The first time you access the device, you can only log in to the CLI through the console port unless the device is automatically configured at startup. After login, you can change console login parameters or configure other access methods.

The device supports the FIPS mode that complies with NIST FIPS 140-2 requirements. Support for features, commands, and parameters might differ in FIPS mode and non-FIPS mode. For more information about FIPS mode, see Security Configuration Guide.

Telnet not supported in FIPS mode.

In login management related descriptions, it is assumed that the device does not enter the automatic configuration process at startup.

Using the console port for the first device access

About this task

Console login is the fundamental login method.

Prerequisites

To log in through the console port, prepare a console terminal, for example, a PC. Make sure the console terminal has a terminal emulation program, such as HyperTerminal or PuTTY. For information about how to use terminal emulation programs, see the programs' user guides.

Procedure

1. Turn off the PC.

The serial ports on PCs do not support hot swapping. Before connecting a cable to or disconnecting a cable from a serial port on a PC, you must turn off the PC.

2. Find the console cable shipped with the device and connect the DB-9 female connector of the console cable to the serial port of the PC.

3. Identify the console port of the device carefully and connect the RJ-45 connector of the console cable to the console port.

IMPORTANT:

To connect a PC to an operating device, first connect the PC end. To disconnect a PC from an operating device, first disconnect the device end.

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Figure 1 Connecting a terminal to the console port

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4. Turn on the PC.

5. On the PC, launch the terminal emulation program, and create a connection that uses the serial port connected to the device. Set the port properties so the port properties match the following console port default settings:

¡ Bits per second—9600 bps.

¡ Flow control—None.

¡ Parity—None.

¡ Stop bits—1.

¡ Data bits—8.

6. Power on the device and press Enter as prompted.

The user view prompt appears. You can enter commands to configure or manage the device. To get help, enter a question mark (?).

Configuring CLI login

About CLI login

The device uses user lines (also called user interfaces) to manage CLI sessions and monitor user behavior. For a user line, you can configure access control settings, including the login authentication method and user roles.

User lines

User line types

The device supports the types of user lines listed in Table 1. Different user lines require different login methods.

Table 1 CLI login method and user line matrix

User line	Login method
Console line	Console port.
Virtual type terminal (VTY) line	Telnet or SSH.

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User line numbering

A user line has an absolute number and a relative number.

An absolute number uniquely identifies a user line among all user lines. The user lines are numbered starting from 0 and incrementing by 1, in the sequence of console and VTY lines. You can use the display line command without any parameters to view supported user lines and their absolute numbers.

A relative number uniquely identifies a user line among all user lines of the same type. The number format is user line type + number. All types of user lines are numbered starting from 0 and incrementing by 1. For example, the first VTY line is VTY 0.

User line assignment

The device assigns user lines to CLI login users depending on their login methods, as shown in Table 1. When a user logs in, the device checks the idle user lines for the login method, and assigns the lowest numbered user line to the user. For example, if VTY 0 and VTY 3 are idle when a user Telnets to the device, the device assigns VTY 0 to the user.

Each user line can be assigned only to one user at a time. If no user line is available, a CLI login attempt will be rejected.

Login authentication modes

You can configure login authentication to prevent illegal access to the device CLI.

In non-FIPS mode, the device supports the following login authentication modes:

· None—Disables authentication. This mode allows access without authentication and is insecure.

· Password—Requires password authentication. A user must provide the correct password at login.

· Scheme—Uses the AAA module to provide local or remote login authentication. A user must provide the correct username and password at login.

In FIPS mode, the device supports only the scheme authentication mode.

Different login authentication modes require different user line configurations, as shown in Table 2.

Table 2 Configuration required for different login authentication modes

Authentication mode	Configuration tasks
None	Set the authentication mode to none.
Password	1. Set the authentication mode to password. 2. Set a password.
Scheme	3. Set the authentication mode to scheme. 4. Configure login authentication methods in ISP domain view. For more information, see AAA in User Access and Authentication Configuration Guide.
Scheme

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User roles

A user is assigned user roles at login. The user roles control the commands available for the user. For more information about user roles, see "Configuring RBAC."

The device assigns user roles based on the login authentication mode and user type.

· In none or password authentication mode, the device assigns the user roles specified for the user line.

· In scheme authentication mode, the device uses the following rules to assign user roles:

¡ For an SSH login user who uses publickey or password-publickey authentication, the device assigns the user roles specified for the local device management user with the same name.

¡ For other users, the device assigns user roles according to the user role configuration of the AAA module. If the AAA server does not assign any user roles and the default user role feature is disabled, a remote AAA authentication user cannot log in.

FIPS compliance

Telnet login is not supported in FIPS mode.

Restrictions and guidelines: CLI login configuration

For commands that are available in both user line view and user line class view, the following rules apply:

· A setting in user line view applies only to the user line. A setting in user line class view applies to all user lines of the class.

