Ask HN: How to regain access to my dedicated server?

it might be a good idea to ask your server provider/hoster if they have a rescue console. Many big provider offer this service to simply remote install any OS of your desire (or a predefined mini linux rescue shell). The rescue console mostly works like this: The hoster has an internal tftp (yes, tftp) where the server can boot any iso from. So the main boot sequence is something like this:

1: boot from network (tftp) 2: boot from medium (cd, usb, etc.) 3: boot from disk

I once had an issue with my Firewall and the usb driver that the KVM switch provided just outputted strange signs, so it was unuseable. But a quick boot into the rescue console, mounting the HD and changing the Firewall config made it all a breeze.

Greets,

Chris