Set the Telnet Source IP Address for a Cisco Router
Posted by Quinn McHenry in Cisco router
The default source IP address when telnetting from a Cisco router is that of the interface closest to the destination. Because some access lists may block traffic from the default IP address, it may be useful to temporarily or permanently set the telnet source IP address. This also helps test access lists.
To temporarily set the telnet source IP address for a single telnet session, use the /source-interface extension to the telnet command.
For example, to telnet to 192.168.1.4 using the source IP address of the interface FastEthernet0:
telnet 192.168.1.4 /source-interface FastEthernet0
To set this interface as the source IP address for all telnet sesions, use this command in configuration mode (conf t):
ip source-interface fastethernet0
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October 29, 2008 at 8:05 pm, great idea said:
Brilliant tip, got me out of a hole tonight!
May 19, 2010 at 2:17 pm, Mike said:
Anything similar for SSH?
December 08, 2010 at 8:34 pm, Richey said:
This command did not work on a box with 12.3. I used “ip telnet source-interface interface fa0/0″
March 25, 2011 at 1:51 pm, Satyadevan W said:
how to assign an ipaddress for auxiliary port in a router
October 02, 2011 at 11:23 am, mike said:
Thx dude