[CentOS] kexec for CentOS 4?

[Tom Georgoulias]

On 03/02/2010 10:04 AM, Tony Mountifield wrote:
> In article<4B8D1650.1060001 at mcclatchyinteractive.com>,
> Tom Georgoulias<tomg at mcclatchyinteractive.com>  wrote:
>> On 03/02/2010 05:10 AM, Tony Mountifield wrote:
>>> I have a remote CentOS 4 machine on a network where I can't put a DHCP
>>> or PXE server, and I want to do a complete reinstall. So what I want to
>>> do is, from the currently-running system, to invoke an installation
>>> kernel and initrd in just the same way that GRUB would, giving it a boot
>>> command line that specifies a remote kickstart file, installation tree,
>>> and other required info.
>>
>>> If not, are there any other ways to achieve what I've described?
>>
>> I would use cobbler and koan for this.  Once you have a cobbler server
>> setup for the kickstart (which is super easy to do), you can use koan
>> with the --replace-self and -k options and do exactly what you want.
>
> Can this be done even if I can't put the cobbler server on the same
> network as the box I want to re-install? The information I found on
> cobbler suggested to me that it was a tying together of DHCP, PXE,
> kickstart and install tree. As I understand it, the DHCP and PXE/TFTP
> servers have to be local, and also I have to have the box able to perform
> a PXE boot. So if the box in question is remote and on a network that
> I don't control or have any other boxes on, I suspect cobbler and koan
> wouldn't work.
>
> I could well have misunderstood - I found very little detail about koan
> apart from the command line options.

You can use cobbler and install clients without DHCP/PXE.  When you run 
koan, you pass in all of the normal kickstart options you would use to 
configure a static network interface (ip, netmask, gateway, dns, 
ksdevice, etc.).  Koan will download the kickstart config and 
initrd/vmlinuz images you need to boot up, plus add all of the grub 
entries you need to automatically get into the kickstart after a reboot. 
  On your next reboot, it will choose that entry in grub, immediately go 
into kickstart mode, and follow the config in the ks.cfg file that it 
pulled from the cobbler server.

Tom