Linux (Fedora) and sata Drives 

I have sata drives on my system, or a combination of IDE and sata drives. Do I need to know anything special?

These drives are not jumpered like IDE (pata) drives, but seen by the bios on the physical channel they are on, or in the order where they are connected on the motherboard connector. There is no primary master, slave or other designation.

If you have only a single sata drive on your system, it will be seen by Linux as physical drive sda, not hda like IDE (pata) drives.

If you have multiple sata drives, they will be names in the order that they are connected to the motherboard connectors. If connected to the first sata connector on the motherboard, it will be seen as sda, if the second connector sdb, and so on.

If you have a combination of sata and IDE drives on your system, the boot order of the drives is dependent on which drive is set in the bios as the boot drive. It can be either, depending on the bios settings.

If you bought a sata system that came pre-installed with a sata drive, then that drive is the boot drive. Adding an IDE drive is no problem, but their ide drive will now be the boot drive, unless you set it as such in the bios. Fedora will see the correct drive set in the bios,  as the boot drive.

Folks who install Fedora often run into problem when they attempt to install Fedora on a second pata drive on a sata system, as they are often worried about upsetting there sata drive, or installation of Windows on the sata drive.  Worse yet, they may remove the sata drive to make sure that they don't accidentally overwrite the sata drive with Windows pre-installed. If the bios only sees an IDE drive on the system, it defaults to that drive as the boot drive. Reconnecting the sata drive after the Fedora installation makes the sata drive the boot drive again. No grub and no Fedora on boot, as you have now defaulted back to the sata drive as primary drive on the system. 


Grub and sata:

I removed my boot sata/pata drive to install Fedora, so that I would not upset my windows installation. I put the drive back in and now I only can boot into Windows. Grub is gone!

Not really. Folks who install Fedora often run into problem when they attempt to install Fedora on a second pata drive on a sata system, as they are often worried about upsetting there sata drive, or installation of Windows on the sata drive.  Worse yet, they may remove the sata drive to make sure that they don't accidentally overwrite the sata drive with Windows pre-installed. If the bios only sees an IDE drive on the system, it defaults to that drive as the boot drive. Reconnecting the sata drive after the Fedora installation makes the sata drive the boot drive again. No grub and no Fedora on boot, as you have now defaulted back to the sata drive as primary drive on the system.


I think that I understand this, but now I must change the drive order in the bios to make Fedora boot, or Fedora does not boot, or grub gives me an error message. There is no option to dual boot Windows.

That is correct. You have made a physical change on the drives in the system. By putting the Windows drive back in the system, it is now the boot drive, as set in the bios. The Master Boot Record (MBR) for Windows is still on the untouched sata drive, so Windows boots fine. The Grub bootloader is still on the other drive, which is no longer the boot drive.

If you change the boot drive order in the bios back to the Fedora drive, it usually boots, as it is now the boot drive, with Grub on the MBR of that drive. Remember, you took the windows drive out to install Fedora, so Fedora has no way to know that you originally had Windows installed on a drive, as it was not physically present during the installation process. Consequently, no Windows installation was detected to make grub configure itself to boot Windows as an option.


How do I fix this?

Well, the first fix would have been to install Fedora on your second drive, without changing the boot order in the bios at any point on the process.  All the hard drives should remain in the system, as you want them, with the boot order in the bios set as it was originally configured. The trick here is making sure that Fedora saw the drives correctly during the installation process and you assured that the grub bootloader was installed to the MBR of your boot drive.  See Making sure that Grub Installs Correctly (Dual Hard Drive Scenario).

If you have already done the deed, well, then it's a little more complicated. You can;

(1) re-install Fedora with all the drives in the system, making sure that you follow the guide "Making sure that Grub Installs Correctly", or;

(2) dive into the grub world, by reading Recovering Grub when you make a Mistake - Fedora on a second hard drive in the system.

You can also edit Grub temporarily at the Fedora boot splash screen. This is a neat tool that allows you to test your changes, before adding them to the grub.conf file and make them permanent. But, this is a subject of a future article.