-------- Forwarded Message -------- From: Varadarajan V nirvanar@gmail.com Reply-To: GNU/Linux Users Group, Mumbai, India linuxers@mm.glug-bom.org To: GNU/Linux Users Group, Mumbai, India linuxers@mm.glug-bom.org Subject: Re: [ILUG-BOM] changing boot.ini Date: Thu, 7 Dec 2006 11:56:00 +0100
On 12/6/06, BombayNews bombaynews@hotmail.com wrote:
Now after some boot files in XP got corrupted, the computer refused to boot.
Why would Ubuntu not boot if XP got corrupted? Are you sure Grub was the boot menu or was it the other way that XP loads grub to boot Ubuntu?
According to the engineer this is a usual problem with XP. He has advised editing boot.ini to make Linux the default OS but he warned that it can be done only once. Also that if Linux is made default Windows XP cannot be opened, etc.
I had a coulple of experiences in the past that for some reasons when I did a "grub-install" on my dual-boot machine with FC and XP, FC boot up but XP didnt. This was a problem with boot.ini file. I had to change the harddisk number in the boot.ini file and it worked. I am not that experienced with grub so I do not know what changes happened after I installed grub for the second time. May be someone on the list can explain that :-)
But what do u mean by XP files corrupted? Did you see any errors after you selected XP in grub menu? If there were errors from XP then Grub works fine and Ubuntu should boot.
what actually happened was when the computer was switched on, I got the message :
Boot from CD: Disk Boot Failure. Insert System Disk and Press Enter
The system was back to normal after the engineer restored some corrupted XP files with a backup CD. Why should this be so? I thought GRUB was independent of XP and corruption in XP files would not matter. But the engineer says XP is the primary system installed on the machine with Linux running on other partitions so corrupted XP would mean that the machine would not start at all.
This is how the boot.ini file reads. It is installed in the main partition as XP.
[boot loader] timeout=30 default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS [operating systems] multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /noexecute=optin
On 12/8/06, BombayNews bombaynews@hotmail.com wrote:
Boot from CD: Disk Boot Failure. Insert System Disk and Press Enter
If the system was boot up from Harddisk( you mentioned Boot from CD??) and you got this error that means MBR in your harddisk is corrupt be it GRUB or XP.
I thought GRUB was independent of XP and corruption in XP files would not matter.
Yes. GRUB is independent of XP. It works like this. The system is capable to read only the first sector of any bootable device. (Harddisk or CDROM or any other bootable device). This sector should contain the Master Boot Record(MBR). No MBR then "Non-System Disk". MBR has the information which partition contains Operating Systems. The first sector of any partition is called the Boot Sector. In windows only environment MBR points to the first sector of the partition where window$ is installed (c drive). This boot sector contains information to load the boot.ini file which contains the location of OS boot files of any window$ OS. This line in your file is [multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /noexecute=optin].
The case is different when GRUB is installed. It is installed on the MBR (also can be installed on the boot sector of any partition) and it has the ability to read and load the first sector of any partition. When you select XP in the grub boot menu it actually reads the refered boot sector and the boot sector has the code to load the boot.ini file. Note that XP has nothing to do with this behaviour of grub. XP comes into picture only after you select XP in grub boot menu. So if XP files are corrupted GRUB should still work fine provided you have not tried to fix XP by doing something with command "fixmbr" in Windows. If you run this command then window$ will overwrite the MBR in turn removing grub from MBR and makes your Linux unbootable. window$ cannot and does not want to detect your Ubuntu. Shame on them.
But the engineer says XP is the primary system installed on the machine with Linux running on other partitions so corrupted XP would mean that the machine would not start at all.
Thats not right if grub was the bootloader. Otherwise it should be that window$ boot Linux and got itself corrupted. Are you sure your engineer did not do anything other than restoring XP boot files? Can you still boot to Ubuntu? Is grub still your boot loader?
If I am getting carried away or if there is a simple explanation for this someone in the list please correct me. :-)
BombayNews wrote:
what actually happened was when the computer was switched on, I got the message :
Boot from CD: Disk Boot Failure. Insert System Disk and Press Enter
The system was back to normal after the engineer restored some corrupted XP files with a backup CD. Why should this be so? I thought GRUB was independent of XP and corruption in XP files would not matter. But the engineer says XP is the primary system installed on the machine with Linux running on other partitions so corrupted XP would mean that the machine would not start at all.
Could you explain what the engineer did to 'restore some' corrupted XP files with a backup CD? Did he do a re-install over the existing installation without a format? If so or even after a format and XP install, your grub would have been overwritten in the MBR and booting into linux would not be possible. If he tried sfc then the system would have returned to its original legal form with the 30 day activation key appearing.
"Boot from CD: Disk Boot Failure. Insert System Disk and Press Enter" indicates that your grub itself could have been corrupted.
Regards,
Rony. Send instant messages to your online friends http://uk.messenger.yahoo.com
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BombayNews -
Rony -
Varadarajan V