> Yeah, that (sadly) is a good use case. But surely a proper package > management system would let you do this too. > > - allow more than one version of a package to be installed > > - allow more than one instance of the same package, but with different > global configuration. Perhaps global configuration is evil. > > - allow package dependencies to contol which versions of each package > talk to each other. For example, if A talks to B, under some > conditions, old A should talk to old B > > - make sure that distinct package's configurations don't affect each > other. Example: two different packages that use Apache; they should not > configure Apache in ways that conflict.
I think Red Hat's software collections are supposed to do that: https://www.softwarecollections.org On 22 April 2015 at 17:24, D. Hugh Redelmeier <[email protected]> wrote: > > | From: Giles Orr <[email protected]> > > | I've been using VirtualBox a lot recently, and I've been pretty > | impressed with it - running more than one simultaneous machine, > | setting up an internal network and running ansible between them, > | nifty. > > It is a neat trick. > > But what is it useful for? > > Clearly it is great to be able to run different OSes if you need to > run more than one. For example, to be able to run MS Word when you > mostly want to run Linux. Or to test on multiple platforms. > > In the Libreswan project, we use virtualization to test networking > software. Since some of the code is in the OS, we at least sometimes have > to run different OSes. > > But most of virtualization seems to be for other purposes. > > | Today at work we had an interesting discussion about Digital > | Ocean: the suggestion was made (and undoubtedly it's obvious to many > | on this list, but it was eye-opening to me, I'm still getting my head > | around disposable machines) that if you weren't sure an upgrade to a > | droplet would work, just clone it, do the upgrade on the clone and see > | how it goes. Then you can make your decision and destroy the unwanted > | version. > > Yeah, that (sadly) is a good use case. But surely a proper package > management system would let you do this too. > > - allow more than one version of a package to be installed > > - allow more than one instance of the same package, but with different > global configuration. Perhaps global configuration is evil. > > - allow package dependencies to contol which versions of each package > talk to each other. For example, if A talks to B, under some > conditions, old A should talk to old B > > - make sure that distinct package's configurations don't affect each > other. Example: two different packages that use Apache; they should not > configure Apache in ways that conflict. > > - job migration between machines, even while running, seems useful. > (That's not a package management problem.) > > One step more towards virtualization: > > Jails are minimal and may be good enough but a lot cheaper than > supporting true virtual x86 machines. > > | All of which made me think "wouldn't it be cool if I could > | have a system with an totally stripped Linux with VirtualBox as the > | "Window Manager" so I could toggle between two or three running OSes > | with graphical interfaces ..." So: > > I think that Serious VMware products are stripped Linux systems that > can run VMs without a lot of extras. > > I think that Zen Dom0 (host) can be minimal too. > > So much of the noise this day is about things like Docker and CoreOS. > A lot feels like branding exercises rather than technology. I find it > too hard to figure out what they actually are. > --- > Talk Mailing List > [email protected] > http://gtalug.org/mailman/listinfo/talk --- Talk Mailing List [email protected] http://gtalug.org/mailman/listinfo/talk