· A non-default setting in either view takes precedence over the default setting in the other view. A non-default setting in user line view takes precedence over the non-default setting in user line class view.

· A setting in user line class view takes effect only on users who log in after the setting is made. It does not affect users who are already online when the setting is made.

Configuring console login

About console and AUX login

You can connect a terminal to the console port of the device to log in and manage the device, as shown in Figure 2. For information about the login procedure, see "Using the console port for the first device access."

Figure 2 Logging in through the console port

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By default, console login is enabled and does not require authentication. The default user role is network-admin for a console user. To improve device security, configure password or scheme authentication for console login immediately after you log in to the device for the first time.

Restrictions and guidelines

A console login configuration change takes effect only on users who log in after the change is made. It does not affect users who are already online when the change is made.

In FIPS mode, the device supports only scheme authentication. You cannot disable authentication or configure password authentication.

The device displays the current memory usage if the following conditions exist:

1. The memory-threshold command is used to configure free-memory thresholds.

2. The system monitors that the free memory size has decreased to or below the configured minor, severe, critical, or early-warning alarm threshold.

3. The user logs in to the management interface of the device through the console port.

Console login configuration tasks at a glance

To configure console login, perform the following tasks:

1. Configuring console login authentication

¡ Disabling authentication for console login

¡ Configuring password authentication for console login

¡ Configuring scheme authentication for console login

2. (Optional.) Configuring common console login settings

Configuring console login authentication

Disabling authentication for console login

1. Enter system view.

system-view

2. Enter console line view or class view.

¡ Enter console line view.

line console first-number [ last-number ]

¡ Enter console line class view.

line class console

3. Disable authentication.

authentication-mode none

By default, authentication is disabled for console login.

CAUTION:

When authentication is disabled, users can log in to the device through the line or line class without authentication. For security purpose, disable authentication with caution.

4. Assign a user role.

user-role role-name

By default, a console user is assigned the network-admin user role.

Configuring password authentication for console login

1. Enter system view.

system-view

2. Enter console line view or class view.

¡ Enter console line view.

line console first-number [ last-number ]

¡ Enter console class view.

line class console

3. Enable password authentication.

authentication-mode password

By default, authentication is disabled for console login.

4. Set a password.

set authentication password { hash | simple } password

By default, no password is set.

5. Assign a user role.

user-role role-name

By default, a console user is assigned the network-admin user role.

Configuring scheme authentication for console login

1. Enter system view.

system-view

2. Enter console line view or class view.

¡ Enter console line view.

line console first-number [ last-number ]

¡ Enter console line class view.

line class console

3. Enable scheme authentication.

In non-FIPS mode:

authentication-mode scheme

By default, authentication is disabled for console login.

In FIPS mode:

authentication-mode scheme

By default, scheme authentication is enabled.

IMPORTANT:

When you enable scheme authentication, make sure an authentication user account is available. If no authentication user account is available, you cannot log in to the device through the line or line class at the next time.

4. Configure user authentication parameters in ISP domain view.

To use local authentication, configure a local user and set the relevant attributes. To use remote authentication, configure a RADIUS, LDAP, or HWTACACS scheme. For more information, see AAA in User Access and Authentication Configuration Guide.

Configuring common console login settings

Restrictions and guidelines

Some common console login settings take effect immediately and can interrupt the current session. Use a login method different from console login to log in to the device before you change console login settings.

After you change console login settings, adjust the settings on the configuration terminal accordingly for a successful login.

Procedure

1. Enter system view.

system-view

2. Enter console line view or class view.

¡ Enter console line view.

line console first-number [ last-number ]

¡ Enter console line class view.

line class console

3. Configure transmission parameters.

¡ Set the transmission rate.

speed speed-value

By default, the transmission rate is 9600 bps.

This command is not available in user line class view.

¡ Specify the parity mode.

parity { even | mark | none | odd | space }

By default, a user line does not use parity.

This command is not available in user line class view.

¡ Configure flow control.

flow-control { hardware | none | software }

By default, the device does not perform flow control.

This command is not available in user line class view.

¡ Specify the number of data bits for a character.

databits { 7 | 8 }

The default is 8.

This command is not available in user line class view.

Parameter	Description
7	Uses standard ASCII characters.
8	Uses extended ASCII characters.

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¡ Specify the number of stop bits for a character.

stopbits { 1 | 1.5 | 2 }

The default is 1.

Stop bits indicate the end of a character. The more the stop bits, the slower the transmission.

This command is not available in user line class view.

4. Configure terminal attributes.

¡ Enable the terminal service.

shell

Be default, the terminal service is enabled on all user lines.

The undo shell command is not available in console line view.

¡ Specify the terminal display type.

terminal type { ansi | vt100 }

By default, the terminal display type is ANSI.

