Killing a process when desktop hang

[paul cooke]

On Tuesday 27 June 2006 16:04, Haines Brown wrote:
> > > Thanks for the suggestion, but the problem is that my entire desktop
> > > is hung, not just the application. C-M-F3 does not take me to a
> > > console, and C-M-BkSp does not shut down the X server.
> >
> > I've had the same problem, the only solution I've found working is to
> > login with SSH from another machine and kill the app that have hung the
> > GUI. No keystrokes at all work. Quite serious bug imho, but I don't know
> > what causes it :/
> >
> > //Marcus
>
> Marcus,
>
> If I may be allowed to ask a OT naive question:
>
> The remote host with the hung desktop is connected to port 1 of my
> hardware firewall, while my local client is on port 0. The ubuntu
> remote host, not having been entirely set up, is not configured
> for networking, and so has no IP address to put into my local client's
> /etc/hosts. My firewall allows ssh outgoing, but not incoming.
>

barring a hard shutdown using the power switch or hitting the reset button on 
the case, this is your only hope...

http://linuxgazette.net/issue81/vikas.html

never had to use it myself... don't know if it works or not or even if Ubuntu 
has had support for it compiled into the kernel.

Good news for you... it's enabled.

|paulc at broken-drum:~$ cat /proc/sys/kernel/sysrq
|1


ps. this is bad news for those running servers or having remote login

| Security
|
|Leaving magic SysRq enabled on a production machine can be potentially
|dangerous. Anyone with physical access to the machine can bring it down
|instantly.  
|You should also disable SysRq if other people can log in to your system
|remotely. A < break > sent from a remote console will be interpreted as <
|Alt+SysRq >, and the consequences can be disastrous. See the
|Remote-Serial-Console-HOWTO for more details.    

http://www.tldp.org/HOWTO/Remote-Serial-Console-HOWTO/index.html

> --
>
>        Haines Brown
>          KB1GRM
>          ET1(SS) U.S.S. Irex 482