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Booting from CD when a systems BIOS won't let you

Along the way on my permissions nightmare last night, I made matters worse by changing permissions on a fairly important file. In order to fix that I was going to need to reboot from a boot disk. The…

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Avery J. Parker

IT veteran, maker educator, and author of Network Ninja, 3D Printing Mastery, and AI Workflow Mastery. Business IT: Diversified Tech Solutions.

Along the way on my permissions nightmare last night, I made matters worse by changing permissions on a fairly important file. In order to fix that I was going to need to reboot from a boot disk. The only problem was boot floppys typically don't come with reiserfs support (only the boot cds I've found have that.) AND my server has for some time refused to boot from the CD. Now, the BIOS will let you choose CD as the first boot device but it promptly decides that there is a "BIOS checksum mismatch" and reloads the defaults which leaves you booting from floppy, then hard drive.... Now, I've changed the CMOS battery twice within a 2 month span and I think the longest things lasted were about a week before it reverted to that "BIOS checksum mismatch" (For those of you smart enough to suggest I replace the CMOS battery.) Now, it could be that the battery I replaced with had expiired it's shelf life already I suppose. But....


at this point in my permissions adventure I didn't have the inclination to start excavating so I could pull the case and try a THIRD CMOS battery out. Instead I wanted a floppy to just boot from that could load the cdrom drive. I found this ubuntu help page talking about Smart Boot Manager. Now the official site is supposed to be http://btmgr.webframe.org/ but I get a page not found at that site. But there is a sourceforge download page http://btmgr.sourceforge.net/download.html

All in all sbm (smart boot manager) looks like a good utility to have on hand for those systems that are cantankerous enough to not boot the way you want.... nice utility.