Hi,

I'm looking if it is possible to change the whole Linux install without having to boot up using a live-cd.
The purpose is to remotely log on to a machine using SSH or other to replace the complete installation, without loosing network setup so I don't loose contact with it.
Perhaps loading the live-cd while linux is already running?
Can anyone help me with this?

Thanks in advance,

Bart Garrein

Hello and Welcome to LinuxQuestions,

You're not making a lot of sense in my opinion, at least I personally don't understand what you want/need. How would you 'reinstall' a system without loosing network connection? At some point you'll always loose your network connection if you're switching to the 'new' install. Can you please elaborate on what you're trying to obtain? And also, it wouldn't be a bad idea to as the site admin Jeremy to change your nick. Putting your email as nick is a pretty bad idea, that is if you don't like spam.

Kind regards,

Eric

Hi Eric,

Thanks for the quick response. You have to image two systems. One embedded on one side of the planet and one normal system on the other. One of the systems should be able to completely overwrite the other without loosing connection. That would be the ideal world.
Of course when I reboot (bad term) I will loose connectivity. But the point is that I need the other system to get in a state where a second linux is turning in RAM so I can overwrite the ROM. (Here I meant the comparison with the live-cd) But once overwritten, I need to be able to change network settings that are default on the overwritten system, otherwise when I reboot, I will have a permanent lost connection and intervention will be inevitable. What I don't want of course.

To do some tests on this, I was trying to start a little project to try to update a system remotely. The questions that had risen were:
Is there a possibility to load something like a live-cd while linux is already running?
If so, can the files be placed on a mount instead of a cd-rom?
And if the last is possible, can the updated version of linux (not running at the moment) be updated itself to another network configuration so it will connect again to the network as nothing ever happened?

Kind regards,

Bart Garrein

On a Debian system it is possible, if you have a spare partition on your mass storage device. You can mount this partition, then install a new base system with debootstrap. After that you copy the network settings from your old install, chroot into your new system and customize it as you need. If you are ready with that setup the bootloader to boot into the new system and reboot.

I think the simplest way is going to be via a temporary dual boot as in

1. obtain enough space to install the core of the new system. ~5GB ?
2. install new system
3. set orig grub (old system) to default to new system
4. issue reboot
5. HW will boot new system
6. remove old system
7. complete remaining install requirements

Or try a PXE install eg http://www.howtoforge.com/ubuntu_pxe_install_server

The best way to perform remote administration is to virtualize the Linux instance that's on the other side of the planet. Install it under VMWare or the like. Then you can manipulate the OS to your heart's content. If you fat-finger a network configuration and lose all connectivity, you'll still be able to access tty0 via the VM layer.