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7  Specifying Source for Telnet Packets 
When specifying source IP address/interface for Telnet packets, go to these sections for information 
you are interested in: 
z  Introduction 
z  Specifying Source IP address/Interface for Telnet Packets 
z  Displaying the source IP address/Interface Specified for Telnet Packets 
Introduction 
To improve security and make it easier to manage services, you can specify source IP 
addresses/interfaces for Telnet clients. 
Usually, VLAN interface IP addresses and Loopback interface IP addresses are used as the source IP 
addresses of Telnet packets. After you specify the IP address of a VLAN interface or a Loopback 
interface as the source IP address of Telnet packets, all the packets exchanged between the Telnet 
client and the Telnet server use the IP address as their source IP addresses, regardless of the ports 
through which they are transmitted. In such a way, the actual IP addresses used are concealed. This 
helps to improve security. Specifying source IP address/interfaces for Telnet packets also provides a 
way to successfully connect to servers that only accept packets with specific source IP addresses. 
Specifying Source IP address/Interface for Telnet Packets 
The configuration can be performed in user view and system view. The configuration performed in user 
view only applies to the current session. Whereas the configuration performed in system view applies 
to all the subsequent sessions. Priority in user view is higher than that in system view. 
Specifying source IP address/interface for Telnet packets in user view 
Follow these steps to specify source IP address/interface for Telnet packets in user view: 
To do…  Use the command…  Remarks 
Specify source IP 
address/interface for Telnet 
packets (the switch operates 
as a Telnet client) 
telnet remote-system 
[ port-number ] [ source { ip 
ip-address | interface 
interface-type 
interface-number } ] 
Optional 
By default, no source IP 
address/interface is specified. 
 
Specifying source IP address/interface for Telnet packets in system view 
Follow these steps to specify source IP address/interface for Telnet packets in system view: 
To do…  Use the command…  Remarks 
Enter system view  system-view —