The device supports ANSI and VT100 terminal display types. As a best practice, specify VT100 type on both the device and the configuration terminal. You can also specify the ANSI type for both sides, but a display problem might occur if a command line has more than 80 characters.

¡ Set the maximum number of lines of command output to send to the terminal at a time.

screen-length screen-length

By default, the device sends a maximum of 24 lines to the terminal at a time.

To disable pausing between screens of output, set the value to 0.

¡ Set the size for the command history buffer.

history-command max-size value

By default, the buffer size is 10. The buffer for a user line can save a maximum of 10 history commands.

¡ Set the CLI connection idle-timeout timer.

idle-timeout minutes [ seconds ]

By default, the CLI connection idle-timeout timer is 10 minutes.

If no interaction occurs between the device and the user within the idle-timeout interval, the system automatically terminates the user connection on the user line.

If you set the timeout timer to 0, the connection will not be aged out.

5. Specify the command to be automatically executed for login users on the lines.

auto-execute command command

By default, no command is specified for auto execution.

CAUTION:

Use this command with caution. If this command is used on a user line, users that log in to the device through this user line might fail to configure the system.

The device will automatically execute the specified command when a user logs in through the user line, and close the user connection after the command is executed.

This command is not available in console line view or console line class view.

6. Configure shortcut keys.

¡ Specify the terminal session activation key.

activation-key character

By default, pressing Enter starts the terminal session.

¡ Specify the escape key.

escape-key { character | default }

By default, pressing Ctrl+C terminates a command.

¡ Set the user line locking key.

lock-key key-string

By default, no user line locking key is set.

Configuring Telnet login

About Telnet login

The device can act as a Telnet server to allow Telnet login, or as a Telnet client to Telnet to other devices.

Restrictions and guidelines

Telnet login is not supported in FIPS mode. For more information about FIPS mode, see Security Configuration Guide.

A Telnet login configuration change takes effect only on users who log in after the change is made. It does not affect users who are already online when the change is made.

The device displays the current memory usage if the following conditions exist:

1. The memory-threshold command is used to configure free-memory thresholds.

2. The system monitors that the free memory size has decreased to or below the configured minor, severe, critical, or early-warning alarm threshold.

3. The user Telnets to the device.

Configuring the device as a Telnet server

Telnet server configuration tasks at a glance

To configure the device as a Telnet server, perform the following tasks:

1. Enabling the Telnet server

2. Configuring Telnet login authentication

¡ Disabling authentication for Telnet login

¡ Configuring password authentication for Telnet login

¡ Configuring scheme authentication for Telnet login

3. (Optional.) Configuring common Telnet server settings

4. (Optional.) Configuring common VTY line settings

Enabling the Telnet server

1. Enter system view.

system-view

2. Enable the Telnet server.

telnet server enable

By default, the Telnet server is disabled.

Disabling authentication for Telnet login

1. Enter system view.

system-view

2. Enter VTY line view or class view.

¡ Enter VTY line view.

line vty first-number [ last-number ]

¡ Enter VTY line class view.

line class vty

3. Disable authentication.

authentication-mode none

By default, password authentication is enabled for Telnet login.

CAUTION:

When authentication is disabled, users can log in to the device through the line or line class without authentication. For security purpose, disable authentication with caution.

In VTY line view, this command is associated with the protocol inbound command. If one command has a non-default setting in VTY line view, the other command uses its setting in VTY line view, regardless of its setting in VTY line class view.

4. (Optional.) Assign a user role.

user-role role-name

By default, a VTY line user is assigned the network-operator user role.

Configuring password authentication for Telnet login

1. Enter system view.

system-view

2. Enter VTY line view or class view.

¡ Enter VTY line view.

line vty first-number [ last-number ]

¡ Enter VTY line class view.

line class vty

3. Enable password authentication.

authentication-mode password

By default, password authentication is enabled for Telnet login.

CAUTION:

When you enable password authentication, you must also configure an authentication password for the line or line class. If no authentication password is configured, you cannot log in to the device through the line or line class at the next time.

4. Set a password.

set authentication password { hash | simple } password

By default, no password is set.

5. (Optional.) Assign a user role.

user-role role-name

By default, a VTY line user is assigned the network-operator user role.

Configuring scheme authentication for Telnet login

1. Enter system view.

system-view

2. Enter VTY line view or class view.

¡ Enter VTY line view.

line vty first-number [ last-number ]

¡ Enter VTY line class view.

line class vty

3. Enable scheme authentication.

authentication-mode scheme

By default, password authentication is enabled for Telnet login.

CAUTION:

4. Configure user authentication parameters in ISP domain view.

To use local authentication, configure a local user and set the relevant attributes.

To use remote authentication, configure a RADIUS, LDAP, or HWTACACS scheme. For more information, see AAA in User Access and Authentication Configuration Guide.

