Flash drives tend to have firmware ahead of the "drive" access and sometimes that means that they simply will not work as a boot device.
I am having good luck with Kingston DataTraveler G4 series drives. What I do to load a Linux (Ubuntu 12 and Fedora 20 tried so far) is to first work with Gparted. The drive has some unallocated space before the main data partition - which I make sure I do not touch. What I do is simply - starting from the end of the data portion - shorten that portion to make space for the Linux. Then I install the Linux using the normal live DVD installer to the flash drive into the large unallocated space I just created - having it make an MBR on the device. If the bios on your oldish computer will allow booting from flash drives I think it is not a bad approach. I have made Clonezilla images of some of my thus formed flash drives which do work well. But I have not tried using those images to make a new drive from the saved image. The thing is that the process of making an updated LInux on a drive takes a long time. If this works it will save a lot of time (for my projects with these drives) and in your situation it would be good to keep a working spare as flash drives, at least for me, tend to simply stop working after a year or two. Please do let us know how it works out. On Sun, Aug 31, 2014 at 12:40 PM, Chris Murphy <li...@colorremedies.com> wrote: > > On Aug 31, 2014, at 9:00 AM, D. Hugh Redelmeier <h...@mimosa.com> wrote: > > > I have an oldish PC that only understands booting from 512-byte > > sectors and then only with MBR disks. > > > > I want to install large new disks on it, and no old disks. These > > don't even pretend to do 512-byte sectors: 4k all the way (3T and 4T > sizes > > aren't good for MBR either). > > Uhhh, I haven't seen bare drives in the wild with 4096 byte logical and > physical sectors. What's the model of this drive? I've only seen some USB > enclosures that do this, and present a 4096 byte logical sector: and only > then they come with a drive already in them, they're not empty enclosures. > The problem some people have is if the enclosure craps out they try to > recover their data and they're SOL because the enclosure caused the drive > to present 4096 logical sectors, but the drive itself presents 512 byte > logical sectors, and the mismatch makes the drive unreadable, unmountable, > because all the reported LBAs are totally wrong. So you have to get a > replacement enclosure… well at least, that's the easiest way to deal with > it. Maybe someone could hack up a way to do the same thing as the enclosure > in software with device mapper (?), that'd be useful. > > Old PC's might be OK with GPT so long as there's also a protective MBR. By > default anaconda/blivet (the Fedora installer), creates a protective MBR, > but also sets a non-standard flag its 0xEE entry that tricks most computer > BIOS into accepting GPT. But there are quite a few BIOS that will just face > plant. So you have to test it to know for sure. > > > > I was thinking that I should be able to use a USB flash memory stick > > as the boot device, loading GRUB from there, and then having it boot > > the OS from a big GPT hard disk. The stick would be permanently > > plugged in. > > > > Is there any reason that this might not work? Is there a better way? > > You could try the above. If not then fall back to your idea. At install > time, choose both flash drive and hard drive as installation destinations. > Put the /boot mount point on the flash drive, and everything else on the > hard drive. > > > > > > Are there special GRUB modules that I need to convince GRUB's > > installer to put on the USB stick? > > No. grub2-install will figure this out, anaconda has already mounted the > system as it will be used, and has written an fstab that describes how it's > to be mounted, and grub2-install reads that and figures out that the flash > drive with /boot on it should receive grub's core.img embedded in the MBR > gap. Once that core.img is read, the BIOS is out of the picture. > > > What filesystem type is best for the USB stick? My guess: ext4 is > > fine. > > Doesn't really matter it's mainly read-only. It'll only be written to when > doing kernel updates. > > > Chris Murphy > -- > users mailing list > users@lists.fedoraproject.org > To unsubscribe or change subscription options: > https://admin.fedoraproject.org/mailman/listinfo/users > Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct > Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines > Have a question? Ask away: http://ask.fedoraproject.org >
-- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org