Can looking glass be used to control a VM from another VM?

Software & Operating Systems Linux
1

if i have 2 VMs, one using windows and the other using Linux, can i use looking glass to control the windows VM from the linux VM?

if this is possible, is there any way for the Linux VM to also get the windows VM audio without using the network? similar to using pulseaudio to get the windows VM audio on the host, but i want it to go another step: into another VM.

2

Looking Glass copies the contents of the frame buffer of one physical guest GPU to the physical host GPU. There is no “control” functionality.

If you just wanted to listed to Windows audio in one VM, while you are working in a different VM, I’d pass a USB card to the guest and then plug a $10 USB sound card & speakers into the USB card.

3

@mathew2214
If you mean VM to VM looking glass functionality, then yes it is possible! Don’t get your hopes up, it’s quite experimental and unsupported at this point. Also there’s bandwidth issues too, so performance is bad and this may or may not be solvable with current hardware.

4

Incorrect, performance is as good as Host to VM

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5

Neat, glad to hear you found a solution.

6

I’m trying to think of reasons why you would ever want or need to do this but I’m at a loss.

7

Well here are some.

The TreadRipper is overkill for a general purpose PC, however it makes an excellent SOHO server. Instead of running a desktop PC in parallel to the server I run a virtual machine on the server as my desktop environment, this is both for energy savings, security and safety due to the level of isolation provided. However I still like my games, so I also run a Windows VM for gaming, again on the same host.

In all I am running 6 VMs on the one PC:

  • Linux Wokstation
  • Windows 10
  • Remote backup server
  • Asterisk PBX server
  • HTTP Development Server
  • GitLab Server

I have 42.2TB of attached storage:

  • 6x 4TB SAS drives in a JBOD array
  • 4x 4TB Internal SATA disks
  • 1x 1TB Samsung 970 Pro NVME
  • 1x 1TB Samsung 840 EVO SATA
  • 1x 250GB Samsung 850 EVO SATA

By only allowing indirect access to these disks it provides security though isolation and fine grain access control.

Also the host is running OpenVSwitch which is working in tandem with a managed switch to isolate VMs like Asterisk into a DMZ VLAN.

And finally, when I want/need to upgrade/update/reboot the Linux Workstation, I don’t need to reboot the entire machine, keeping all the other VMs up and running.

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8

I understand the need for Virtual machines that’s not what I’m asking. I’m questioning the need to ever run a VM inside of a VM for anything other than a quick trial or for fun.

I would also add that you are depending waaaay too much on a single machine.

9

That’s not what the OP asked about, it’s running two VM’s in parallel and controlling one from the other. Running VM’s inside VM’s is possible and is used when evaluating/debugging hypervisors, but even still, it’s not what this thread is about.

Edit: I misread the OP, you are dead right, he is running a VM inside a VM… which IMO is pretty pointless also.

Everything it hosts is not mission critical and as such in this scenario it is perfect for the job. Everything mission critical is housed on real servers with ECC RAM in datacenters, in HA clusters.

Like I said, this is a SOHO server for a power user, or small team of users.

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