Config uring the alarm threshold and alarm clearance threshold for Telnet login failures

1. Enter system view.

system-view

2. Set the alarm threshold and alarm clearance threshold for Telnet login failures in a statistics period.

telnet server login-failed threshold-alarm upper-limit report-times lower-limit resume-times period period-time

By default, the statistics period is five minutes and the alarm threshold and alarm clearance threshold for Telnet login failures in the statistics period is 30 and 20, respectively.

After you execute this command, if the number of Telnet login failures reaches the alarm threshold in a statistics period, an alarm message is generated. If the number of Telnet login failures drops below the alarm clearance threshold in a statistics period, an alarm clearance message is generated. This helps you obtain real-time information about Telnet logins.

Configuring common Telnet server settings

1. Enter system view.

system-view

2. Set the DSCP value for outgoing Telnet packets.

IPv4:

telnet server dscp dscp-value

IPv6:

telnet server ipv6 dscp dscp-value

By default, the DSCP value is 48. The DSCP value is carried in the ToS field of an IPv4 packet and in the Traffic class field of an IPv6 packet to indicate the packet transmission priority.

3. Specify the Telnet service port number.

IPv4:

telnet server port port-number

IPv6:

telnet server ipv6 port port-number

By default, the Telnet service port number is 23.

4. Set the maximum number of concurrent Telnet users.

aaa session-limit telnet max-sessions

By default, the maximum number of concurrent Telnet users is 32.

Changing this setting does not affect users who are currently online. If the new limit is less than the number of online Telnet users, no additional users can Telnet in until the number drops below the new limit.

For more information about this command, see User Access and Authentication Command Reference.

Configuring common VTY line settings

1. Enter system view.

system-view

2. Enter VTY line view or class view.

¡ Enter VTY line view.

line vty first-number [ last-number ]

¡ Enter VTY line class view.

line class vty

3. Configure VTY terminal attributes.

¡ Enable the terminal service.

shell

By default, the terminal service is enabled on all user lines.

¡ Specify the terminal display type.

terminal type { ansi | vt100 }

By default, the terminal display type is ANSI.

¡ Set the maximum number of lines of command output to send to the terminal at a time.

screen-length screen-length

By default, the device sends a maximum of 24 lines to the terminal at a time.

To disable pausing between screens of output, set the value to 0.

¡ Set the size for the command history buffer.

history-command max-size value

By default, the buffer size is 10. The buffer for a user line can save a maximum of 10 history commands.

¡ Set the CLI connection idle-timeout timer.

idle-timeout minutes [ seconds ]

By default, the CLI connection idle-timeout timer is 10 minutes.

If no interaction occurs between the device and the user within the idle-timeout interval, the system automatically terminates the user connection on the user line.

If you set the timeout timer to 0, the connection will not be aged out.

4. Specify the supported protocols.

protocol inbound { all | pad | ssh | telnet }

By default, Telnet and SSH are supported.

A protocol change takes effect only on users who log in after the setting is made. It does not affect users who are already online when the setting is made.

In VTY line view, this command is associated with the authentication-mode command. If one command has a non-default setting in VTY line view, the other command uses its setting in VTY line view, regardless of its setting in VTY line class view.

5. Specify the command to be automatically executed for login users on the user lines.

auto-execute command command

By default, no command is specified for auto execution.

IMPORTANT:

Before you execute this command and save the configuration, make sure you can access the CLI to modify the configuration through other VTY lines or console lines.

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For a VTY line, you can specify a command that is to be automatically executed when a user logs in. After executing the specified command, the system automatically disconnects the Telnet session.

6. Configure shortcut keys.

¡ Specify the shortcut key for terminating a task.

escape-key { character | default }

The default setting is Ctrl+C.

¡ Set the user line locking key.

lock-key key-string

By default, no user line locking key is set.

Using the device to log in to a Telnet server

About this task

You can use the device as a Telnet client to log in to a Telnet server.

Figure 3 Telnetting from the device to a Telnet server

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Prerequisites

Assign an IP address to the device and obtain the IP address of the Telnet server. If the device resides on a different subnet than the Telnet server, make sure the device and the Telnet server can reach each other.

Procedure

1. Enter system view.

system-view

2. (Optional.) Specify the source IPv4 address or source interface for outgoing Telnet packets.

telnet client source { interface interface-type interface-number | ip ip-address }

By default, no source IPv4 address or source interface is specified. The device uses the primary IPv4 address of the output interface as the source address for outgoing Telnet packets.

3. Return to user view.

quit

4. Use the device to log in to a Telnet server.

IPv4:

telnet remote-host [ service-port ] [ vpn-instance vpn-instance-name ] [ source { interface interface-type interface-number | ip ip-address } | dscp dscp-value ] * [ escape character ]

IPv6:

telnet ipv6 remote-host [ -i interface-type interface-number ] [ port-number ] [ vpn-instance vpn-instance-name ] [ source { interface interface-type interface-number | ipv6 ipv6-address } | dscp dscp-value ] * [ escape character ]

Configuring SSH login

About SSH login

SSH offers a secure remote login method. By providing encryption and strong authentication, it protects devices against attacks such as IP spoofing and plaintext password interception. For more information, see SSH in Security Configuration Guide.

The device can act as an SSH server to allow Telnet login, or as an SSH client to log in to an SSH server.

Configuring the device as an SSH server

About this task

This section provides the SSH server configuration procedure used when the SSH client authentication method is password. For more information about SSH and publickey authentication configuration, see SSH in Security Configuration Guide.

Procedure

1. Enter system view.

system-view

2. Create local key pairs.

In non-FIPS mode:

public-key local create { dsa | ecdsa [ secp192r1 | secp256r1 | secp384r1 | secp521r1 ] | rsa } [ name key-name ]

In FIPS mode:

public-key local create { dsa | ecdsa [ secp256r1 | secp384r1 | secp521r1 ] | rsa } [ name key-name ]

3. Enable the SSH server.

ssh server enable

By default, the SSH server is disabled.

4. (Optional.) Create an SSH user and specify the authentication mode.

ssh user username service-type stelnet authentication-type password

5. Enter VTY line view or class view.

¡ Enter VTY line view.

line vty first-number [ last-number ]

¡ Enter VTY line class view.

line class vty

6. Enable scheme authentication.

In non-FIPS mode:

authentication-mode scheme

By default, password authentication is enabled for VTY lines.

CAUTION:

In FIPS mode:

authentication-mode scheme

By default, scheme authentication is enabled for VTY lines.

7. (Optional.) Specify the protocols for the user lines to support.

In non-FIPS mode:

protocol inbound { all | pad | ssh | telnet }

By default, Telnet and SSH are supported.

A protocol change takes effect only on users who log in after the setting is made. It does not affect users who are already online when the setting is made.

In FIPS mode:

protocol inbound ssh

By default, SSH is supported.

A protocol change takes effect only on users who log in after the setting is made. It does not affect users who are already online when the setting is made.

8. (Optional.) Set the maximum number of concurrent SSH users.

aaa session-limit ssh max-sessions

By default, the maximum number of concurrent SSH users is 32.

Changing this setting does not affect users who are currently online. If the new limit is less than the number of online SSH users, no additional SSH users can log in until the number drops below the new limit.

For more information about this command, see User Access and Authentication Command Reference.

9. (Optional.) Configure common settings for VTY lines:

a. Return to system view.

quit

b. Configure common settings for VTY lines.

See "Configuring common VTY line settings."

Using the device to log in to an SSH server

About this task

You can use the device as an SSH client to log in to an SSH server.

Figure 4 Logging in to an SSH server from the device

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Prerequisites

Assign an IP address to the device and obtain the IP address of the SSH server. If the device resides on a different subnet than the SSH server, make sure the device and the SSH server can reach each other.

Procedure

To use the device to log in to an SSH server, execute one of the following commands in user view:

IPv4:

ssh2 server

IPv6:

ssh2 ipv6 server

To work with the SSH server, you might need to specify a set of parameters. For more information, see Security Configuration Guide.

Verifying and maintaining CLI login

Displaying user line configuration and operating status

Perform display tasks in any view.

· Display user line information.

display line [ num1 | { console | vty } num2 ] [ summary ]

· Display online CLI users.

display users [ all ]

Sending messages to user lines

To send messages to user lines, execute the following command in user view:

send { all | num1 | { console | vty } num2 }

Releasing user lines

About this task

Multiple users can log in to the device to simultaneously configure the device. When necessary, you can execute this command to release some user connections.

Restrictions and guidelines

You cannot use this command to release the connection you are using.

This command is not supported in FIPS mode.

Procedure

To release user lines, execute the following command in user view:

free line { num1 | { console | vty } num2 }

Locking the current user line

About this task

You can lock the current user line to prevent unauthorized users from using the line.

Procedure

Perform lock tasks in user view.

· Lock the current user line and set the password for unlocking the line.

lock

This command is not supported in FIPS mode.

To unlock the locked user line, you must press Enter and provide the password you set.

· Lock the current user line and enable unlocking authentication.

lock reauthentication

To unlock the locked user line, you must press Enter and provide the login password to pass reauthentication.

Displaying Telnet client settings

To display Telnet client settings, execute the following command in any view:

display telnet client

Controlling user access to the device

About login user access control

Use ACLs to prevent unauthorized access, and configure command authorization and accounting to monitor and control user behavior.

To control user access, specify an ACL that has rules so that only users permitted by the ACL can access the device.

· If no ACL is applied, all users can access the device.

· If the ACL for Telnet, SSH, or SNMP access control does not exist or does not have rules, no Telnet, SSH, or SNMP users can access the device.

