ORA-03113: end-of-file on communication channel

I haven't the slightest what this error means, and I can't find it in my documentation...here's the context:

        $ svrmgrl

        Oracle Server Manager Release 2.3.2.0.0 - Production

        Copyright (c) Oracle Corp. 1994, 1995. All rights reserved.         

	ORA-03113: end-of-file on communication channel
	SVRMGR> connect internal
	Password:
	ORA-12571: TNS:packet writer failure
	SVRMGR>

Oh, yes...I haven't the slightest what that means either.

This is my first time administering Oracle, and I did not set up this box (which appears to have Oracle installed twice). Any pointers in the right direction will be greatly appreciated...especially if I'm missing something simple and obvious. (No one else in the building uses Oracle, either, so I'm on my own with this one...which, if I didn't *have* to get it going right away, would be kinda fun! But...)

	John Adams
	John.Adams_at_BentonvilleAR.ncr.com