How to enter DDB through a terminal server / remote console ... ?

[Robert Watson]

On Wed, 28 Jun 2006, User Freebsd wrote:

> 'k, now that I'm up to 3 6-STABLE servers that are deadlocking, I'm spending 
> time with the remote tech today to get a serial console put online ... how 
> do I drop into DDB remotely, where the serial console is going through a 
> Portmaster Terminal server?  issuing CTL-ALT-ESC, I doubt, will work, will 
> it?

If configured to use a serial console (console="comconsole" in loader.conf), 
you can enter the debugger with BREAK_TO_DEBUGGER in the kernel config by 
sending a serial break.  With my portmasters, I telnet to a TCP port to 
connect to the serial console, so I send a telnet break, using ^]send break.

Robert N M Watson
Computer Laboratory
University of Cambridge