RJ45 Device that can serve as a IP host and respond to pings being sent to it

Hi,

I have know idea if anything exists like this, but the use case I have is for end-to-end testing in my lab in the hopes of not having to have a separate host connected to a network interface that I want to be able to ping. I understand that it would need to have the ability to have the IP information configured on it before hand. Has anyone heard of such a device or something that could fill the same purpose?