· If a VPN instance is specified in an ACL rule, the rule applies only to the packets of the VPN instance. If no VPN instance is specified in an ACL rule, the rule applies only to the packets on the public network.

For more information about ACLs, see ACL and QoS Configuration Guide.

FIPS compliance

Telnet not supported in FIPS mode.

Controlling Telnet and SSH logins

Controlling Telnet logins

1. Enter system view.

system-view

2. Apply an ACL to control Telnet logins.

IPv4:

telnet server acl { advanced-acl-number | basic-acl-number | mac mac-acl-number }

IPv6:

telnet server ipv6 acl { ipv6 { advanced-acl-number | basic-acl-number } | mac mac-acl-number }

By default, no ACL is used to control Telnet logins.

3. (Optional.) Enable logging for Telnet login attempts that are denied by the Telnet login control ACL.

telnet server acl-deny-log enable

By default, logging is disabled for Telnet login attempts that are denied by the Telnet login control ACL.

Controlling SSH logins

1. Enter system view.

system-view

2. Apply an ACL to control SSH logins.

IPv4:

ssh server acl { advanced-acl-number | basic-acl-number | mac mac-acl-number }

IPv6:

ssh server ipv6 acl { ipv6 { advanced-acl-number | basic-acl-number } | mac mac-acl-number }

By default, no ACL is used to control SSH logins.

3. (Optional.) Enable logging for SSH login attempts that are denied by the SSH login control ACL.

ssh server acl-deny-log enable

By default, logging is disabled for SSH login attempts that are denied by the SSH login control ACL.

For more information about ssh commands, see Security Command Reference.

Example: Controlling Telnet login

Network configuration

As shown in Figure 5, the device is a Telnet server.

Configure the device to permit only Telnet packets sourced from Host A and Host B.

Figure 5 Network diagram

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Procedure

# Configure an ACL to permit packets sourced from Host A and Host B.

<Sysname> system-view

[Sysname] acl basic 2000 match-order config

[Sysname-acl-ipv4-basic-2000] rule 1 permit source 10.110.100.52 0

[Sysname-acl-ipv4-basic-2000] rule 2 permit source 10.110.100.46 0

[Sysname-acl-ipv4-basic-2000] quit

# Apply the ACL to filter Telnet logins.

[Sysname] telnet server acl 2000

Configuring command authorization

About command authorization

By default, commands available for a user depend only on the user's user roles. When the authentication mode is scheme, you can configure the command authorization feature to further control access to commands.

After you enable command authorization, a user can use only commands that are permitted by both the AAA scheme and user roles.

Restrictions and guidelines

The command authorization method can be different from the user login authorization method.

For the command authorization feature to take effect, you must configure a command authorization method in ISP domain view. For more information, see AAA in User Access and Authentication Configuration Guide.

For the command authorization feature to take effect, you must also set the authentication mode for device login to scheme. If the authentication mode is none or password, command authorization will not take effect after you enable command authorization.

Procedure

1. Enter system view.

system-view

2. Enter user line view or user line class view.

¡ Enter user line view.

line { first-number1 [ last-number1 ] | { console | vty } first-number2 [ last-number2 ] }

¡ Enter user line class view.

line class { console | vty }

A setting in user line view applies only to the user line. A setting in user line class view applies to all user lines of the class. A non-default setting in either view takes precedence over the default setting in the other view. A non-default setting in user line view takes precedence over the non-default setting in user line class view.

A setting in user line class view takes effect only on users who log in after the setting is made. It does not affect users who are already online when the setting is made.

3. Enable scheme authentication.

In non-FIPS mode:

authentication-mode scheme

By default, authentication is disabled for console login.

In FIPS mode:

authentication-mode scheme

By default, scheme authentication is enabled.

CAUTION:

4. Enable command authorization.

command authorization

By default, command authorization is disabled, and the commands available for a user only depend on the user role.

If the command authorization command is executed in user line class view, command authorization is enabled on all user lines in the class. You cannot execute the undo command authorization command in the view of a user line in the class.

Example: Configuring command authorization

Network configuration

As shown in Figure 6, Host A needs to log in to the device to manage the device.

Configure the device to perform the following operations:

· Allow Host A to Telnet in after authentication.

· Use the HWTACACS server to control the commands that the user can execute.

· If the HWTACACS server is not available, use local authorization.

Figure 6 Network diagram

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Prerequisites

Assign IP addresses to relevant interfaces. Make sure the device and the HWTACACS server can reach each other. Make sure the device and Host A can reach each other.

