1-22Configuring whether first-time authentication is supportedWhen the device connects to the SSH server as an SSH client, you can configure whether the devicesupports first-time authentication.z With first-time authentication enabled, an SSH client that is not configured with the server hostpublic key can continue accessing the server when it accesses the server for the first time, and itwill save the host public key on the client for use in subsequent authentications.z With first-time authentication disabled, an SSH client that is not configured with the server hostpublic key will be denied of access to the server. To access the server, a user must configure inadvance the server host public key locally and specify the public key name for authentication.Follow these steps to enable the device to support first-time authentication:To do... Use the command... RemarksEnter system view system-view —Enable the device to supportfirst-time authentication ssh client first-time enableOptionalBy default, the client is enabled torun first-time authentication.Follow these steps to disable first-time authentication support:To do... Use the command... RemarksEnter system view system-view —Disable first-time authenticationsupport undo ssh client first-timeRequiredBy default, the client is enabled torun first-time authentication.Configure server public key Refer to Configuring the Public Keyof a Client on the ServerRequiredThe method of configuring serverpublic key on the client is similar tothat of configuring client public keyon the server.Specify the host key name of theserverssh client { server-ip |server-name } assign publickeykeynameRequiredWith first-time authentication enabled, an SSH client that is not configured with the SSH server's hostpublic key saves the host public key sent by the server without authenticating the server. Attackers mayexploit the vulnerability to initiate man-in-middle attacks by acting as an SSH server. Therefore, it isrecommended to disable first-time authentication unless you are sure that the SSH server is reliable.Specifying a source IP address/interface for the SSH clientYou can configure a souce IP address or the souce IP address by specifying the correspondinginterface for the client to use to access the SSH server. This improves the service manageability whenthe SSH client has multiple IP addresses and interfacesFollow these steps to specify a source IP address/interface for the SSH client:
