On Mon, Aug 22, 2022 at 01:58:57PM -0400, rhkra...@gmail.com wrote: > On Monday, August 22, 2022 08:50:02 AM Tom Browder wrote: > > Can anyone recommend a good book on the general topic of VMs? Or one on a > > specific VM stack (using Linux as base)? > > At this point, I've requested two books on the subject (by inter-library > loan) > -- one about 700 pages, the other about 280 (iirc) pages. > > It just seems documentation ought to be better / simpler / easier to use than > that. >
You could do worse than the original O'Reilly book on SSH. > Aside: I'm hoping to do my part -- when I get an understanding of the parts > of > ssh I want to understand to my level of satisfaction, I intend to document it > (on my WikiLearn wiki). I might even document it before then with notes > about > things I'm uncertain about or may have just plain omitted (for lack of > information). (I say that because I've spent too much time on this, and > we'll > soon have to concentrate on more urgent priorities.) > > Aside: I do recognize that when I started digging into ssh, and those methods > of authentication, I just didn't realize how complicated it is at some > levels, > with all the different encryption, hash, cipher or other related methods that > can be used, and things like Diffie-Hellman key exchange, but still,.. > > And there are other people trying to help by writing accurate yet simplified > stuff on things like wikis. > > Hmm, but I wonder, can I start to write something on VMs that might be > helpful > to the OP or to some other newbie to VMs? > > I might try, even though I have never used a VM (well, I might have once, > but, > at the moment, any recollection of that seems to be completely faded. > > So here's what I might try to tell someone. > > I'd say that a VM (virtual machine) can be used as at least one of its > purposes, to run some different software (maybe usually the OS, or including > an > OS) in a computer. > > For example, as was mentioned / recommended in some other recent thread, to a > person who wanted to run and old version of openssh (the version that ran on > Debian 9) on a computer with Debian 1 as an OS, is to create a VM and run > Debian 9 and its version of openssh in that VM. > > That can be done. There are issues to consider, like which and how the > hardware (and software) resources of the "parent" OS can be addressed by the > software in the VM. > > There are various programs / systems that can be used to set up a VM, and, > I'm > pretty sure there are options in at least some of those systems to address > the > questions of which and how the resources of the parent OS can be addressed by > the software in the VM. > > One example might be the question of can you cut and paste between the VM and > the parent (or, if there is more than one VM, can you cut and paste between > VMs). > > Others to consider (maybe): > > * can the software in the VM (directly) address filesystems in the parent, > or must either new filesystems be created in the VM or access explicitly > allowed for some filesystems > > * can the network be addressed from the VM > > * can you print from the VM > > Like I'm trying to imply, the answers to those questions may (probably does > vary) by the software used to create the VM and options that may or may not > be > set. > > I wonder if that is a helpful start, or what the next questions might be.... > > Oh, maybe a few more things: > > * terminology: I think VMs are sometimes referred to as containers. Also, > I think there are other things that are referred to as containers that are > not > VMs > A container need not be a full VM: in most cases a VM is more than a container. > * I have the idea that at least to some extent that the concept of VMs > somewhat evolved from the concept of chroot jails (so maybe a chroot jail can > be considered a sort of primitive version of a VM?) > > * I would list the names of a few software systems that can create a VM -- > not many of them come to my mind at the moment -- maybe qemu is one of them?? > > (I should google that, but I think I'm quitting for now.) > > Oh, ok, one "hit" from google [vm software for linux] -- oh, wait, what I > quoted is "opensource virtualization software" -- should I distinguish that > from VM (virtual machine) software, and, if so what is / are the > distinction(s)? (By the way, qemu is mentioned in some other hits.) > > <quote> > Which VM software is best for Linux? > Top opensource virtualization software for Linux > 1 > Oracle VirtualBox. VirtualBox. VirtualBox was founded in 2007 by Oracle > Corporation. ... Partially Free software, some parts have a personal use licence. Potentially avoid. > 2 > Linux KVM. KVM. ... Pretty much the standard. > 3 > Microsoft Hyper-V. Hyper-V-Manager. ... This is useful if the underlying machine is running Windows. WSL2 can also run on top of Windows and is a smaller shim than Hyper-V > 4 > Xen Project. Xenproject. ... Read up on paravirtualisation > 5 > oVirt. ovirt. ... Possibly now dead - from Red Hat - may be the basis for RHV below. > 6 > Red Hat Virtualization (RHV) Red Hat Virtualization. ... > 7 > GNOME Boxes. GNOME Boxes. ... Native virtualisation inside modern GMOME > 8