On Wednesday 09 December 2009 23:57:18 Stroller wrote: > On 9 Dec 2009, at 19:42, Alan McKinnon wrote: > > ... > > Installation is supposed to be an atomic operation - it > > starts then continues till it ends. It either fully completes or is > > considered > > to not have happened, meaning that persistence is diametrically > > opposed to > > what an install is. It's analogous to a compile - terminating > > compilation at > > some arbitrary point then picking up from where it ended at some > > later point > > is just not supported. Possible yes, but not supported by default. > > I'd disagree with you on that point, assuming I'm reading you right. > > If a compile fails it shouldn't be an "unsupported" situation. One > should be able to reemerge the package, possibly after emerging a > required dependency first. That should work just fine (and surely it > always does?).
I made an analogy, a poor one :-), which only goes as far as it goes (and that's not very far). I meant that if gcc is running and compiling some arbitrary .c and you hit ^C, there's no magic incantation to tell gcc to find what it was doing and continue from that point as if the interruption never happened. Likewise with installation - you can't just decide to stop halfway, shut the box down and continue tomorrow expecting the software to pick up where you left off automagically (without you having to do anything extra). Consider *any* installation media of your choice for *any* OS; none of them that I have ever used allow you to interrupt the install and continue later. I see no reason why the install dev and the doc dev should support such a feat on Gentoo even if it is technically feasible. > Likewise it's not at all uncommon to make a mistake during the > installation process - to miss out an essential kernel driver or > package, and find that the installation fails to boot. The way I > interpret your statement is that the supported remedy is to start > again completely from scratch. Clearly this is not what one does Correct, one normally redoes the setup commands: boot, mkdir, mount, mkmoredirs, more mount, mount proc, chroot, cp resolv.conf etc etc etc and continue. This only works because any data written to the disk during $INSTALL_ATTEMPT_1 is persistent by virtue of it being written to *disk*. And there is no need to untar a stage all over again. By happy coincidence, oftentimes after chrooting one finds an environment that has everything required to run sshd, but there is no guarantee of that at all. So one can try start sshd, if it works then all well and good, if not then that's tough. Either way the human running the show is on his own with this one. I still maintain that the doc dev is correct in refusing to document such a thing - it's way too unreliable and uncertain to even warrant a mention. -- alan dot mckinnon at gmail dot com
