Variations on banner Command Output

Variations on banner Command Output

The banner command output varies between the Telnet and different versions of SSH connections. This table illustrates how different banner command options work with various types of connections.

Banner Command Option

Telnet

SSH v1 only

SSH v1 and v2

SSH v2 only

banner login Displayed before logging into the device. Not displayed. Displayed before logging into the device. Displayed before logging into the device.
banner motd Displayed before logging into the device. Displayed after logging into the device. Displayed after logging into the device. Displayed after logging into the device.
banner exec Displayed after logging into the device. Displayed after logging into the device. Displayed after logging into the device. Displayed after logging into the device.

Unable to Display the Login Banner

SSH version 2 supports the login banner. The login banner is displayed if the SSH client sends the username when it initiates the SSH session with the Cisco router. For example, when the Secure Shell ssh client is used, the login banner is displayed. When the PuTTY ssh client is used, the login banner is not displayed. This is because Secure Shell sends the username by default and PuTTY does not send the username by default.

The Secure Shell client needs the username to initiate the connection to the SSH enabled device. The Connect button is not enabled if you do not enter the host name and username. This screenshot shows that the login banner is displayed when Secure Shell connects to the router. Then, the login banner password prompt displays.

 

The PuTTY client does not require the username to initiate the SSH connection to the router. This screenshot shows that the PuTTY client connects to the router and prompts for the username and password. It does not display the login banner.

 

 

This screen shot shows that the login banner is displayed when PuTTY is configured to send the username to the router

 

 

 

Advertisements
Posted in Linux

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: