Incomplete shutdown on some LTSP clients (shutdown hangs/freezes)

[John Hupp]

On the Lubuntu mail list, a poster on the equivalent thread (see 
https://lists.ubuntu.com/archives/lubuntu-users/2012-September/002356.html) 
reported that he solved the problem (presumably on a standalone desktop 
or on an LTSP server itself) by adding acpi=force to the boot parameters.

VERY intriguing.

Anyone know how to set an equivalent parameter for LTSP clients?

[Marco Muller posted to the LTSP mail list a solution that did not work 
for him.  See 
http://www.mail-archive.com/ltsp-discuss@lists.sourceforge.net/msg40651.html, 
but he reports that he edited
         /var/lib/tftpboot/ltsp/amd64/pxelinux.cfg/default
to add
         append ro initrd=initrd.img root=/dev/nbd0 init=/sbin/init-ltsp 
quiet splash acpi=force plymouth:force-splash vt.handoff=7 
nbdroot=:ltsp_amd64
and nobody posted a reply.]

And in connection with that configuration question (OK, I'm really 
showing my newbie stripes here), how do I verify whether ACPI is running?

On 9/2/2012 3:54 PM, John Hupp wrote:
> Some updates on this problem:
>
> The problem is not confined to LTSP clients.  I booted an Lubuntu Live 
> CD on one of the affected clients and found that it hung during 
> shutdown also.
>
> ----------------------------
>
> The problem is also not Gnome-specific, as someone suggested.
>
> I downloaded Kubuntu 12.04 (uses KDE rather than Gnome) and made a 
> Live DVD.
>
> On one of the clients with the shutdown problem, I booted the Live 
> DVD.  I didn't have a working pointer (500 MHz Celeron and 256 MB, so 
> maybe not enough resources), but the "sudo poweroff" command from a 
> console window resulted in shutdown hanging after "System halted" was 
> reported onscreen, and I had to force the machine off.
>
> ----------------------------
>
> I also played with the BIOS Power Control settings to no effect on one 
> of the affected machines.  For "ACPI Aware O/S: Yes/No" and "Power 
> Management/APM: Enabled/Disabled" I tried all four permutations of 
> BIOS settings and all resulted in the same hung shutdown.
>
> There were also other settings: "Power Button Function: On/Off," 
> "Suspend Time Out: Enabled/Disabled" and <various devices>: 
> "Monitor/Ignore," but I took those to be irrelevant.
>
>
> On 8/25/2012 2:30 PM, John Hupp wrote:
>> On my Lubuntu and Edubuntu 12.04 LTSP test networks, I find that some 
>> clients do not shut down completely.
>>
>> On the Lubuntu network, one eMachine client stops at a 
>> black-and-white text screen that says:
>>     Ubuntu 12.04
>>     .... * Asking all remaining processes to terminate ...
>>     [255.161402] SysRq : Power off
>>     [255.173722] Power down.
>>           [OK]
>>     [255.280060[ SysRq : Power Off
>>     [255.280220] Power down.
>>     * All processes ended within 1 seconds ....    [OK]
>> A simple press of the power button does not turn off the machine at 
>> that point.  I have to press and hold it 5 seconds or so.
>>
>> Also on the Lubuntu network, an HP stops at the same screen, but a 
>> simple press of the power button turns it off.
>>
>> A Dell on the Lubuntu networks shuts off cleanly and completely 
>> within a few seconds.
>>
>> ---------------------
>>
>> On the Edubuntu network, all clients have to invoke Shutdown from the 
>> desktop and from the login screen.  After choosing Shutdown from the 
>> desktop (and then presenting a dialog for Shutdown or Restart), it 
>> drops back to the login screen, and there one chooses Preferences: 
>> Shutdown.  [Very tedious, but that's not my real interest in this 
>> post.  And as a footnote, the server shuts down cleanly after the two 
>> clicks on the desktop.
>>
>> But regarding specific client machine behavior on the Edubuntu 
>> network, the above eMachine hangs at a black screen after 
>> Preferences: Shutdown from the login screen.  I forgot to make a note 
>> of whether a simple press of the power button shuts it off from here, 
>> or whether a press-and-hold was required as it was on the Lubuntu net.
>>
>> The above HP hangs at a white screen after Preferences: Shutdown from 
>> the login screen.  A simple press of the power button shuts it off 
>> from here.
>>
>> The above Dell shuts down cleanly after Preferences: Shutdown from 
>> the login screen.
>>
>> ---------------------
>>
>> One other behavior that was of interest to me but that I did not 
>> thoroughly document was that even on machines where Shutdown hangs, 
>> it seems generally to be the case that Restart does not hang.  The 
>> machine proceeds smoothly to POST and reboot.
>>
>> ---------------------
>>
>> So I am wondering if I can get all the clients to shut down cleanly 
>> via the interface Shutdown commands.
>>
>> If not, is there a script that will produce a clean shutdown?
>>
>> Or failing that, can I insert a splash screen at the end of the 
>> shutdown process something like Windows 95/98 used on machines where 
>> it could not execute a complete shutdown automatically?  (The screen 
>> said something like "It is now safe to turn off your computer.")
>>
>> Speaking of Windows 95/98's shutdown process, I recall that the issue 
>> had to do with power management drivers not fully supporting the 
>> hardware on some motherboards, or not finding the hardware that power 
>> management did fully support.  But beyond that, it was possible to 
>> not-install/uninstall/disable power management on machines that did 
>> support full shutdown, then install/reinstall/re-enable power 
>> management but not recover the ability to do a full shutdown.  So it 
>> wasn't always just a question of supported hardware.
>>
>> Also regarding Win 9x, that splash screen may have been an integrated 
>> part of all shutdowns.  I recall seeing it flash on-screen for a 
>> split second even on machines that were on their way to a full 
>> automatic shutdown.
>>
>>
>>
>
>
>

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