Cisco IOS Cookbook, 2nd Edition

Using the Router as a TFTP Server

Problem

You want to configure your router to act as a TFTP server.

Solution

The tftp-server command configures the router to act as a TFTP server:

Router1#configure terminal 
Enter configuration commands, one per line.  End with CNTL/Z.
Router1(config)#tftp-server flash:c2600-ik9o3s-mz.122-12a.bin
Router1(config)#end
Router1#

Discussion

The ability to use a router as a TFTP server can be quite useful. We have often used this feature to upgrade several routers that are separated from the TFTP server by slow WAN connections. In situations like this, you can upgrade one of the remote routers by using TFTP over the slow WAN connection as we described in Recipe 1.6. Then you can configure the first router to act as a TFTP server, and use it to upgrade the remaining routers over high-speed local links.

The router is not a fully functional TFTP server. It can only serve files for download. You cannot use this feature to upload files into the serving router’s local flash. However, the router is not limited to just serving IOS images. You can use your router’s flash to store configuration files and make them available for download via TFTP as well. Moreover, you can even use it to hold configuration files for nonCisco equipment.

Security is a concern whenever you enable services on a router. Every extra service you enable provides the wily hacker with a new potential avenue to exploit against your network. Therefore, we certainly don’t recommend using the TFTP server ...