On 10/07/18 20:38, Martin Gregorie wrote:
> On Tue, 10 Jul 2018 18:29:40 +0000, bob prohaska wrote:
>
>> Is there a command that will save the present state of the system,
>> reboot and then pick up where it left off?
>>
> Yes
>
> "shutdown -r NOW" or "reboot" - run as root or via sudo.
>
>
> But note that rebooting will stop all processes and close all network
> sessions. There's no way round that.
>
>> persist over at least a brief outage, so web and ssh-sessions should
>> survive if the downtime doesn't last too long.
>>
> Nossir. Its not the duration of the gap but killing restarting the Linux
> kernel that stops programs and closes network connections. Some daemons,
> such as postfix or postgres, have a 'reload' command that do the sort of
> very fast shutdown and restart. These can be run without a kernel reboot,
> but are specific to the service they provide.
>
> This is why I never leave system updates to run on autopilot: I turn
> automatic updating off. This way I control what's happening and do a
> weekly system update this involves these steps:
>
> 1) Stop whatever you're using the machine for - this includes shutting
>     down the web browser and mail reader, though I usually leave my
>     mail server running.
>
> 2) Do a system backup. I backup onto a pair of USB drives, using them in
>     strict rotation so one is always offline. I use rsync for this because
>     it is fast, only copying new material to the backup disk and
>     removing files from the backup that no longer exist on the system
>     being backed up.
>
> 3) Do the system update using apt_get and friends on the RPi and
>     dnf on Fedora systems.
>
> 4) reboot the system.
>
>> At one time I encountered
>> the notion of "checkpointing" long running jobs which could then be
>> restarted where they left off after system maintenance was done, but
>> that was 30+ years ago.
>>
> Programs that do this are still around, e.g. mailservers, DNS, the NTP
> server if you use it, and database servers. These generally use
> configuration options to determine how often they checkpoint themselves
> and/or provide a control system (like the 'reload' commands described
> above) to force a checkpoint, so reloads don't mess up the data.
>
> Others, e.g. databases like PostgreSQL or MariaDB, provide methods that
> their client programs can use to split the sequence of operations they
> request up into 'commitment units'. These are logical chunks of work that
> the server guarantees will be processed in their entirety or, in cases of
> software or hardware failure, by rolled-back as if they'd not been
> started.
>
>
In this machine, teh uodate deamon tells me when an update needs doing,
and I run it in background. I never exit out of anything.

Theowrst that has happened is that Firefox has crashed sometimes because
I didnt shut it down and restart it.

Nothing else has.

OTOH at one pont I got an unstable kernel upgrade that would not boot
after I restarted..I had to select a VERY old lernel and boot in
recovery mode. And uninstall several kernel versions


Rebooting has its downsides.

Admittedly this is a desktop INTEL machine not a pi...

--
There’s a mighty big difference between good, sound reasons and reasons
that sound good.

Burton Hillis (William Vaughn, American columnist)

--- SoupGate-Win32 v1.05