What role does the private key play when connecting via ssh? How can it be used?

Question

SSH

It is not clear what role the private key plays, if the public key is enough for communication and it is registered in the authorized_keys on the server. Is it possible to use only the private key to connect?

Answer 1

of course plays: the ssh client uses it when connecting.

With key pair authentication, a pair of public and private keys is pre-generated for a specific user. On the machine from which you want to connect, the private key is stored, and on the remote machine, the public key. These files are not transferred during authentication, the system only checks that the owner of the public key also owns the private one. With this approach, as a rule, automatic login on behalf of a specific user in the OS is configured.

https://ru.wikipedia.org/wiki/SSH#Technical_info...