reboot
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From: neilsolent on 17 Jan 2010 10:35 Automatic? Careful - that's sounding a lot like a script 8-O
From: Rainer Weikusat on 17 Jan 2010 11:19 neilsolent <n(a)solenttechnology.co.uk> writes: > On 16 Jan, 22:26, David Schwartz <dav...(a)webmaster.com> wrote: >> On Jan 16, 7:52�am, neilsolent <n...(a)solenttechnology.co.uk> wrote: [...] >> > On Solaris, I find /usr/bin/shutdown does not seem to SIGTERM all the >> > processes (I guess - it assumes every process has a shutdown script if >> > it needs it). I find the reboot command does send a SIGTERM to the >> > processes. Ideally - the shutdown scripts are run, and remaining >> > processes are signalled. >> > Thoughts / experiences anyone? >> > What's a standard script for rebooting UNIX? >> >> There is no standard script. Every system is different, and rightfully >> and necessarily so. >> >> Why are you rebooting the machine from a script anyway? > > Why write a script to do anything? > We could all just do a lot of typing - it's fun :-) It's a waste of time in this case: If reboots aren't infrequent enough that doing them manually doesn't matter, that hints at another problem which should be solved first. Especially, since 'rebooting' necessarily means 'interruption of service'. This doesn't matter much if some user choses to reboot is 'GUI typewriter' because it doesn't affect anyone except himself. But this is not true for anything running servers, programs which are intended to provide services to other programs, eg, for the sake of the example, let's assume that a computer providing DHCP is being rebooted: Until this service is again available, people trying to use 'the network' from their computers will run into all kinds of problems. It doesn't really matter if there are only five minutes of downtime should someone important enough chose to reboot his laptop for some reason during this period.
From: David Schwartz on 17 Jan 2010 14:33 On Jan 16, 11:21 pm, neilsolent <n...(a)solenttechnology.co.uk> wrote: > > Why are you rebooting the machine from a script anyway? > Why write a script to do anything? > We could all just do a lot of typing - it's fun :-) I'm trying to understand your problem so I can help you solve it. If you're in some special circumstance where it makes sense to reboot a machine from a script, that might suggest how the reboot has to be accomplished. You may wish to go to this website http://www.thewebsiteisdown.com/ and watch episode 1. Particularly the "did you just reboot the web server?" part wherein a support guy is bullied into rebooting a perfectly-working server (because someone "said that was what you guys did last time it wasn't working") only to discover the server won't reboot properly and needs to be unplugged and plugged back in. A bit of confusion over the phone line causes the "remote hands" guy to unplug a different computer as well... You have to see it. Typically, rebooting a machine requires coordination among multiple humans and multiple services. If you reboot some machines without first disarming their remote monitoring, ... DS
From: neilsolent on 18 Jan 2010 06:47 On 17 Jan, 16:19, Rainer Weikusat <rweiku...(a)mssgmbh.com> wrote: > neilsolent <n...(a)solenttechnology.co.uk> writes: > > On 16 Jan, 22:26, David Schwartz <dav...(a)webmaster.com> wrote: > >> On Jan 16, 7:52 am, neilsolent <n...(a)solenttechnology.co.uk> wrote: > > [...] > > >> > On Solaris, I find /usr/bin/shutdown does not seem to SIGTERM all the > >> > processes (I guess - it assumes every process has a shutdown script if > >> > it needs it). I find the reboot command does send a SIGTERM to the > >> > processes. Ideally - the shutdown scripts are run, and remaining > >> > processes are signalled. > >> > Thoughts / experiences anyone? > >> > What's a standard script for rebooting UNIX? > > >> There is no standard script. Every system is different, and rightfully > >> and necessarily so. > > >> Why are you rebooting the machine from a script anyway? > > > Why write a script to do anything? > > We could all just do a lot of typing - it's fun :-) > > It's a waste of time in this case: If reboots aren't infrequent enough > that doing them manually doesn't matter, that hints at another problem > which should be solved first. Depends how many systems are being rebooted. Also, scripts do more than save typing - help to prevent typos as well, and save you from having to remember a procedure. > Especially, since 'rebooting' > necessarily means 'interruption of service'. No it doesn't. System may be clustered, for example. > This doesn't matter much > if some user choses to reboot is 'GUI typewriter' because it doesn't > affect anyone except himself. But this is not true for anything > running servers, programs which are intended to provide services to > other programs, eg, for the sake of the example, let's assume that a > computer providing DHCP is being rebooted: Until this service is again > available, people trying to use 'the network' from their computers > will run into all kinds of problems. It doesn't really matter if there > are only five minutes of downtime should someone important enough > chose to reboot his laptop for some reason during this period.
From: neilsolent on 18 Jan 2010 06:54
On 17 Jan, 19:33, David Schwartz <dav...(a)webmaster.com> wrote: > On Jan 16, 11:21 pm, neilsolent <n...(a)solenttechnology.co.uk> wrote: > > > > Why are you rebooting the machine from a script anyway? > > Why write a script to do anything? > > We could all just do a lot of typing - it's fun :-) > > I'm trying to understand your problem so I can help you solve it. If > you're in some special circumstance where it makes sense to reboot a > machine from a script, that might suggest how the reboot has to be > accomplished. ... and I have given up on getting any useful info from this thread! I am just enjoying the banter instead :-) > You may wish to go to this websitehttp://www.thewebsiteisdown.com/ > and watch episode 1. Particularly the "did you just reboot the web > server?" part wherein a support guy is bullied into rebooting a > perfectly-working server (because someone "said that was what you guys > did last time it wasn't working") only to discover the server won't > reboot properly and needs to be unplugged and plugged back in. A bit > of confusion over the phone line causes the "remote hands" guy to > unplug a different computer as well... You have to see it. > > Typically, rebooting a machine requires coordination among multiple > humans and multiple services. If you reboot some machines without > first disarming their remote monitoring, ... > > DS Yes, and broadly I agree. This is your assumption though - that I am attempting to reboot systems willy nilly. All I was asking was about how to reboot a UNIX system from a C program. There are plenty of commerical 3rd party apps out there that do this. Let's say it's up to the user whether he wants to do it or not, I just provide the capability. In my opinion, there should be standards such that you can just call a simple command to do a reboot - and all the complexity of taking care of the applications etc is hidden from the user (typically implemented by shutdown scripts, or whatever). This is not because the user is stupid, but because it's not practical to remember the exact source code for every application running when he is aksed to do a reboot at 3am in the morning. |