be best suited in situations where you need a central storage repository for your Data.

 

 SAN – Storage Area Networks 

 

So what if you need the functionality of the DAS  like block level transfer and  boot from the hard disk option and still need the flexibility and security of a NAS , then your trivial option will be a SAN.

 

a SAN  is  also a dedicated computing equipment loaded  with   many hard disk and RAID functionality but the main difference from SAN is that it attached to the  system using the SCSI commands itself using a dedicated connectivity system known as fiber channel . ie you are plugging in FC cards to your system which in turn connect  to your SAN box using optical fiber cables

 

It support multiple  computers to attach to a single storage and permitting access to the data at block level.  SAN is the ultimate choice of data centers and high end computing environments as it permits multiple computers to access a single hard disk and support  features like clustering and v motion.