Using the undo Command

If a command line begins with the keyword undo, it is an undo command. An undo command is generally used to restore a default configuration, disable a function, or delete a configuration. Most configuration commands have a corresponding undo command.

Some examples of using the undo command are listed as follows:

• The undo command restores the default setting.

  The sysname command sets a device host name. For example:

  <HUAWEI> system-view
  [HUAWEI] sysname Server
  [Server] undo sysname
  [HUAWEI]

• The undo command disables a specified function.

  The ftp server enable command enables the FTP server function on the device. For example:

  <HUAWEI> system-view
  [HUAWEI] ftp server enable
  Warning: FTP is not a secure protocol, and it is recommended to use SFTP.
  Info: Succeeded in starting the FTP server.
  [HUAWEI] undo ftp server
  Info: Succeeded in closing the FTP server. 

• The undo command deletes a specified configuration.

  The header command configures the header information displayed on terminals when users log in. For example:

  <HUAWEI> system-view
  [HUAWEI] header login information "Hello,Welcome to Huawei!"

  Log out of the terminal and re-log in. A message "Hello, Welcome to Huawei!" is displayed before authentication. Run the undo header login command.

  Hello,Welcome to Huawei!
  
  Login authentication
  
  
  Password:
  Info: The max number of VTY users is 20, and the number
        of current VTY users on line is 5.
        The current login time is 2012-06-09 04:46:00.
  <HUAWEI> system-view
  [HUAWEI] undo header login

  Log out of the terminal and re-log in. No message is displayed before authentication.

  Login authentication
  
  
  Password:
  Info: The max number of VTY users is 20, and the number
        of current VTY users on line is 5.
        The current login time is 2012-06-09 04:52:10.
  <HUAWEI> 

The command output provided here is used for reference only. The actual output information may differ from the preceding information.