[CentOS] Building an install disk on a USB key manually or using unetbootin

Fri Jul 23 14:46:11 UTC 2010
Bowie Bailey <Bowie_Bailey at BUC.com>

 On 7/22/2010 6:09 PM, David wrote:
> Has anyone successfully built a USB key for installing centos5.5 either 
> manually or using a tool like unetbootin?
> I am trying to create one using the 64bit install DVD iso and so far the 
> USB either won't boot (unetbootin) or the installation aborts after I 
> select the iso location on the USB key (manual).

I was able to successfully install CentOS 32-bit from an 8GB USB flash
drive (4GB is not quite big enough, even for i386) created with this

    Create a 10M DOS partition on the USB drive and make it active
    Create Linux partition using the rest of the drive

    mkfs -t vfat /dev/<USB DOS partition>
    mkfs /dev/<USB Linux partition>

    liveCD-iso-to-disk <boot.iso> /dev/<USB DOS partition>
    mount /dev/<USB Linux partition> /mnt
    rsync --progress <CentOS.iso> /mnt/

You can get the boot.iso by loop-mounting the CentOS iso and pulling it
out of the /os/i386/images directory, or grab it from one of the mirrors
(the mirror links on the CentOS site link directly to the install isos,
so you'll have to browse up a few directories and then go back down to
find the images directory).

I used 'rsync' here because I hate having a copy process run for 10
minutes with no progress indication.  :)

The only problem I found was that the install insisted on installing
grub on the USB drive rather than the target hard drive.  I finally had
to skip the grub installation and install it by hand afterwards.