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)?
I applaud someone wanting / willing to read a book ;-) (I'm smiling, but I am serious.) I also applaud the recommedation (in a later reply to the original email) for an online book (at least one doesn't have to pay for that book (iiuc)). But the entire concept of needing a book to understand what the OP needs to know about or to use VMs just bothers me. Changing subjects slightly, I've spent a few calendar months (too many) and manhours (not all that many, but still too many) trying to dig into what I feel I need / want to know about ssh (and more specifically, the Certificate Authoriity, public key, and password methods of authentication). I tried reading a fair quantity of online (or on machine -- e.g., man pages) documents on the subject and just haven't found what I need or want to know (that is, without contradictions, obscurities, (significant (to me) omissions or confusing (in some cases ambiguous) terminology. 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. 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.) Maybe I'm just getting old (despite my plan to start getting younger at each birthday since the one at which I would have turned 65 ;-), but it (ssh in my case) just seems harder than I would have expected (especially considering how easy it can be to use, especially with "just plain" password authentication. Anyway, maybe I just felt the need to rant. 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. There is probably little need to reply -- mainly just a rant I guess. Have a good day! 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 * 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. ... 2 Linux KVM. KVM. ... 3 Microsoft Hyper-V. Hyper-V-Manager. ... 4 Xen Project. Xenproject. ... 5 oVirt. ovirt. ... 6 Red Hat Virtualization (RHV) Red Hat Virtualization. ... 7 GNOME Boxes. GNOME Boxes. ... 8 ProxMox. Proxmox. Top opensource virtualization software for Linux www.fosslinux.com › Downloads </quote> -- rhk If you reply: snip, snip, and snip again; leave attributions; avoid HTML; avoid top posting; and keep it "on list". (Oxford comma included at no charge.) If you change topics, change the Subject: line. Writing is often meant for others to read (legal agreements excepted?) -- make it easier for your reader by various means, including liberal use of whitespace. If someone else has already responded to a question, decide whether any response you add will be helpful or not ... A picture is worth a thousand words -- divide by 10 for each minute of video (or audio) or create a transcript and edit it to 10% of the original.
