[mythtv-users] Blue screen of death. [1st of 2 questions]

[Stephen Worthington]

On Sat, 21 Sep 2013 12:20:32 -0400, you wrote:

>On Sat, Sep 21, 2013 at 1:25 AM, Leif Pihl <leif at pihl.us> wrote:
>>> Did you try ctrl-alt-F1?
>>
>> Yea, that worked.  I was able to get into the command line mode, and Ctrl-Alt-F7 got me back into the graphics mode, such as it was, with the Blue Screen.
>
>Ok, if you're able to get to command line mode, there may be things
>you can do to recover the machine into working order without actually
>rebooting.
>
>The first thing I'd do is log in as root and see what the system is
>actually doing when it's in this state.  You can use the command "top"
>to show system activity.  Is the machine mostly idle or is some
>process active, and if so which ones?
>
>If it's the mythtv frontend process which has locked up you could try
>killing just that one process.
>
>I don't use Mythbuntu, so I'm not familiar with the details of how
>it's set up.  If it uses gdm or gdm3 to start the initial X session,
>you could also run, as root:
>
>/etc/init.d/gdm3 restart
>
>which should restart X.  (Can any Mythbuntu user on this list confirm
>that's the correct command?)

This command should find which display manager is currently running:

ps -e | grep dm

New Mythbuntu installs seem to use lightdm rather than gdm these days.
And it has been converted to an Upstart job.  When I was having VAAPI
freeze on exit from playing a program, this worked for restarting X:

restart lightdm

But /etc/inid.d/lightdm restart should still work too.

>>> Alt-PrintScreen-b?
>>
>> This worked, and did end up rebooting the machine.
>
>Just be careful with that one.  It's a fast reboot.  If you use it, I
>recommend using Alt-PrintScreen-s (sync filesystems), then
>Alt-PrintScreen-u (unmount filesystems) before doing the boot.
>
>Eric

For the purposes of debugging this, you might find it easier to log in
to the MythTV box using ssh from another PC (laptop?) if you have one
on the network, rather than having to use a Ctrl-Alt-Fx login as it is
likely to give you a much larger screen to work with for looking at
log files and so on.  Unless configured specially, Ctrl-Alt-Fx logins
are usually set up to use a very small (but almost universally
available) screen size like 800x600.  And the options to configure
their size at boot time are arcane and on my system are also
unreliable and depend on the connected monitor responding properly.  I
have these two lines in /etc/default/grub:

GRUB_GFXMODE=1280x1024x24
GRUB_GFXPAYLOAD=keep

but they only work on some boots.

If you do not have another Linux box with an ssh client installed, try
Putty on Windows:

http://www.chiark.greenend.org.uk/~sgtatham/putty/