Ok, I just managed, after much effort, to rebuild my USB key to install
CentOS 6. There are a number of changes.
Partition the USB key, but make partition 1, Win 95 (FAT32) (I think
that's partition type "b"), bigger. I made it 500M. The rest should be
ext3 (or whatever).
Format the partitions. Make sure to toggle the bootable flag on partition 1.
syslinux /dev/<DOS partition>
When you're done, the DOS partition should look like this:
ls -laF /mnt
Under /boot is /grub, and it's contents. Make sure you create a grub.conf
to put in there.
If syslinux didn't put it there, mount your .iso, and copy
/mnt/iso/isolinux into there, then rename /syslinux/isolinus.cfg to
/syslinux/syslinux.cfg. I put a grub.conf here, too:
title @PRODUCT@ @VERSION@
title Install system with basic video driver
kernel @KERNELPATH@ xdriver=vesa nomodeset askmethod
kernel @KERNELPATH@ rescue askmethod
On the second partition, copy your .iso images. Then copy /mnt/iso/images
You should be good to go.
NOTE: during the install, if you make any partitions encrypted, it will
hang when it's done formatting, so reboot, and tell it to install again,
and then not to format. It will start, then ask for the password, then
actually go through the install.
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