Sarah Jelinek wrote: > Dave Miner wrote: >> Sarah Jelinek wrote: >>> Dave Miner wrote: >>>> Evan Layton wrote: >>>>> Dave Miner wrote: >>>>>> Evan Layton wrote: >>>>>>> Problem statement: >>>>>>> >>>>>>> 1) A method is needed to match the OS version the AI server is >>>>>>> running on with >>>>>>> the OS version being installed. >>>>>> >>>>>> As Ethan noted, you mean "client" here. >>>>> >>>>> Yes that's correct. It probably should have be something more like >>>>> "the OS version being installed on the client". >>>>> >>>>>> >>>>>>> Note: There is currently information being logged which shows >>>>>>> this but it's not used for anything. >>>>>>> 2) A method of determining which OS version can support >>>>>>> installions of >>>>>>> which OS versions is needed. >>>>>>> 3) This is something that the user should not have to keep track of >>>>>>> and should be maintained internally. Should incompatibilities be >>>>>>> documented so that users can at least look up why we're >>>>>>> telling them >>>>>>> that they have incompatible OS versions? >>>>>>> >>>>>> >>>>>> I think the part that's missing here is providing means to limit >>>>>> the incompatibility set. For example, installing an updated >>>>>> version of pkg into the installation environment once booted, or >>>>>> other software that we might need. >>>>> >>>>> OK so this is an additional requirement that all the needed >>>>> packages and their proper versions are installed on the client. In >>>>> other words all the correct packages corresponding to the version >>>>> of the "entire" package are installed on the client? >>>>> >>>> >>>> I don't think that's quite what I'm suggesting. I'm suggesting that >>>> the client be capable of dynamically adapting itself to run the >>>> versions of executables required to correctly install a particular >>>> version of the software. >>> >>> This seems like a good overall goal to have, but my concerns about >>> this are that the executables required might not be limited enough in >>> scope to be able to effectively do this. I would think we would need >>> to have an understanding of how many versions we would be willing to >>> be 'off' or what/how many executables would need to change to make >>> this work. >>> >>> Just allowing an 'open' dynamic updating of the client seems too >>> unpredictable. >>> >> >> I agree there are challenges, but IPS solves at least some of the >> problems for us. One kind of "out there" idea I've had rattling >> around in my mind is packaging the automated installer environment as >> a zone and using the update-on-attach capability. >> > That might work. An interesting idea. If we separate out the 'installer' > from the boot image, we could more easily manage the versioning issues. > So,even if it isn't a zone, the separating of these two things would > make it easier for us to manage the current issues we are having. > > I do think that we need to understand the specific scope of what we will > 'manage' in terms of version incompatibilities: > > 1. We won't allow a newer boot image to install an older version of the > bits. This scenario is unpredictable, in my opinion, and one we should > avoid. Putting the older version of the installer on the new boot image > seems problematic and one in which we don't fully understand the > potential issues. I could imagine a lot of surprises. > > 2. We will allow an older boot image to install newer bits. We have to > manage getting the 'installer' on the client up to the version it needs > to be to handle the bits being installed. > >
This may not always be possible if the libraries we depend on such as libzfs are not compatible with the installer and libbe required to correctly handle the bits being installed. We would still need at way to version this and state that this older boot image is not able to install the requested image. -evan >
