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On Tuesday, June 16, 2020 11:08:23 PM CEST n952162 wrote: |
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> On 06/16/20 22:36, J. Roeleveld wrote: |
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> > On 16 June 2020 21:07:56 CEST, n952162 <n952162@×××.de> wrote: |
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> >> On 06/10/20 15:19, n952162 wrote: |
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> >>> I updated my system and now characters typed into vbox over ssh are |
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> >>> not echo-ed until *after* a CR is entered. |
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> >>> |
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> >>> I diffed the stty output, to see if I could spot anything: |
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> >>> |
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> >>> 10~>cat /tmp/sttydiff |
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> >>> 2,3c2,3 |
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> >>> < rows 37 |
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> >>> < columns 100 |
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> >>> --- |
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> >>> |
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> >>>> rows 44 |
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> >>>> columns 88 |
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> >>> |
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> >>> 21d20 |
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> >>> < discard = ^O |
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> >>> 23c22,23 |
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> >>> < min = 1 |
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> >>> --- |
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> >>> |
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> >>>> discard = ^O |
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> >>>> |
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> >>>> min = 1 |
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> >>> |
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> >>> 30c30 |
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> >>> < hupcl |
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> >>> --- |
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> >>> |
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> >>>> -hupcl |
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> >>> |
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> >>> 36c36 |
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> >>> < brkint |
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> >>> --- |
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> >>> |
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> >>>> -brkint |
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> >>> |
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> >>> 48,49c48,49 |
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> >>> < imaxbel |
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> >>> < iutf8 |
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> >>> --- |
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> >>> |
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> >>>> -imaxbel |
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> >>>> -iutf8 |
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> >>> |
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> >>> Also, the font seems to be screwed up, because the last line of the |
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> >>> window only shows the top half of the line. |
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> >>> |
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> >>> Anybody else encounter this or know what's wrong? |
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> >>> |
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> >>> Vbox seems to work okay when run locally, on the machine it's |
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> >>> installed on. |
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> >> |
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> >> I think this is resolved, kinda. |
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> >> I just discovered that if I turn off the vbox menu bar, the command |
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> >> entry line works properly again, both in X-less console mode and in X. |
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> >> |
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> >> Settings -> User Interface -> Enable menu bar (disable this) |
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> >> |
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> >> I've always had that menu bar, and need it, so something got |
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> >> changed/broken, and I still have a problem, but at least now I don't |
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> >> have to enter commands in blindly. |
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> > |
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> > Are these Virtualbox VMs critical? |
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> > If yes, I would suggest migrating them to a more reliable virtualisation |
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> > technology. |
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> > |
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> > I do not consider Virtualbox suitable for anything but a desktop based VM |
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> > method for a quick test or simulation. |
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> > |
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> > Gor anything serious, I would suggest Xen, KVM or VMWare. |
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> > |
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> > -- |
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> > Joost |
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> |
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> Well, no, they're really not critical, but your comment surprises me. |
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> I've been using vbox for years, on various assignments, and never |
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> encountered anything else. Can you say a word or two to that, or |
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> provide a URL? Which free vm is "the best"? |
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|
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I never bothered bookmarking URLs about this, but can elaborate on my |
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reasoning and experience. |
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|
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Virtualbox is a nice product and I do use it when it is convenient. It is |
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perfect for quickly starting a VM to test something. It integrates nicely with |
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the desktop to be able to quickly copy/paste data across and also easy to |
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connect to the filesystem on the host. |
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|
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This also mentions the reason why it is NOT suitable for actual production |
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use. It is a virtualisation tool for a desktop. |
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|
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If you want your VMs to run as fast and stable as possible, you want the host |
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to be as minimal as possible. This means: |
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- it runs headless (no GUI, just text) and the host has only 1 task: Run VMs. |
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- it doesn't contain anything else (only exception is stuff for monitoring) |
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|
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Virtualbox does not (afaik) support block-devices for VMs. It only supports |
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file-based disks. This is fine as it allows you to "quickly" move these to |
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different storage. But it adds another layer between the hardware and VM |
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(filesystem on the host) which adds it's own write-caching and potential |
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corruption (I have had this on several occasions). |
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|
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The virtualisation systems I mentioned in my previous email (Xen, KVM, VMWare) |
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all support block-devices and sit as close to hardware as is possible. In the |
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case of VMWare, I am talking about the server product, not the desktop |
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product. The VMWare desktop product has the same problems as VirtualBox. |
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|
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As for which free one is best, I am reluctant to answer specifically as both |
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Xen and KVM are good. |
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|
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Personally, I use Xen. I have been using it since one of the 2.x versions and |
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KVM didn't exist back then. |
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Xen has the hypervisor in a small "kernel" and the host runs as a VM with full |
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privileges. You can add additional privileges VMs to provide storage, further |
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seperating tasks between VMs. |
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Citrix also provides a free version of their Xen-product which can be managed |
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remotely, but their remote-tool is windows-only last time I checked. I run Xen |
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on top of Gentoo and manage everything from the CLI. |
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|
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KVM runs inside a Linux kernel and this instance automatically is the host. (I |
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don't know enough to properly compare the 2, there are plenty of resources |
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about comparisons online, most are biased to one or the other) |
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|
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Both Xen and KVM can be managed with other tools like virt-manager. I don't as |
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I don't like the way those tools want to manage the whole environment. |
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|
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As for use of these systems, when only looking at companies where I have |
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experience with: |
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|
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- VMWare is often used for virtualising servers |
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- Xen (Citrix) is often used to provide Virtual Desktop to users |
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- KVM is used by most VPS providers |
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- Virtualbox is used for training sessions |
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|
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I have not come across MS HyperV outside of small businesses that need some |
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local VMs. These companies tend to put all their infrastructure with one of |
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the big cloud-VM providers (Like AWS, Azure, Googles,...) |
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|
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-- |
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Joost |