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abbetechFlag for United States of America

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Can't copy router configs with TFTP

Why can't this router write back? Some can and some of them do this... what am I over looking? I creates a empty file but times out. I have no trouble getting the switches to copy over from the other subnets, why?

Example:
13-Router-1#copy running-config tftp
Address or name of remote host []? 10.3.50.153
Destination filename [13-router-1-confg]?
.....
%Error opening tftp://10.3.50.153/13-router-1-confg (Timed out)
13-Router-1#copy running-config tftp
Address or name of remote host []? 10.3.50.153
Destination filename [13-router-1-confg]?
.....
%Error opening tftp://10.3.50.153/13-router-1-confg (Timed out)
13-Router-1#


Regards,
ABBEtech
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Ken Boone
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Can the router ping 10.3.50.153?

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ASKER

No, put I can telnet into the router from that IP address...
Ok so when the router generates an IP packet where he is the source ip address i.e. ping from the router, telnet from the router, tftp from the router... the router will use the source ip address of the interface in which the router will send that packet out.  In other words if you have 5 interfaces all with ip addresses on the router and the router attempts to tftp a config to 10.3.50.153, if the router determines it needs to send the packet out interface 3 to reach 10.3.50.153, then the router will use the source ip address in the tftp packet from interface 3.  

You can override this behavior with the following command:

ip tftp source-address "interface"

There could also be access-lists blocking this traffic.  tftp is udp port 69.  Is the traffic going through a firewall perhaps?

What I would do is issue an extended ping from the router to 10.3.50.153.

When you issue an extended ping, just type ping and hit enter.

Accept the defaults for most arguements while specifying 10.3.50.153 as the destination.

When you get to the field that says extended commands(Y/N) hit Y

Then take the defaults for everything except the source interface.  for this field use the ip address that you use when you telnet to the router.  then take the defaults for everything else.  

Does this ping work?  If so use the ip tftp sourc-interface command to specify that particular interface and you should be good.
I'll give it a try but I'm still confused as to why the switches at that branch can send there config file through the router and back to that ip but the router can't?
Well let me know the results of those steps and we will see where it takes us.
Are you using a Windows OS on the computer you have installed the TFTP server on? you may need to allow the program through the windows firewall.
Agree with kenboonejr - if you can telnet to the router but you can't ping the device from the router that suggests a firewall issue.  However, you say that you can TFTP software from other switches to the device at 10.3.50.153, so I'd say there's an ACL on the router.

Can you provide config snippet from your router?
Which router? The one I'm trying to copy the configuration from is attached. It's not a windows firewall issue.
Router.txt
What ip address do you telnet to when you hit the router?
10.3.13.1
13-Router-1#ping
Protocol [ip]: 10.3.50.153
% Unknown protocol - "10.3.50.153", type "ping ?" for help
13-Router-1#




When you type ping and hit enter it is asking you first what protocol with a default of IP.  Just hit enter there then it will ask you for the destination ip address.
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Ken Boone
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Thanks!