Tunnel has been disconnect

Hi

I have 2 router boards : RouterBOARD 3011UiAS and RB941-2nD.

I create a tunnel such as the ip tunnel or eoip

But when the power is lost or the router board is rebooted, my tunnel has been disconnected, and I’m forced to disable tunnel for 30 min and enable it again.

Anybody know what my problem is?