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2.
The server authenticates the client. If the authentication fails, the server sends the client a message
to inform the client of the failure and the methods available for re-authentication.
3.
The client selects a method from the list to initiate another authentication.
4.
The preceding process repeats until the authentication succeeds or the number of failed
authentication attempts exceeds the maximum of authentication attempts. In the latter case, the
server tears the session down.
Only clients running SSH2.0 or a later version support password re-authentication that is initiated by the
switch acting as the SSH server.
Session request
After passing authentication, the client sends a session request to the server, and the server listens to and
processes the request from the client. If the server successfully processes the request, the server sends an
SSH_SMSG_SUCCESS packet to the client and goes on to the interaction stage with the client.
Otherwise, the server sends an SSH_SMSG_FAILURE packet to the client to indicate that the processing
has failed or that it cannot resolve the request.
Interaction
In this stage, the server and the client exchange data as follows:
1.
The client encrypts and sends the command to be executed to the server.
2.
The server decrypts and executes the command and then encrypts and sends the result to the client.
3.
The client decrypts and displays the result on the terminal.
In the interaction stage, you can execute commands from the client by pasting the commands in text
format (the text must be within 2000 bytes). The commands must be available in the same view.
Otherwise, the server might not be able to perform the commands correctly.
If the command text exceeds 2000 bytes, you can execute the commands by saving the text as a
configuration file, uploading the configuration file to the server through SFTP, and then using the
configuration file to restart the server.
Configuring the switch as an SSH server
SSH server configuration task list
Task Remarks
Generating a DSA or RSA key pair
Required
Enabling the SSH server function
Required
Configuring the user interfaces for SSH clients
Required
Configuring a client public key
Required for publickey authentication users and
optional for password authentication users
Optional
Setting the SSH management parameters
Optional
Содержание A5830 Series
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