There are lots of good rescue CD’s out there. The one I have used for the last 12 years is System Rescue CD. Why? As well as lots handy tools the key feature I have used countless times is that it easily runs a SSH server. Imagine you need to fix a machine that is in a difficult place to work. Imagine it is in a different office even a different country! You can SSH in and try and fix it. I have used this disk to work on servers thousands of miles away. It works happily on workstations and laptops even if they do not run Linux. Importantly it works well on VM’s that you can boot from CD
Getting remote access is easy. Boot from the CD, choose a keymap (or take the default), set the root password with
and finally find the IP address you have been given with
Connect to it as root. From there you have full access to command line tools to try and fix or recover files from the machine. Often it is a case of mounting the disk, and using rsync to copy everything off. For windows networks the CD can run a Samba share (just look at the /etc/smb.conf for more information.
Being a Linux based CD you can run chroot on a mounted disk to sometimes run a service from the broken install if it too is Linux based.
One very useful tool that only runs on the supplied Xwindows desktop is gparted. This allows you easily to modify partitions including allocating more space to partitions as long as they are Ext3 or Ext4. As I say it only works on Xwindows but if you have a Linux desktop you can use SSH to run programs from one machine to another so this works too. Simply connect to the machine running SystemRescue with ssh -X
Go to the homepage at – https://www.system-rescue.org/ – for lots of really useful ideas on how to fix things for both Linux and Windows.