Massimiliano Tarquini wrote:

It seems to be exactly what is happening. I have noticed a new think. When the radius crash, the database administration interface continue showing the connection to the radius. Using netstat onto the radius server there are no connection to the database SERVER. Is it possible?

Yes. It's exactly what I have been trying to say.

May be the firewall?

As I said, yes, it's the firewall. Stop trying to debug the problem. Stop trying to understand it. Go fix the firewall so that it doesn't destroy your network. Alan DeKok.