1-2 
 
To improve security and prevent attacks to the unused Sockets, TCP 23 and TCP 22, ports for Telnet 
and SSH services respectively, will be enabled or disabled after corresponding configurations. 
z  If the authentication mode is none, TCP 23 will be enabled, and TCP 22 will be disabled.  
z  If the authentication mode is password, and the corresponding password has been set, TCP 23 will 
be enabled, and TCP 22 will be disabled. 
z  If the authentication mode is scheme, there are three scenarios: when the supported protocol is 
specified as telnet, TCP 23 will be enabled; when the supported protocol is specified as SSH, TCP 
22 will be enabled; when the supported protocol is specified as all, both the TCP 23 and TCP 22 
port will be enabled. 
 
Examples 
z  Example of the password authentication mode configuration 
# Configure to authenticate users using the local password on the console port, and set the 
authentication password to aabbcc in plain text. 
<Sysname> system-view 
System View: return to User View with Ctrl+Z. 
[Sysname] user-interface aux 0 
[Sysname-ui-aux0] authentication-mode password 
[Sysname-ui-aux0] set authentication password simple aabbcc 
After the configuration, when a user logs in to the switch through the console port, the user must enter 
the correct password. 
z  Example of the scheme authentication mode configuration 
# Configure the authentication mode as scheme for VTY users logging in through Telnet. 
<Sysname> system-view 
System View: return to User View with Ctrl+Z. 
[Sysname] user-interface vty 0 
[Sysname-ui-vty0] authentication-mode scheme 
[Sysname-ui-vty0] quit 
# Specify domain system as the default domain, and set the scheme authentication mode to local for 
the domain. 
[Sysname] domain default enable system 
[Sysname] domain system 
[Sysname-isp-system] scheme local 
[Sysname-ui-vty0] quit 
# Configure the local authentication username and password. 
[Sysname] local-user guest 
[Sysname-luser-guest] password simple 123456 
[Sysname-luser-guest] service-type telnet level 2 
After the configuration, when a user logs in to the switch through VTY0, the user must enter the 
configured username and password.