I have a problem with Cisco ISR G2 2911 series routers. One of our clients has 50 routers in WAN network. All routers are totally new and in function only three months. BUT, three of them are DEAD. When I say DEAD I mean: they have no cooler activity, they can not boot and there is absolutely no activity of any kind. All routers are not directly connected to the power grid, they all have UPS. Do you have any explanation for this kind of behavior?
P.S: Sorry for my english