Procedure

# Enable the Telnet server.

<Device> system-view

[Device] telnet server enable

# Enable scheme authentication for user lines VTY 0 through VTY 4.

[Device] line vty 0 4

[Device-line-vty0-4] authentication-mode scheme

# Enable command authorization for the user lines.

[Device-line-vty0-4] command authorization

[Device-line-vty0-4] quit

# Create HWTACACS scheme tac.

[Device] hwtacacs scheme tac

# Configure the scheme to use the HWTACACS server at 192.168.2.20:49 for authentication and authorization.

[Device-hwtacacs-tac] primary authentication 192.168.2.20 49

[Device-hwtacacs-tac] primary authorization 192.168.2.20 49

# Set the shared keys to expert.

[Device-hwtacacs-tac] key authentication simple expert

[Device-hwtacacs-tac] key authorization simple expert

# Remove domain names from usernames sent to the HWTACACS server.

[Device-hwtacacs-tac] user-name-format without-domain

[Device-hwtacacs-tac] quit

# Configure the system-defined domain (system).

[Device] domain system

# Use HWTACACS scheme tac for login user authentication and command authorization. Use local authentication and local authorization as the backup method.

[Device-isp-system] authentication login hwtacacs-scheme tac local

[Device-isp-system] authorization command hwtacacs-scheme tac local

[Device-isp-system] quit

# Create local user monitor. Set the simple password to hello12345, the service type to Telnet, and the default user role to level-1.

[Device] local-user monitor

[Device-luser-manage-monitor] password simple hello12345

[Device-luser-manage-monitor] service-type telnet

[Device-luser-manage-monitor] authorization-attribute user-role level-1

Configuring command accounting

About command accounting

Command accounting uses the HWTACACS server to record all executed commands to monitor user behavior on the device.

If command accounting is enabled but command authorization is not, every executed command is recorded. If both command accounting and command authorization are enabled, only authorized commands that are executed are recorded.

Restrictions and guidelines

The command accounting method can be the same as or different from the command authorization method and user login authorization method.

For the command accounting feature to take effect, you must configure a command accounting method in ISP domain view. For more information, see AAA in User Access and Authentication Configuration Guide.

Procedure

1. Enter system view.

system-view

2. Enter user line view or user line class view.

¡ Enter user line view.

line { first-number1 [ last-number1 ] | { console | vty } first-number2 [ last-number2 ] }

¡ Enter user line class view.

line class { console | vty }

A setting in user line class view takes effect only on users who log in after the setting is made. It does not affect users who are already online when the setting is made.

3. Enable scheme authentication.

In non-FIPS mode:

authentication-mode scheme

By default, authentication is disabled for console login.

In FIPS mode:

authentication-mode scheme

By default, scheme authentication is enabled.

CAUTION:

4. Enable command accounting.

command accounting

By default, command accounting is disabled. The accounting server does not record the commands executed by users.

If the command accounting command is executed in user line class view, command accounting is enabled on all user lines in the class. You cannot execute the undo command accounting command in the view of a user line in the class.

Example: Configuring command accounting

Network configuration

As shown in Figure 7, users need to log in to the device to manage the device.

Configure the device to send commands executed by users to the HWTACACS server to monitor and control user operations on the device.

Figure 7 Network diagram

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Procedure

# Enable the Telnet server.

<Device> system-view

[Device] telnet server enable

# Enable command accounting for user line console 0.

[Device] line console 0

[Device-line-console0] command accounting

[Device-line-console0] quit

# Enable command accounting for user lines VTY 0 through VTY 63.

[Device] line vty 0 63

[Device-line-vty0-63] command accounting

[Device-line-vty0-63] quit

# Create HWTACACS scheme tac.

[Device] hwtacacs scheme tac

# Configure the scheme to use the HWTACACS server at 192.168.2.20:49 for accounting.

[Device-hwtacacs-tac] primary accounting 192.168.2.20 49

# Set the shared key to expert.

[Device-hwtacacs-tac] key accounting simple expert

# Remove domain names from usernames sent to the HWTACACS server.

[Device-hwtacacs-tac] user-name-format without-domain

[Device-hwtacacs-tac] quit

# Configure the system-defined domain (system) to use the HWTACACS scheme for command accounting.

[Device] domain system

[Device-isp-system] accounting command hwtacacs-scheme tac

[Device-isp-system] quit

Configuring character encodings

About character encodings

A character encoding is used to encode the characters in a character set into a specific binary number for storage. Each character in a character set corresponds to a unique binary code.

The device supports the GB18030 and UTF-8 encodings, which are available for both Chinese and English. GB18030 uses one byte and two bytes to encode English and Chinese characters, respectively, while UTF-8 uses one byte and three bytes. UTF-8 is an international encoding that contains all characters around the world, and can display correctly on the supported browsers. GB18030 saves more space for Chinese than UTF-8, but might display incorrectly because it is not universal.

Specifying character encodings

About this task

If the parameters to configure contain Chinese characters, make sure the login terminal and the device use the same character encoding. Otherwise, the configuration containing Chinese characters on the device might fail to be parsed correctly, or even fail to take effect.

