Device needed to manage several FreeBSD servers

[patrick]

I have a bunch of FreeBSD servers to manage, and I'm wanting to find a
device that lets you SSH/telnet in, and access the servers connected
to it via serial cables. I know such a device exists, but it was a
long time ago since I last saw one, and I'm not really sure what one
of these would be called. Has anyone had any experience with such a
device?

Thanks,

Patrick