Re: Holding down the power button when the systems freezes
On Tue, Jan 29, 2013 at 2:56 PM, David G. Miller d...@davenjudy.org wrote: CTRL+ALT+F2 through CTRL+ALT+F6 (where F# = Function key #) will bring up an alternate console. Hold down Control and Alt then pick a function key. Get back to the GUI with CTRL+ALT+F1 on Fedora or CTRL+ALT+F7 on RHEL and clones. If the system is busy, you may have to wait a little while for it to respond. Another choice is CTRL+ALT+Backspace to kill the GUI. If you start in graphical mode, the GUI will restart. If you start in text mode, you'll get back to your original login session. Thanks, David, for your clear and detailed explanation. Paul -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
Allegedly, on or about 28 January 2013, Sam Varshavchik sent: 1) The hard drive does an emergency park of the R/W head. That does incur some cost, in terms of wear and tear. Are there any consumer hard drives that still do a controlled park, rather than just get switched off? -- [tim@localhost ~]$ uname -rsvp Linux 3.6.11-5.fc17.x86_64 #1 SMP Tue Jan 8 21:40:51 UTC 2013 x86_64 All mail to my mailbox is automatically deleted, there is no point trying to privately email me, I will only read messages posted to the public lists. -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
2013/1/29 Sam Varshavchik mr...@courier-mta.com: When the machine freezes, try pressing Alt-SysRq-b to force a reboot, if the kernel is still alive, somewhere. This will still require a filesystem repair, but at least it'll save wear/tear on the hard drives. Even better is to use Alt + SysRq + REISUB (sequentially) R = unRaw (take control of keyboard back from X), E = tErminate (send SIGTERM to all processes, allowing them to terminate gracefully), I = kIll (send SIGKILL to all processes, forcing them to terminate immediately), S = Sync (flush data to disk), U = Unmount (remount all filesystems read-only), B= reBoot. http://en.wikipedia.org/wiki/Magic_SysRq_key Greetings, -- Jorge Martínez López jorg...@gmail.com http://www.jorgeml.net -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
On Tue, Jan 29, 2013 at 4:24 AM, David G. Miller d...@davenjudy.org wrote: When the systems freezes, is it safe to hold down the power button to power off the machine? If not, what alternatives do you suggest? Simple test: if CapsLock and/or NumLock and/or ScrollLock still work (keyboard light reflects change in state), you have a shot at the Alt-SysReq-key stuff. The keyboard lights are actually controlled by the O/S (keyboard driver specifically). If the O/S is dead, the lights won't change state when you push whatever. I've had fairly good luck with this test. Lights work -- be patient and see if you can get an alternate console, shell in, etc. Lights don't work -- power key time. Thanks, David and all other respondents. In case lights works, how can one get a console? Paul -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
Tim writes: Allegedly, on or about 28 January 2013, Sam Varshavchik sent: 1) The hard drive does an emergency park of the R/W head. That does incur some cost, in terms of wear and tear. Are there any consumer hard drives that still do a controlled park, rather than just get switched off? On my laptop with a ~4 year old hard drive, there's quite an audible difference between a forcible power-off, with a clunk, and an orderly shutdown that turns the power off quietly. pgpOJ3dMDttRK.pgp Description: PGP signature -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
On Tue, 29 Jan 2013, Paul Smith wrote: On Tue, Jan 29, 2013 at 4:24 AM, David G. Miller d...@davenjudy.org wrote: When the systems freezes, is it safe to hold down the power button to power off the machine? If not, what alternatives do you suggest? Simple test: if CapsLock and/or NumLock and/or ScrollLock still work (keyboard light reflects change in state), you have a shot at the Alt-SysReq-key stuff. The keyboard lights are actually controlled by the O/S (keyboard driver specifically). If the O/S is dead, the lights won't change state when you push whatever. I've had fairly good luck with this test. Lights work -- be patient and see if you can get an alternate console, shell in, etc. Lights don't work -- power key time. Thanks, David and all other respondents. In case lights works, how can one get a console? Ok, I'll play. humor It all depends on how much room you have in the living room; sometimes all you can fit there is a spinet. But if the space is there, go for a grand. /humor If you're running a LAN/home network and you have other machines on the network, and provided those machines have some ssh/telnet client software, and the (blanket-wrapped) frozen machine is running a telnet/ssh daemon and set to receive requests, you try accessing the (supposedly) frozen machine by ssh/telnet client. If can login successfully, then you can try doing some forensics (looking for log files, and other evidence/detris), and in the end, if necessary, reboot the box (usually, su to root, type reboot, and politely tap enter). Paul fyi, Max PYziur p...@brama.com -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
