[PLUG] Remote host lost ssh key verification [UPDATED]

[King Beowulf]

On 02/24/2017 01:01 PM, Rich Shepard wrote:
> On Fri, 24 Feb 2017, King Beowulf wrote:
> 
>> On DESTINATION computer: delete ~/.ssh/authorized_keys
> 
> Ed,
> 
>    That's the problem: there's no public key for this laptop in
> ~/.ssh/authorized keys!
> 
>    If I copy the laptop's /etc/ssh/ssh_host_ed25519_key.pub to a thumb drive
> and from there to the desktop's ~/.ssh/authorized_keys it is associated with
> root@<laptop_hostname>. The existing public key in authorized_keys is
> associated with rshepard@<laptop_hostname>.
> 
>    How do I transfer the laptop's ed25519_key.pub to the desktop with
> assignment to me as the authorized user?
> 
> Rich
> _______________________________________________

for ssh or scp (cp over ssh), you only need one pub key for the
connection to work.  NOT the ones in /etc/ssh.  One of the ones in ~/.ssh

take the laptop's *.pub to the desktop, and do the same for the desktop.
 pick whatever algorithm you want - I use the 4069-bit rsa.

cat laptop_key.pub > ~/.ssh/authorized_keys

That should do it as long as you know the passphrase.  You can cache the
passphrase with ssh-add if you have ssh-agent running.

My server has 2 keys in ~/.ssh/authorized_keys: one that allows local
ssh on my network, another for remote ssh from "outside" and since its
"headless" none of its pub keys exist anywhere else.