Service Config - Error opening tftp://255.255.255.255

If you have worked on a newer Cisco IOS device, you may have seen the following error messages:

%Error opening tftp://255.255.255.255/network-confg (Socket error)
%Error opening tftp://255.255.255.255/cisconet.cfg (Socket error)
%Error opening tftp://255.255.255.255/router-confg (Socket error)
%Error opening tftp://255.255.255.255/ciscortr.cfg (Socket error)

If you are wondering what these messages mean, it is the result of the config service being enabled by default in some IOS versions. Read on to learn about how it works and how to disable it.

Service Config

The service config command does exactly what the log messages above imply, it causes the IOS device to try to load its config from a network server. This can be useful in certain circumstances, however in most cases it is an unnecessary feature and can safely be disabled.

To disable this feature, use the no service config command in global configuration mode:

Router>en
Router#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#no service config 
Router(config)#end
Router#wr
Building configuration...

*Feb 20 04:32:54.619: %SYS-5-CONFIG_I: Configured from console by console[OK]
Router#

It's that simple.

So, unless you are planning on using this feature and have a tftp server connected to your IOS device with configuration files at the ready, you may want to consider making "no service config" a part of your standard configuration across the network.

Reference: http://www.cisco.com/en/US/docs/ios/12_2/configfun/command/reference/frf...