Tim: Are there any consumer hard drives that still do a controlled park, rather than just get switched off? Sam Varshavchik: On my laptop with a ~4 year old hard drive, there's quite an audible difference between a forcible power-off, with a clunk, and an orderly shutdown that turns the power off quietly. Hmm, I'll have to have a listen out for what my laptop does. I can well imagine laptops having an emergency shutoff, seeing as some of them use motion detectors to protect drives against bangs. But my external drives seem to make the same loudish bang when they put themselves to sleep, compared to losing power. To be honest, I think external drives need motion detection. All too often people move them about while they're running. And the ones that sit upright aren't the most stable of things. -- [tim@localhost ~]$ uname -rsvp Linux 3.6.11-5.fc17.x86_64 #1 SMP Tue Jan 8 21:40:51 UTC 2013 x86_64 All mail to my mailbox is automatically deleted, there is no point trying to privately email me, I will only read messages posted to the public lists. -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
On 01/29/2013 03:28 AM, Tim wrote: Allegedly, on or about 28 January 2013, Sam Varshavchik sent: 1) The hard drive does an emergency park of the R/W head. That does incur some cost, in terms of wear and tear. Are there any consumer hard drives that still do a controlled park, rather than just get switched off? If you look at a drive's SMART attributes, you will probably see separate Power Cycle Count and a lower Power-Off Retract Count. Or, perhaps not -- depending on the drive and, of course, how it's been shut down. I have one drive that, even when it is already spun down in standby, will make an audible click and peg the Power-Off Retract Count when power is turned off. The rest of mine do not. -- Bob Nichols NOSPAM is really part of my email address. Do NOT delete it. -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
Max Pyziur pyz at brama.com writes: On Tue, 29 Jan 2013, Paul Smith wrote: On Tue, Jan 29, 2013 at 4:24 AM, David G. Miller dave at davenjudy.org wrote: When the systems freezes, is it safe to hold down the power button to power off the machine? If not, what alternatives do you suggest? Simple test: if CapsLock and/or NumLock and/or ScrollLock still work (keyboard light reflects change in state), you have a shot at the Alt-SysReq-≤key stuff. SNIP Thanks, David and all other respondents. In case lights works, how can one get a console? Ok, I'll play. SNIP If you're running a LAN/home network and you have other machines on the network, and provided those machines have some ssh/telnet client software, and the (blanket-wrapped) frozen machine is running a telnet/ssh daemon and set to receive requests, you try accessing the (supposedly) frozen machine by ssh/telnet client. SNIP CTRL+ALT+F2 through CTRL+ALT+F6 (where F# = Function key #) will bring up an alternate console. Hold down Control and Alt then pick a function key. Get back to the GUI with CTRL+ALT+F1 on Fedora or CTRL+ALT+F7 on RHEL and clones. If the system is busy, you may have to wait a little while for it to respond. Another choice is CTRL+ALT+Backspace to kill the GUI. If you start in graphical mode, the GUI will restart. If you start in text mode, you'll get back to your original login session. Cheers, Dave -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
Tim writes: Hmm, I'll have to have a listen out for what my laptop does. I can well imagine laptops having an emergency shutoff, seeing as some of them use motion detectors to protect drives against bangs. But my external drives seem to make the same loudish bang when they put themselves to sleep, compared to losing power. That seems to be rather broken. I can't claim to be a big HD expert, but having the platters stop spinning with the heads still flying over the platters will crash the heads, and permanently ruin the drive, so the heads must return to their parking position before the drive stops spinning. In an orderly shutdown, the heads get returned to their parking spot, during ordinary course of business, then the power goes off. The clunk is when the drive detects a loss of power, and it's using its reserve power, in some capacitor or something, to just yank the heads out of the way, ASAP, to avoid a head crash. It's got limited power, so it can't waste milliseconds bleeding it off by moving the heads slooowly to their parking spot. So, they get yanked off the platter, ASAP. And the clunk is the heads slamming against the end stop. Which is preferrable to having the heads crash on the platters. If your drive knows it wants to go to sleep, it should be moving the heads normally into the parking location, instead of just cutting off its own power, and have the heads go into an emergency retract. pgpjnIJIRechE.pgp Description: PGP signature -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
