The telnet ipv6 server-source command specifies a source IPv6 address for a Telnet server.
The undo telnet ipv6 server-source command cancels the specified source IPv6 address of a Telnet server.
By default, the source IPv6 address is ::.
telnet ipv6 server-source -a ipv6-address [ -vpn-instance vpn-instance-name ]
undo telnet ipv6 server-source
| Parameter | Description | Value |
|---|---|---|
-a ipv6-address |
Specifies the source IPv6 address for an Telnet server. |
The value is a 32-digit hexadecimal number, in the format of X:X:X:X:X:X:X:X. |
-vpn-instance vpn-instance-name |
Specifies the name of a VPN instance for an Telnet server. |
The value is a string of 1 to 31 case-sensitive characters, spaces and question marks are not supported. In addition, the VPN instance name must not be _public_. When double quotation marks are used around the string, spaces are allowed in the string. |
Usage Scenario
An Telnet server receives login requests from all IPv6 addresses, leading to low system security. To improve system security, you can run the telnet ipv6 server-source command to specify a source IPv6 address for the Telnet server. Then only authorized users can log in to the Telnet server.
Prerequisites
A VPN instance has been created before you run the command. Otherwise, the command cannot be executed.
Configuration Impact
If a source IPv6 address is specified for an Telnet server, the server allows Telnet users to log in through the specified source IPv6 address only, and denies access of Telnet users who attempt to log in through other IPv6 addresses. This configuration applies to the Telnet users who attempt to log in to the Telnet server, not to the Telnet users who have logged in to the server.
Precautions
If a source IPv6 address is specified for an Telnet server, Telnet users must be able to communicate with the specified source IPv6 address at Layer 3 to ensure that authorized Telnet users can log in to the Telnet server.
If the interface to which the specified source IPv6 address belongs is bound to a VPN instance, the -vpn-instance parameter must be specified when you specify the IPv6 address for the client.