What is the virtual machine backdoor?

I fell on what we call a back door virtual machine by reading the following blog post: http://virtualfoundry.blogspot.com/2009/04/protect-console-virtual-firewall.html

He says the following:

While you're there, go ahead and disable the virtual computer is backdoor by adding this directive:

monitor_control.restrict_backdoor = 'true '.

What is this backdoor? Should I add this command to all my virtual machines?

Thank you

The backdoor is a channel of communication between the client and the hypervisor.  It allows guests to enjoy the hypercalls on the hypervisor.   Despite the scary name, it is not a security issue in and of itself, although there is always the possibility a hypercall implementations allows a kind of safety operating.  The backdoor of VMware is implemented as an operation of e/s to a specific port address.  The games instructions VT - x and AMD - V also provides a hypercall mechanism, but we still use the inheritance mechanism, because it is supported by all of our hypervisors, regardless of the underlying implementation.

The 'monitor_control.restrict_backdoor' configuration option does not disable the door entirely.  As its name suggests, it restricts the use of the backdoor.  In particular, they only allow the guest to use the backdoor when the IOPL prompt > = his CPL.  In general, this means that the client must be running code monitoring, such as the core OS guest, clocked at CPL 0.  (There are some notable exceptions, such as Linux X server, which takes place in CPL 3 with 3 IOPL.)

When you run a nested VMs, the backdoor should be limited in the external virtual machine if you want to be able to make the inner virtual machine to the hypervisor inner hypercalls.  Otherwise, hypercalls made the inner virtual machine will be provided by the external hypervisor.  If you don't care to install VMware Tools in the virtual machine internal, you don't have to restrict the backdoor into the external virtual machine.

Tags: VMware

Similar Questions

  • Oracle installed on the virtual machine

    Hello world!

    In one of the server, Oracle is installed on a virtual machine.

    I have to make a change in the way I set up the file settings or something else to improve performance?

    What a difference, is to have the Oracle in the area directly compared to what in the virtual machine?

    Hope to hear some tips.

    Thank you. :)

    Nith

    user645399 wrote:
    Hello world!

    In one of the server, Oracle is installed on a virtual machine.

    I have to make a change in the way I set up the file settings or something else to improve performance?

    What a difference, is to have the Oracle in the area directly compared to what in the virtual machine?

    There is no difference running Oracle in a virtualized environment or on a box. For the performance gain, the same number of steps are necessary as normally are required. Read the guide to performance optimization of Oracle doc site corresponding to your version of db http://tahiti.oracle.com.

    HTH
    Aman...

  • What windows key you use to activate one of the virtual machines on my Hyper-V on Windows Server 2012 R2 Std

    I installed my Hyper-V role and now wants to activate one of the virtual machines, but the key is not recognized.  Should what key I use?

    Hello

    Your question is beyond the scope of this community.

    I suggest that repost you in the Forum of Hyper-V on Technet.

    https://social.technet.Microsoft.com/forums/WindowsServer/en-us/home?Forum=winserverhyperv

    Or:

    TechNet Server forums.

    http://social.technet.Microsoft.com/forums/WindowsServer/en-us/home?category=WindowsServer

    See you soon.

  • What is the interval of time between the virtual machine Linux and ESXi host synchronization?

    I have ESX5.0 with a centos6 installed on this linux virtual machine.

    After the installation of vmware for Linux virtual machine tools, I activated the time synchronization between the virtual machine linux and ESXi host through vmware-toolbox-cmd.

    I wonder what is the interval of time between the virtual machine linux and ESXi host synchronization? If I quickly time OS system, when the OS system time will sync back to the ESXi host?

    According to http://www.vmware.com/files/pdf/techpaper/Timekeeping-In-VirtualMachines.pdf:

    By default, the demon checks the guest only once per minute operating system clock.

    However, depending on whether the guest is behind or in front of the result is different. So, please read the section "periodic synchronization" (at least) in the document mentioned above.

    André

  • "this host is not no matter what networks of virtual machine, or you don't have the permission to access ' ESXi V4

    I'm sure I'll be stupid on this one, but what does do to ensure that networks of virtual machine?  I get this message when I look at network/properties of a VM adapter 1.

    When the virtual computer runs, my network card think the cable is disconnected.

    I went to the host properties and of course there is a 'Virtual Machine port group"and a"VMKernel Port", both connected to my physical card.

    I don't see anything obvious on the network are disabled or anything like that.

    Please give me a hint?  Virtual machines to run it, but without any network connectivity.

    Thank you

    Joe

    I had this on the virtual machines that I moved from VMware Server 2.0. I found that there is no entry for the "ethernet0.networkName" in the .vmx files Server 2 (and probably Workstation) do not seem to care and connect ethernet0 to the first configured network. ESXi 4 all confused. So for me, the solution was to add

    ethernet0.networkName = 'Hand Lan'

    for each file .vmx before adding them for ESX. If you have already added the machine, you will need to remove it before you edit the .vmx file.

