On Tuesday, January 8, 2002, at 04:09 PM, Andrew Gallatin wrote: Andrew Gallatin writes: Umesh Vaishamapayan writes: Well, if you build and run DEBUG kernel, you get ddb... A clarification: You get Mach kdb [which is similar to FreeBSD ddb] Excellent! That's exactly what I want. Thanks for the tip. Now, to figure out how to get my dual g4 800 to actually boot a different kernel than the default one.. :) I've finally managed to get another g4 (I'm at a different office) to boot a debug kernel. Now, when this machine panics, I see: <stack trace> Waiting for remote debugger connection. Options..... Type ------------ ---- continue.... 'c' reboot...... 'r' enter kdb... 'k' However, I cannot seem to type anything on the "graphics" console. I was logged into the console at the time of the crash in text mode, via entering >console as the username; eg no windowing was running. Do I need to be running with a serial console? Or doing anything else differently? Or is it looking to talk kdb over the network? The 'waiting for debugger' message indicates that, by default, the system is awaiting a connection via the network. For this, you need a second system, running a Darwin version of gdb that knows how t speak 'kdp' (a simple-minded, UDP-based, request/response protocol). If you type 'k', you will (should) end up talking to the Mach debugger, KDB, which understands the Mach infrastructure, but not the BSD part. You will (should) interact with it via the console/keyboard (there are ways to have the system use a serial console, but it's tricky, and I don't know if it's been checked out recently; and then there's the matter of the serial interface). If 'c', or 'r', doesn't work, you have some other problem. Not sure what to do in that case. Have you tried the 2-machine setup? Regards, Justin -- Justin C. Walker, Curmudgeon-At-Large * Institute for General Semantics | It's not whether you win or lose... | It's whether *I* win or lose. *--------------------------------------*-------------------------------*