Hi Aneurin, I'd expect one of the design goals of the whole image-update process was to work with as little interruption as possible (we had this in live upgrade as well, so the historical precedent is fairly clear, IMO anyway): you could run your update, watch it finish, analyse logs etc., all while the machine (think "big server") was up and running *completely unchanged*. Only when/if you're satisfied that the update did what you expected it to do, you could (schedule a) reboot. IMO that's a much safer approach than what you describe.
cheers Michael On Mon, Jun 25, 2012 at 4:18 PM, Aneurin Price <[email protected]>wrote: > Hi folks, > > I have a basic newbie question: can somebody help me to understand how > exactly the boot environments created by 'pkg image-update' work? > > Lets say I start with the BE 'mysystem'. My initial expectation - > obviously incorrect - was that performing the update would take a > snapshot (call it 'mysystem-1'), and create a corresponding BE, then > apply the relevant updates to the *currently active* BE. Then I would > immediately have access to updates that don't require a restart (new > application software versions etc.); I can reboot to get the new > kernel version, or I can reboot and choose the mysystem-1 BE if > anything went wrong. > > In short, I was expecting the operation to be roughly equivalent to > snapshot creation, followed by 'apt-get dist-upgrade'. > > That obviously isn't the case, but I can't find a clear explanation > anywhere of how the process actually works. From observation it > appears to be the following: a snapshot and corresponding BE are > created, and the update process is applied to that *new* BE. Thus > newly installed updates aren't available until rebooting into that new > BE. The current BE effectively acts as the 'backup' snapshot, so any > other changes to the system (applied to the running environment) not > only won't apply to the new BE, but are basically modifying the > backup. Hence, updating should be the *very last* thing to do before a > reboot, and rebooting ASAP after performing the update is *extremely* > important. > > Is that understanding correct? > > Assuming so, is it possible to make pkg behave more like my initial > expectation? I suppose I could create a snapshot myself using beadm, > then tell pkg not to create a new environment, but is that likely to > bite me in some nasty way? I'd like a better understanding of why the > system works the way it does before trying to fight it :P. > > Thanks for your time. > > (PS: Apologies if this list is inappropriate for basic questions like > this; let me know if that's the case.) > > _______________________________________________ > OpenIndiana-discuss mailing list > [email protected] > http://openindiana.org/mailman/listinfo/openindiana-discuss > -- Michael Schuster http://recursiveramblings.wordpress.com/ _______________________________________________ OpenIndiana-discuss mailing list [email protected] http://openindiana.org/mailman/listinfo/openindiana-discuss
