3-10# Configure to authenticate users logging in to VTY 0 in the scheme mode.[Sysname-ui-vty0] authentication-mode scheme# Configure Telnet protocol is supported.[Sysname-ui-vty0] protocol inbound telnet# Set the maximum number of lines the screen can contain to 30.[Sysname-ui-vty0] screen-length 30# Set the maximum number of commands the history command buffer can store to 20.[Sysname-ui-vty0] history-command max-size 20# Set the timeout time to 6 minutes.[Sysname-ui-vty0] idle-timeout 6z Configure the authentication schemeConfigure the authentication server by referring to related parts in AAA Configuration.Logging In Through SSHSecure Shell (SSH) offers an approach to logging into a remote device securely. With encryption andstrong authentication, it protects devices against attacks such as IP spoofing and plain text passwordinterception. For the security features provided by SSH, see SSH Configuration in the Security Volume.Configuring Command AuthorizationBy default, command level for a login user depends on the user level. The user is authorized thecommand with the default level not higher than the user level. With the command authorizationconfigured, the command level for a login user is decided by both the user level and AAA authorization.If a user executes a command of the corresponding user level, the authorization server checks whetherthe command is authorized. If yes, the command can be executed.The authorization server checks the commands authorized for users through the username, and thusthe command authorization configuration involves three steps:1) Configure to use username and password authentication when users log in.2) Enable command authorization. See the following table for details.3) Configure an authorization scheme. Specify the IP address and other related parameters for theaccounting server. For details, refer to the AAA Configuration in the Security Volume.Follow these steps to enable command authorization:To do… Use the command… RemarksEnter system view system-view —Enter AUX user interface view user-interface vty first-number[ last-number ] —Enable command authorization command authorizationRequiredDisabled by default, that is,users can execute commandswithout authorization.
