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Using Client-Based SSH Authentication
To SSH from the chassis to the SSH client, use the following command.
This method uses SSH version 1 or version 2. If the SSH port is a non-default value, use the ip ssh server port number command
to change the default port number. You may only change the port number when SSH is disabled. Then use the -p option with the ssh
command.
• SSH from the chassis to the SSH client.
ssh ip_address
Example of Client-Based SSH Authentication
Dell#ssh 10.16.127.201 ?
-l User name option
-p SSH server port option (default 22)
-v SSH protocol version
Troubleshooting SSH
To troubleshoot SSH, use the following information.
You may not bind id_rsa.pub to RSA authentication while logged in via the console. In this case, this message displays:%Error: No
username set for this term.
Enable host-based authentication on the server (Dell Networking system) and the client (Unix machine). The following message appears if
you attempt to log in via SSH and host-based is disabled on the client. In this case, verify that host-based authentication is set to “Yes” in
the le ssh_cong (root permission is required to edit this le): permission denied (host based).
If the IP address in the RSA key does not match the IP address from which you attempt to log in, the following message appears. In this
case, verify that the name and IP address of the client is contained in the le /etc/hosts: RSA Authentication Error.
Telnet
To use Telnet with SSH, rst enable SSH, as previously described.
By default, the Telnet daemon is enabled. If you want to disable the Telnet daemon, use the following command, or disable Telnet in the
startup cong. To enable or disable the Telnet daemon, use the [no] ip telnet server enable command.
Example of Using Telnet for Remote Login
Dell(conf)#ip telnet server enable
Dell(conf)#no ip telnet server enable
VTY Line and Access-Class Conguration
Various methods are available to restrict VTY access in the Dell Networking OS. These depend on which authentication scheme you use —
line, local, or remote.
Table 93. VTY Access
Authentication Method VTY access-class support? Username access-class
support?
Remote authorization support?
Line YES NO NO
Local NO YES NO
TACACS+ YES NO YES
RADIUS YES NO YES
920 Security