  • Java with Minecraft error "error: could not create the Virtual Machine Java.»

    When I try to open Minecraft SP, it won't let me open and there is a message saying:

    "Error: could not create the Virtual Machine Java.".
    Error: A fatal error has occurred. Program will exit. »
    How can I solve this problem?

    Hello

    What is the operating system installed on your computer?
     
    You can ask your question on the Minecraft forums for assistance. Check out the following link.
    http://www.minecraftforum.NET/viewforum.php?f=1002
  • Windows XP Home Edition (Version 2002) include SP1 is the Virtual Machine for Java (MSJVM) installed on this and future Service Packs Microsoft remove it?

    While the installation of Microsoft DirectX 9.0 c on my Windows XP Home Edition (Version 2002) operating system (not sure if the 2002 version in it's original state included SP1), EULA (EULA) provided the contract included a paragraph stating that "ONLY in regards to THE VIRTUAL MACHINE MICROSOFT FOR JAVA, YOU ARE ONLY ALLOWED to INSTALL THIS OS COMPONENT ON A MACHINE THAT CONTAINS A ALREADY the VERSION OF THE MICROSOFT JAVA VIRTUAL MACHINE". Assuming that the MSJVM was included with Windows XP Home Edition (Version 2002), I advanced and accepted the EULA. I then downloaded and installed Windows XP SP2 and SP3, but wasn't sure whether SP2 and SP3 removed the MSJVM in any point. However, research on the question, I discovered the site "FAQ of Transition MSJVM" (updated May 7, 2004), who answered the question: ' if I install Windows XP SP1a or later, it will remove my current MSJVM? " with "No, the operating system upgrade will not remove a MSJVM existing on the computer" (http://www.microsoft.com/about/legal/en/us/interoperability/java/faq.aspx). However, I can't find any instance of it on my computer.

    So my questions are:

    1. Windows XP Home (Version 2002) Edition include SP1?
    2. The MSJVM is installed on this version?
    3. SP2 or SP3 removes the MSJVM in any point to?

    Hi Chris,

    Your Windows XP question is more complex than what is generally answered in the Microsoft Answers forums. It is better suited for the IT Pro TechNet public. Please post your question in the forum TechNet for assistance:

    http://social.technet.Microsoft.com/forums/en/itproxpsp/threads

    Hope the helps of information.

  • the virtual machine monitor driver required by the virtual machine is missing

    Hello
    After you install virtual pc xp2 and when I run this program I got this messege (the virtual machine monitor driver required by the virtual machine is missing)
    What is the answer

    Hi jameelaswad,

    The question you have posted is better suited in the forums of Virtual PC. Please see the following link for more information.

    Windows Virtual PC / Windows XP Mode Forum

  • 'Fail forward' for Ports on the virtual machine

    We have a customer who will be centralizing the unit with about 250 users at remote sites (4 Sites, 1000 Subscribers, they have currently a unit break at each site and want to centralize). Each site will have its own cluster of CM. I'm thinking about what I could do failure network SCOPE. Of course, each site will be fine IPT wise because they have their own cluster of CM, but VM will be declining. I think I watered but if there was a way to "transmit failure" or something on the VM ports on the PSTN to maintain the work of the virtual machine. (Of course carrier must support ISDB).

    Someone at - it works in this or thought about it?

    Andrew Dignan... If the carrier supports RDINS of course

    The connectivity of voice mail for Cisco CallManager chapter of the Cisco CallManager System Guide:

    "Inter-classes Interfaces A Cisco CallManager in a cluster can provide access to a voice mail system in another cluster, if the administrator provides the voicemail number on the trunk driver inter-classes. Voicemail systems can leave messages and sets the flags of message waiting for devices other clusters if clusters are connected by trunks QSIG. »

    This applies to any system of virtual machine. With the unit, you have of additional capacity to save ports across multiple clusters so to provide MWI without ICTS as QSIG.

    Hope this helps,

    Eric

  • I get an error "the disk hard virtual parent is in a saved state. Discard the saved state or stop the virtual machine and try again. "during the installation of XP mode.

    I have Win7 Pro SP1 x 64.  I downloaded WindowsXPMode_en - us.exe (from Microsoft downloads) and run it.  The installation seems to work OK (I've specified a different location for the parent virtual hard disk file).  Then, installation happening and I provide the information requested (name of user and password for the XP Mode), updates Windows and OK to the issue of sharing.  The installation program then reports the following error:

    The disk hard virtual parent is in a saved state.  Discard the saved state or stop the virtual machine and try again.

    I get the error even if I try manually configure XP Mode (use the Setup Wizard).  I downloaded the installer XPMode (3 times) and reinstalled several times, always with the same result.  If it helps, I can't locate anywhere .vsv file.

    Any idea what's going on?

