Reliability of reboot after firmware upgrade

I was out travelling last week and my IMP stopped pinging my web server which I put it down to a result of a firmware upgrade. A simple power cycle upon my return solved this and the IMP carried on with it’s daily activity.

However, This does raise a concern that the reboot did not automatically happen. How reliable is this ? I’m monitoring my home alarm system and wouldn’t like it to simply stop working because there is a firmware update.


It’s unlikely to have been the firmware update, but there is still a scenario where the imp can become disconnected without noticing; pings to keep the link up are server initiated, so if the router decides to close the NAT port the imp never sees them. In this case, the server will know the imp is offline but the imp won’t, hence it won’t ever reconnect.

The current workaround for this is to add a heartbeat transmission from the imp, which will cause a reconnect if the connection goes down. Try adding this code to your imp:

function heartbeat() {


… we will be adding a client initiated ping in a future release so this won’t be necessary then.