Q:

How to rebuild a Redhat Machine Remotely

I need to rebuild a few machines with redhat, I have used Koan before to do this on remote systems, but we are not using cobbler so this option is out. 
I have an idea how to do this by copying the vmlinuz and initrd.img to somwhere (not where to put them) and then add an entry to grub with these two set.  Then reboot and when it boots it picks up a kickstart and rebuilds itself. 
Has anyone got any ideas how to do this? 
Thanks :)

A:

You are on the right track.   Do you have another host you can host the installation source on? 
Copy the vmlinuz and initrd.img file to /boot. 
Create an entry in Grub. 
title Reinstall Red Hat Enterprise Linux
root (hd0,0)
kernel /vmlinuz ks=http://path/to/ks.cfg
initrd /initrd.img 
This assumes you are Kickstarting via an HTTP source.   You can modify this for your environment.   Note also that you may need to include other options here for your particular environment.   The kernel line is the line to pass these options. 
You can either set the default entry in the grub.conf file or from the shell with the grub command.   (Doing it in the grub.conf is really easiest...)
# grub
grub> savedefault --default=1 --once
grub> quit 
Where --default=1 is the corresponding Grub entry in your /etc/grub.conf file. ( Remember to start counting from zero.)   
Then reboot right into Anaconda!~  If you are doing this truly remotely.. Please, please test your Kickstart file to ensure it will be 100% non-interactive. 
Here is a more in depth article on the subject that even covers monitoring the installation remotely over VNC: How to use Kickstart (Anaconda's remote control)

