Enterthe no tacacs-server
        command to remove any TACACS + server configuration.
      device(config)# no tacacs-server
        <host>
 Enterthe no radius-server
       command to remove any RADIUS server configuration.
      device(config)# no radius-server
        <host>
 Enterthe no ldap-server
       command to remove any LDAP server configuration.
      device(config)# no ldap-server
        <host>