On 01/28/2013 04:57 PM, Paul Smith wrote: Dear All, When the systems freezes, is it safe to hold down the power button to power off the machine? If not, what alternatives do you suggest? My laptop doesn't do that. My desktop does, and most of the time I have to use the reset button, but if that doesn't work, there's nothing left except the power button and if so, there's not really much else I can do. You might try activating the Magic SysRq key (http://www.linuxhowtos.org/Tips%20and%20Tricks/sysrq.htm) and seeing if that works, but for me, it only works when it's not frozen. -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
Paul Smith writes: Dear All, When the systems freezes, is it safe to hold down the power button to power off the machine? If not, what alternatives do you suggest? Thanks in advance, There are two consequences to a hard poweroff, like that: 1) The hard drive does an emergency park of the R/W head. That does incur some cost, in terms of wear and tear. 2) The filesystem state is inconsistent. That does not usually result in any damage. The filesystem should get automatically re-fscked on the next reboot. Still, after a forced poweroff, it is a good idea to touch /forcefsck and reboot one more time, to force a full fsck on all filesystems (which will take some time to complete). As far as recovering, there are basically two things that can be tried, before giving up and yanking the power. A) Sometimes only X, or the UI is frozen, but the kernel continues to crawl, to some extent, underneath. If you were connected to a network, you can try ssh-ing in, and running 'poweroff'. Of course, this assumes that you had ssh enabled. If you're able to ssh-in and execute 'poweroff', be patient, it may take 5-10 minutes for a crippled machine to figure out how to kill off everything, and reboot. B) Execute: echo 'kernel.sysrq = 1' /lib/sysctl.d/99-sysrq.conf sysctl --system When the machine freezes, try pressing Alt-SysRq-b to force a reboot, if the kernel is still alive, somewhere. This will still require a filesystem repair, but at least it'll save wear/tear on the hard drives. pgpKNpb3G9NzK.pgp Description: PGP signature -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
On 01/29/2013 12:57 AM, Paul Smith wrote: Dear All, When the systems freezes, is it safe to hold down the power button to power off the machine? If not, what alternatives do you suggest? looking for more fish? (GBWG) if your system is freezing, put a heavy blanket around it to keep it warm. if the power button is on top of machine, holding it _down_ is ok. if power button is on the front, holding it _in_ would work better. your alternatives would be pulling power cord from back of machine or removing power cord plug from wall. main thing is, does machine freeze often and what is causing it to freeze up. Thanks in advance, again, you are welcome. -- peace out. tc.hago, g . *please reply plain text only. html text are deleted* signature.asc Description: OpenPGP digital signature -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
On 01/28/2013 05:31 PM, Sam Varshavchik wrote: When the machine freezes, try pressing Alt-SysRq-b to force a reboot, if the kernel is still alive, somewhere. This will still require a filesystem repair, but at least it'll save wear/tear on the hard drives. In an ext3/ext4 filesystem, journaling will often correct any errors without needing to fsck; if not, the system will do it on its own at boot. And, if the Magic SysRq is working, using Alt-SysRq-s will force a sync before forcing a boot. I need to do ^Alt-SysRq to get it to work and then, only if the system hasn't locked up. -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
On 1/28/2013 5:36 PM, g wrote: if your system is freezing, put a heavy blanket around it to keep it warm. Life would be so much easier if it was this easy ... Thanks, Paul -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
On 01/29/2013 01:50 AM, Paul Allen Newell wrote: On 1/28/2013 5:36 PM, g wrote: if your system is freezing, put a heavy blanket around it to keep it warm. Life would be so much easier if it was this easy ... more true than many realize. -- peace out. tc.hago, g . signature.asc Description: OpenPGP digital signature -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
Re: Holding down the power button when the systems freezes
Paul Smith phhs80 at gmail.com writes: When the systems freezes, is it safe to hold down the power button to power off the machine? If not, what alternatives do you suggest? Simple test: if CapsLock and/or NumLock and/or ScrollLock still work (keyboard light reflects change in state), you have a shot at the Alt-SysReq-key stuff. The keyboard lights are actually controlled by the O/S (keyboard driver specifically). If the O/S is dead, the lights won't change state when you push whatever. I've had fairly good luck with this test. Lights work -- be patient and see if you can get an alternate console, shell in, etc. Lights don't work -- power key time. Cheers, Dave -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
