We have a 2911 router with an embedded switch that has the IOS on a Compact Flash Card. After configuring the router and the switch module, I save the running-config to the Flash Card.I do not write the config to NVRAM because when I turn off the router I want the configuration to be purged, due to security regulations. So everyday I insert the Compact flash card and boot the router. I connect a laptop via hyperterminal and then copy the config from the flash card to the startup-config and reload the router. This works, however is there a way that the router can boot from the configuration file on the Flash and it won't save the configuration into NVRAM? In other words, I would like to merely plug the Flash Card in and turn on the router and the configuration file is loaded.
Your answer was very helpful, thankyou! Another question. If I remove the Flash Card and attempt to boot the router without it, with the boot config command in place, will it boot to its original startup-config or hang at the >rommon prompt?
Sorry, haven't used it in a while so not 100% sure but from memory it does not default to NVRAM so if you specify a location such as flash and it can't find it then it won't boot which sounds like what you want. Worth testing though.