    Original title: XP Mode Setup error

    Hi smithnr10,

     

     

    You must post your question in the TechNet forums because it caters to an audience of it professionals.

    To do this, you must consult the link-

    http://social.technet.Microsoft.com/forums/en-us/w7itprovirt/threads

     

    Hope this helps!

  • Metric of availability for the virtual machine

    Hi all

    I know that stands metric Uptime to know for how long the virtual machine worked without a reboot, but I want to understand what is the best value of this metric?

    If I put the time in a dashboard, when is red, yellow and green?

    Thank you.

    Availability is not defined in a range or hundreds.

    What exactly you're trying to find availability? Want to know how long the machine is for?  It's a number that rises and sinks to zero when you restart. There is no transition between different values such as CPU utilization or memory.

  • "Unable to connect to MKS" when connecting to the virtual machine shared

    Hello

    I have a handful of Shared VMs Im trying to access remotely with VMware Workstation Pro 12 (same version on the client and the host - two Windows 10 machines). I am able to connect to the host that shares virtual machines, I can see all the virtual machines shared, open the virtual machine (as in it opens in a tab within the workstation) and virtually no action on the virtual machine including all power options, instant, change settings, etc.. The problem is that if I turn on a virtual computer (or connect to an existing virtual machine under tension, I get the following error and Im not able to access the actual console since it remains as a black screen.

    Unable to connect to the MKS: (name of user and password) Login incorrect.

    I also noticed that on the client Windows Event Viewer is to launch the following warning events at the same time that the error in the Workstation has been lifted - Im not seeing any on the host are thrown.

    vmware1.png

    vmware2.png

    I've seen a lot of posts here with users who run the question and he usually ended up being a network problem. I turned off the Windows Firewall on both machines, checked ports 443 and 902 listening on the host and Im in telnet from the client to the host on port 902. I also saw another suggestion for updating the client Windows hosts file to include [host name] [IP address] and [FQDN of the host name] [ip address], but this subject seems not helped either.

    Suggestions in this regard does not happen what keeps or where to find more information about the cause?

    Thank you!

    Post edited by: Tim Graffam

    Thank you for using the workstation. I think that this will solve your problem.

    Unable to connect to the MKS: (name of user and password) Login incorrect

  • Convert the virtual machine to another pc, but... Operating system not found?

    I use VMWare converter to convert a PC Esxi Esxi (on IBM X3650M4) comments, when to start guest VM of the PS, it displays "Operating system not found", there is no hard drive computer virtual on the BIOS of the virtual machine, what happened?

    So your source host where this virtual machine was originally executed is ESXi 5.0, is?

    Please right click on your VM, go on "Change settings" and also view this screenshot and/or join the VM's vmx file here please.

    What is the guest in this virtual machine operating system?

  • Expand or move the virtual machine to another partition / hard disk

    I tried to expand my 90 GB disk but nothing changes, i.e. the virtual machine is still to 60 GB. I have VMware Fusion 6 (Mac/Windows 10) and my VM is monolithic mode. In this true HD, I even 50 GB free and I can't increase the amount again in an attempt to rectify this problem and I can not to decrease either. I thought to change the location of the virtual machine to another partition/hd with more space, but I don't know how. So I need little help to choose and implements one of the solutions below:

    - or regularise space for the new amount

    - or move the virtual machine (vmdk) to an another partition/HD

    - or to convert monolithic mode to 2 GB split

    What is the best solution?

    Thanks in advance

    It's help me;

    Resize a Windows Partition with disk management tool

    When you maximize your virtual hard disk, you must also expand partition of your guest operating system to take advantage of the extra space.

    Fusion resizes the partition of the guest operating system when you resize the virtual hard disk. If you hold the Option key when you click apply to resize the drive, you can manually resize the Windows partition. For Windows 8, Windows 7 and Windows Vista you can use the operating system's disk management tool to resize a partition.

    Prerequisites

    Check that your virtual hard disk is large enough to accept the increase in the size of the partition. See resize a hard disk.

    Procedure

    1 right click on computer and select Manage.

    2. double-click on storage.

    3 double-click disk management.

    4 in the list, right click on the partition to expand and select Extend the Volume.

    5 follow the prompts to resize the partition and click complete and the question of the partition in the disk management pane displays its new size.

    6. close the computer management window

  • Error: "VMware Workstation has suspended this virtual machine because the disk on which the virtual machine is stored is almost full."

    I get this error message:

    VMware Workstation has suspended this virtual machine because the disk on which the virtual machine is stored is almost full. To continue, free 1.3 GB of additional disk space.

    I read up on the subject and found that I have to re size a partition. Anyone know what it could be? I can't find anything that looks like it has something to do with VMware. Does anyone know what size and what file system is it?

    My OS:
    Tumbleweed OpenSUSE x 64

    Thanks in advance

    On more creative, my home and root file systems were not extended to my full disk space :^)

Maybe you are looking for