Suse and multiple hard drive issues.

azith28

Hi,

I'm trying to set up a custom suse linux system to boot off one drive, a western digital and let me mount the second drive, a Seagate as /dev/sdb . For some reason, everything i do with the system is trying to boot the seagate as /dev/sda. I've excluded the Seagate from the boot order in CMOS, I've deleted all the partitions on the Seagate, I've done a dd write over the drive to erase the boot sectors, tried switching the SATA cables, and nothing I do is changing the situation. The only way i was able to get the WD to boot as the main drive was to change the FStab on the WD's OS to identify it as /dev/sdb. It's like it is booting from the WD's boot sectors, but the WD's boot table is mounting the ST first for some reason.

Any ideas why this is happening?

Thanks

Nija

Dumb question, is the Seagate's jumper set to Master/Primary?

azith28

No jumpers on it. Its a Seagate ST500DM002 model

bowen

Whatever drive your MBR is on (the first drive) is still identifying this drive as the place to boot.

You'll need to change grub/fstab to fix it.

azith28

Okay, but like i mentioned, i did that to get it to boot to the right drive, but now that ive got it up, how do i now fix it so that sda is the OS drive?

bowen

The issue I'm thinking is this drives needs a bootloader installed on it, and to be made bootable.

Which probably means you'll need a fresh install.

SDA/SDB is mostly because that's what the OS decided to name the drive.

What you need to do is unplug the seagate, move the other drive to the 1st port on the motherboard (they're labeled, sometimes they start at 0, sometimes at 1). Once you've gone through and reinstalled your OS (you really should just do this, don't try to fuck around with moving drives and "fixing it"), plug in the seagate to the 2nd port, and set up your fstab and mountpoints.

Nija

This is my old school thinking (and may not be appropriate for SUSE), but when installing the OS, only have one drive plugged in. After you have everything installed and working, you can shutdown, install the new drive and format it the way you want. The OS should recognize the second drive as sdb from that point on.

bowen

Yeah linux is kind of a bear about this kind of shit.

Once it maps out serial numbers, you're kind of fucked no matter how you organize them physically and in BIOS. Kernel loads itself, identifies devices maps the drives to the mount points like sda/sdb so it's internally consistent with how it's been configured. Pretty much a PITA to correct.

udev itself kind of plays a role in which drives get picked for what mount point, so I guess you could putz around with it, but meh, so much easier to just unplug everything and repartition and format the drive. Just make sure to wipe the seagate before plugging it back in and use gparted to add whatever.

azith28

K thats not really viable. I do not have install discs, I am using a ghost image of our highly customized version of suse.

Tell you what. Maybe if you told me how i would go about removing the grub/ boot loader i could reimage the ST drive, remove it, then wipe partitions and such.

bowen

http://www.reactivated.net/writing_udev_rules.html

knock yourself out then

I won't have much luck helping you fix your grub/boot loader, that's highly specific to your highly customized version of suse.

Nija

From here:



If your computer has more than one hard disk, you can specify the boot sequence of the disks to match the BIOS setup of the machine (see Section 11.1.2, The File device.map). To do so, proceed as follows:
Setting the Disk Order

Open the Boot Loader Installation tab.

Click Boot Loader Installation Details.

If more than one disk is listed, select a disk and click Up or Down to reorder the displayed disks.

Click OK two times to save the changes.

Sounds like you should be able to adjust the boot sequence to your desired outcome.

azith28

Thats good info thanks Nija. I think its what i needed. I cant quite do that easily because the braniacs that made the custom suse uninstalled grub after setting it up, but that device.map file is probably what explains the issue because it says grub cant read hd information from cmos.