Host Key Unknown
Host authentication enables the Secure Shell client to reliably confirm the identity of the Secure Shell server. This authentication is done using public key authentication. If the host public key has not previously been installed on the client, the first time you attempt to connect you see a message indicating that this is an unknown host. This message includes a fingerprint that identifies the host. To be sure that this is actually your host, you should contact the host system administrator who can confirm that this is the correct fingerprint. Until you know that the host is actually your host, you are at risk of a "man-in-the-middle" attack, in which another server poses as your host.
The options are:
| Option | Description |
|---|---|
| Always | Make the connection and add this host to the list of trusted hosts. You will not see this prompt for subsequent connections to the same host unless you remove the host from the trusted host list, or the host key changes. |
| Once | Make the connection but do not add the host to the trusted host list. You will see this prompt again the next time you make a connection to the same host. |
| No | Do not make the connection and do not add the host to the trusted host list. |
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