SuSE Restart vs Shutdown
Yesterday I wanted to boot from a CD so I checked to "restart" option. The system rebooted and at the correct point I got into the BIOS to make sure the CDROM would be the boot device. Then when it got to the point of rebooting the computer ended up in SuSE 10. I then told SuSE to "turn off the computer", which it did. After powering on the computer if booted off the CDROM. My question: Does SuSE somehow force the computer to bypass the boot sequence set in the BIOS when it is told to "restart"? If so, anyone know how this is done? Thanks for any insite Terry -- SUSE LINUX 10.0 (i586) -- 2.6.13-15.12-default -- Sun 10/01/06 1:10pm up 17:03, 3 users, load average: 0.50, 0.46, 0.42
Terry Eck wrote:
Does SuSE somehow force the computer to bypass the boot sequence set in the BIOS when it is told to "restart"? If so, anyone know how this is done?
No, SUSE (nor anyone else) cannot override the boot-sequence set in the BIOS. /Per Jessen, Zürich
On Sun, 2006-10-01 at 20:28 +0200, Per Jessen wrote:
Terry Eck wrote:
Does SuSE somehow force the computer to bypass the boot sequence set in the BIOS when it is told to "restart"? If so, anyone know how this is done?
No, SUSE (nor anyone else) cannot override the boot-sequence set in the BIOS.
Assuming you get to the BIOS, this is true. But with kexec, there is work being done on accomplishing a true "warm boot", where you reboot without ever touching the BIOS. As I understand it, the kernel simply shuts down everything, loads the new kernel (if applicable), and launches it But since Terry mentioned that he was in the BIOS settings editor he was already outside the linux kernel, so this is obviously not relevant, so sorry for mentioning it :)
Actually, SUSE does NOT bypass your BIOS settings, *but* it has 2 bootloaders, one on the CD-ROM and other in the Hard Disk, so you migh boot from CD-ROM wait for 10 seconds, and if you don't pressed any buttons, it boot from Hard Disk. So *watch* carefully what bootloader runs after restart. (and don't blink) The two bootloaders look the same but have one *big* diffrence - bootloader on CD has first option to "boot from Hard Disk", while bootloader on Hard Disk has no such option, because it already booted from HDD.
On Sun, 2006-10-01 at 13:22 -0500, Terry Eck wrote:
Yesterday I wanted to boot from a CD so I checked to "restart" option. The system rebooted and at the correct point I got into the BIOS to make sure the CDROM would be the boot device. Then when it got to the point of rebooting the computer ended up in SuSE 10. I then told SuSE to "turn off the computer", which it did. After powering on the computer if booted off the CDROM. My question:
Does SuSE somehow force the computer to bypass the boot sequence set in the BIOS when it is told to "restart"? If so, anyone know how this is done?
Thanks for any insite
This happens with disturbing frequency on my machine, the BIOS often doesn't detect a CD or DVD in the player and jumps to the harddisk directly. It's either a BIOS bug or a problem with my DVD player, I haven't decided which yet It is theoretically possible to change BIOS settings from inside an operating system, for example my thinkpad has a program (for windows) which changes the password/firgerprint settings. This could be made to change any BIOS setting, including the boot order. But as far as I'm aware, there is no such functionality in linux at this time
participants (4)
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Alexey Eremenko -
Anders Johansson -
Per Jessen -
Terry Eck