[CentOS] CentOS-5.5 Live CD & netinstall

Sat Apr 9 14:43:58 UTC 2011
William Hooper <whooperhsd at gmail.com>

On Fri, Apr 8, 2011 at 10:04 PM, William Hooper <whooperhsd at gmail.com> wrote:
> On Fri, Apr 8, 2011 at 8:56 PM, Timothy Murphy <gayleard at eircom.net> wrote:
>> In my case, at least, I would always run a Live CD before installing an OS,
>> just to make sure it runs OK.
>> So a person might well have a Live USB stick anyway.
>
> This is a valid point.
>
> What booting system does the LiveCD use after transferring it to the
> USB stick?  Perhaps a middle ground would be to create a wiki page on
> how to add the netinstall kernel/initrd to your own media.

I did some testing to answer my own question.  As I expected, adding
the option back yourself on a USB stick is trivial (for a CD you would
have to complete your own isolinux burn, so it is a little more
involved, but the same basic steps).  I believe most Linux bootable
USB sticks use syslinux, so these steps would work with them, also.

1) Create Live USB stick as before

2) Edit the isolinux/isolinux.cfg or syslinux/syslinux.cfg on the USB
stick to add a stanza to boot the installer kernel (this example taken
from the 5.5 LiveCD)
====start here=====
label installer
  menu label Network Installation
  kernel vminst
  append initrd=install.img text
====stop here=====

3) Copy the kernel/initrd images from any mirror onto the USB stick
(making sure they are named the same as your stanza above):
http://centos.mirror.netriplex.com/5.6/os/i386/images/pxeboot/vmlinuz
-> syslinux/vminst
http://centos.mirror.netriplex.com/5.6/os/i386/images/pxeboot/initrd.img
-> syslinux/install.img

4) Boot to USB stick, press space to get the menu, choose whatever you
labeled your stanza (in this case "Network Installation".

I believe that the installer still changes for each point release, so
you would have to make sure the kernel/initrd is for the specific
release you want.  In fact, this would let you create a number of
different stanzas so that you could boot the installers for multiple
versions if you wanted to (Fedora 14, CentOS 5.6, and CentOS 6.0 for
example).


-- 
William Hooper