Remote Recovery mode
The c3os recovery mode can be used to recover a damaged system, or to regain access remotely (with assistance) to a machine which has been lost access to. The recovery mode is accessible only from the GRUB menu, from both the LiveCD and an installed system.
On installed system there are two recovery modes available during boot. Below it is described only how the c3os remote recovery works. The manual recovery entry has nothing special from the standard Elemental-toolkit recovery mode. It can be used to reset the A/B partitions (with the user/pass used during setup) and perform any other operation without remote access.
Boot into recovery mode
c3os recovery mode can be accessed either via ISO or from an installed system.
A GRUB menu will be displayed:
Select the last entry c3os (remote recovery mode) and press enter.
At this point the boot process starts and you should be welcomed by the c3os screen:
After few second the recovery process starts, and right after a QR code will be printed out of the screen along with a password which can be used later on to SSH into the machine:
At this stage, take a screenshot or a photo, just save the image with the QR code.
Connect to the machine
In another machine you are using to connect to your server (your workstation, a jumpbox, or ..) use the c3os CLI to connect over the remote machine:
$ ./c3os bridge --qr-code-image /path/to/image.png
INFO Connecting to service kAIsuqiwKR
INFO SSH access password is yTXlkak
INFO SSH server reachable at 127.0.0.1:2200
INFO To connect, keep this terminal open and run in another terminal 'ssh 127.0.0.1 -p 2200' the password is yTXlkak
INFO Note: the connection might not be available instantly and first attempts will likely fail.
INFO Few attempts might be required before establishing a tunnel to the host.
INFO Starting EdgeVPN network
INFO Node ID: 12D3KooWSTRBCTNGZ61wzK5tgYvFi8rQVxkXJCDUYngBWGDSyoBK
INFO Node Addresses: [/ip4/192.168.1.233/tcp/36071 /ip4/127.0.0.1/tcp/36071 /ip6/::1/tcp/37661]
INFO Bootstrapping DHT
At this point the bridge should start, and you should be able to see connection messages in the terminal. You can connect to the remote machine by using ssh and pointing it locally at 127.0.0.1:2200. The username is not relevant, the password is print from the CLI.
The bridge operates in the foreground, so you have to kill by hitting CTRL-C.