Re-install Windows and leave Fedora intact

[Lukast]

Hi,

I would like to ask those with more experiences when re-installing M$ Vista crap.I do not want to reinstall my working Fedora 11. Do I have to backup my linux partitions?

How do I resurrect my linux bootloader then? With safe mode with Fedora DVD, right?

Are there any differences between Windows 7 dual boot with Fedora 11?

I have these partitions:

/dev/sda1               1        9614    77222880    7  HPFS/NTFS
/dev/sda2           18450       19457     8088576    7  HPFS/NTFS
/dev/sda3   *        9614        9640      204800   83  Linux
/dev/sda4            9641       18449    70758292+   5  Extended
/dev/sda5            9641       18449    70757376   8e  Linux LVM

[JohnVV]

a question

/dev/sda1 1 9614 77222880 7 HPFS/NTFS
/dev/sda2 18450 19457 8088576 7 HPFS/NTFS

you have MS Windows partitions at the front AND end of the drive . Why ?

that could cause problems for the windows installer also the MBR is not bootable this also might cause a problem . The windows dvd might not be able to reinstall with out giving an error .

[Lukast]

There is "recovery" partition. I have HP laptop and they do not ship installation medias of your OS but give you this recovery partition.

[stoat]

... also the MBR is not bootable this also might cause a problem .

Hello JohnVV and Lukast,

I don't think you meant to say "MBR" which, as you know, is the very first sector of every partitioned hard drive and does not appear in an fdisk report. The first partition in the fdisk report is 62 sectors away from the master boot record. But I can explain why the Windows partition is not the active partition in Lukast's fdisk report. It's because of Fedora 11. Prior to Fedora 11, Anaconda would leave the active partition alone. Not any more. Anaconda will now change the active partition to the Fedora boot partition. But I don't really know why since Fedora (and all GRUB-booted Linuxes) do not use the active state of partitions for booting. GRUB boots in stages that each already know (or can find) where the next stage is located. Only Windows relies on the active partition for its boot loader files. But I'm confident that the developers had some reason behind that new behavior in Anaconda. It doesn't really matter though since it does no harm even if there isn't a good reason for it.

Anyway, when Vista is re-installed, its installer will know to make the partition with Vista's boot loader files active so Vista can boot directly from BIOS. Which brings me to this...

How do I resurrect my linux bootloader then? With safe mode with Fedora DVD, right?

That's right. After re-installing Vista, it will boot directly from BIOS, and Fedora will not boot until you either re-install GRUB or configure Vista to boot Fedora. IMO, re-installing GRUB is surely in the top ten most heavily documented topics here. But if you need help re-installing Fedora's GRUB after re-installing Vista, then return here for help with that. I'm sure it will come from every direction.

[JEO]

"Anaconda will now change the active partition to the Fedora boot partition. But I don't really know why since Fedora (and all GRUB-booted Linuxes) do not use the active state of partitions for booting. GRUB boots in stages that each already know (or can find) where the next stage is located. Only Windows relies on the active partition for its boot loader files. But I'm confident that the developers had some reason behind that new behavior in Anaconda. It doesn't really matter though since it does no harm even if there isn't a good reason for it."

Hi stoat,
Many BIOSes will not try to boot a drive even if it has grub in the MBR if they detect that no partitions on the drive are set active (parted boot flag on). This has bitten me many times on several systems. One partition on a bootable drive should be set active. For grub in the MBR, any one primary partiton set active will allow it to boot.

[stoat]

Many BIOSes will not try to boot a drive even if it has grub in the MBR if they detect that no partitions on the drive are set active (parted boot flag on). This has bitten me many times on several systems. One partition on a bootable drive should be set active. For grub in the MBR, any one primary partiton set active will allow it to boot.

Thanks. That's a good explanation for it. After all, we've gotta figure that it often happens that a drive is completely repartitioned and only Fedora is installed. In that situation and with the issue you mentioned, it could make a difference.

I just thought of something related to this. I use NTLoader to boot XP, Fedora 10, and Fedora 11 on my desktop. When I installed Fedora 11, I chose to install GRUB in the first sector of the Fedora 11 boot partition like I always do. Anaconda did not change the active partition because NTLoader never stopped working. So I guess I can conclude that the active partition is changed to the Fedora 11 boot partition when GRUB is installed in the master boot record and not when it is installed in the Fedora boot partition.

It's still a new development with Fedora 11. I just did some searching for threads with Fedora 10 fdisk reports that also involved Windows, and the Windows partitions always stayed the active partition.

UPDATE: I'm now not so sure about this...

So I guess I can conclude that the active partition is changed to the Fedora 11 boot partition when GRUB is installed in the master boot record and not when it is installed in the Fedora boot partition.

A day or so ago I installed Fedora 11 on my Thinkpad with XP, Fedora 10, Debian, and Ubuntu. It replaced Fedora 10. I use the XP boot loader to boot everything. As usual, I chose to install GRUB in the first sector of the Fedora 11 boot partition. When I rebooted, Fedora 11 booted directly. Anaconda had changed the active partition to the Fedora 11 boot partition, and the MS boot code in the master boot record was booting it. It was easy to fix by changing the active partition back to XP (probably the explanation for my forgetting about it from the time before). Until I learn otherwise, I now am of the belief that Fedora 11's Anaconda always changes the active partition. I'm not interested enough to do a bunch of installs to find out with certainty. Besides, it doesn't really matter unless you're using NTLoader like I do.

ANOTHER UPDATE: Okay now it's clear what happened in my two cases. The reason installing Fedora 11 did not bust the Windows boot loader of my desktop is because Fedora 11 was installed on a different hard drive. Anaconda changed the active partition of that drive, but it didn't matter to NTLoader because it was safely located on the first hard drive. And when I installed Fedora 11 on my Thinkpad which has only one hard drive, NTLoader was busted by installing Fedora 11. It was repaired by changing the active partition back to the XP partition. So the final conclusion is that Fedora 11's Anaconda always changes the active partition.

[stoat]

My apologies for the diversion, Lukast. Some of your other questions in the first post...

Do I have to backup my linux partitions?

I always make thorough tested backups to an alternate medium any time I install a new operating system. OS installers have great destructive potential because they can reformat entire partitions.

Are there any differences between Windows 7 dual boot with Fedora 11?

I don't think so. Vista and Windows 7 boot the same way. Actually, from Fedora's viewpoint of them, all MS system are handled the same way: load and execute the boot sector code of the partition with their boot loader files.

[HansdeGoede]

Hi,

Good news, further evaluation of this issue has lead to the conclusion that
the removal of the active flag from an existing partition indeed is unwanted
behavior.

So I've just changed this, and for F-13 we will no longer do that, see:
http://git.fedorahosted.org/git/?p=a...118ad9faf24cc9

Regards,

Hans

[JEO]

Thats great news, thanks!