This feature specifies the encoding for the configuration saved on the device, the default encoding for CLI terminals, and the encoding for SNMP clients. The character encoding for the system to save the configuration is the system encoding, which refers to the encoding transferred within the system. The encoding configuration on the device is to be encoded in the system encoding before being sent to the plug-in, and then is saved to the system configuration file. The default encoding of CLI terminals and the encoding of SNMP clients are user encodings, corresponding to COMSH user encoding and SNMP user encoding, respectively. Different console output needs to convert the system encoding into different user encodings.

Before configuring this feature, you can use display character-encoding to obtain current character encodings on the system and the login terminal.

Restrictions and guidelines

The character encoding settings on CLI terminals and SNMP clients take effect immediately and do not require a device reboot.

For a new character encoding to take effect on the system, reboot the device. Use the following restrictions and guidelines as needed:

· Before rebooting the device, use display | original-encoding to predict whether the configuration in the next start-up configuration file can be parsed correctly in the new character encoding. If a setting displays incorrectly, the setting cannot be parsed, and the new character encoding will cause the setting to fail to be restored after the reboot. To resolve this issue, you can configure another character encoding or use character-encoding again after the reboot.

· A new character encoding does not affect the character encodings that have already specified for the configuration files and log files. The new encoding will not automatically convert the configuration files and log files. You can use display | original-encoding to manually convert the files and save the converted files to a new configuration file.

· Before rebooting the device, you can use undo character-encoding to cancel the change to the system character encoding.

Procedure

1. Enter system view.

system-view

2. Specify a character encoding.

character-encoding system { gb18030 | utf-8 } cli-terminal { gb18030 | utf-8 } snmp { gb18030 | utf-8 }

By default, no character encoding is specified.

Specifying a character encoding for the current terminal

About this task

For Chinese characters to display correctly, make sure the login terminal and the system use the same character encoding.

Restrictions and guidelines

This feature makes sense only when the system character encoding is configured. You can use character-encoding to specify the system and terminal encodings. If you change the user encoding on the user interface, use terminal character-encoding to change the terminal encoding to keep user encoding and terminal encoding consistent. The terminal character-encoding command takes effect immediately.

Procedure

To specify a character encoding for the current terminal, execute the following command in user view:

terminal character-encoding { gb18030 | utf-8 }

By default, the character encoding for the current terminal is the same as the default encoding for the CLI.

Enabling character encoding check

About this task

This feature enables the device to examine the input characters for compliance with the configured character encoding. If the characters do not comply with the character encoding, the characters are blocked and an error message is returned.

Restrictions and guidelines

As a best practice, enable this feature. If this feature is disabled, the device does not examine any input characters for compliance with the configured character encoding, or block any characters. If the input characters do not comply with the character encoding, the configuration will not take effect.

Procedure

To enable character encoding check, execute the following command in user view:

character-encoding check

By default, character encoding check is enabled.

Verifying and maintaining character encoding configuration

Displaying the current character encoding on the device or login terminal

To display the current character encoding on the device or login terminal, execute the following command in any view:

display character-encoding [ terminal ]

Converting the command output into a character encoding

About this task

This feature enables the device to convert the output from the specified command to the specified encoding. It is mainly used to identify whether the current configuration or command output can be correctly parsed in a new character encoding. If the matching information cannot be correctly parsed, perform one of following operations:

· Modify the command lines that cannot be correctly parsed, and then reboot the device.

· Reboot the device for the new character encoding to take effect, and then modify the command lines that cannot be correctly parsed.

Procedure

To convert the output from a command in the system encoding into the character encoding on the current terminal, execute the following command in any view:

display command | original-encoding { gb18030 | utf-8 }

01-Fundamentals Configuration Guide

About this task

Prerequisites

Procedure

User line types

User line assignment

Disabling authentication for console login

Configuring password authentication for console login

Configuring scheme authentication for console login

Configuring common console login settings

Restrictions and guidelines

Procedure

Configuring Telnet login

About Telnet login

Configuring the device as a Telnet server

Telnet server configuration tasks at a glance

Configuring password authentication for Telnet login

Configuring scheme authentication for Telnet login

Configuring the alarm threshold and alarm clearance threshold for Telnet login failures

Configuring common VTY line settings

Using the device to log in to a Telnet server

About this task

Procedure

Configuring the device as an SSH server

About this task

Procedure

Using the device to log in to an SSH server

About this task

Prerequisites

Procedure

About this task

Restrictions and guidelines

Procedure

About this task

Procedure

Controlling Telnet and SSH logins

Example: Controlling Telnet login

Network configuration

Procedure

Network configuration

Prerequisites

Procedure

Network configuration

Procedure

About this task

Restrictions and guidelines

Procedure

About this task

Restrictions and guidelines

Procedure

About this task

Restrictions and guidelines

Procedure

About this task

Procedure

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Config uring the alarm threshold and alarm clearance threshold for Telnet login failures