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SSH server function
SSH server function supports the remote logging function (ssh server) similar to TELNET server function and
remote file transfer function FTP
（
sftp server) similar to server function. In TELNET server function and FTP server
function, it is feared that the content of the communicationmay be intercepted when communicating like the
plain text data. In SSH server function, by host authentication and encryption communication, the login
function and the file transfer function can be safely trusted and used.
At the time of Power on and reset of this device SSH host authentication key of this device is generated. The
generation time is from few seconds to few minutes. At the time of start and completion of SSH hos
authentication key generation there is syslog output, and SSH can be connected to this device from the point
where generation is complete. When it is necessary to set other connected SSH host authentication key in the
SSH client software beforehand, set the SSH host authentication key displayed by executing 'show ssh server
key dsa' command and 'show ssh server key rsa' command in this device.
In this device when SSH is connected by sending the SSH host authentication key of this device to SSH client
side and if the set and saved key differ, the SSH connection is rejected. Therefore, SSH is connected by resetting
or by deleting the SSH host authentication key which is set and saved in SSH client software by device
exchange etc.
After that, enter password prompt is displayed but it may take some time until it is displayed by SSH host
authentication process. Moreover, the SSH server function can be completely aborted by setting the serverinfo
ssh / serverinfo sftp command to ‘off’.
In order to connect the ssh client and the sftp client with the SSH port and when either of ssh or sftp of the
serverinfo command is 'on', SSH port of this device can be connected as it is in the same state. And when set to
'off', it cannot be connected until the password is input.
Points to be noted
It takes time to generate SSH host authentication key when it reflects that either of the SSH functionin
serverinfo command is validated by starting this device in a state where the SSH server function is completely
terminated. At this time, there is a possibility to effect other processes as the session monitor
time-out is generated.
