A virtual machine (VM) is a guest Operating System running in a completely isolated environment within a normal host operating system. Modern virtual machines are implemented with either software emulation or hardware virtualization or (in most cases) both together.

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CPU usage of KVM

I have a linux host with 4 KVM linux guests. All the guest are pretty much idle, having a load of <0.1 inside the guest. Now, if I do a top on the host, each KVM process is using something about ...
2
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2answers
6k views

How to enable Virtualization AMD-V Aspire one AO725 from BIOS or otherwise

I'm try to use the virtualbox to visualizer the system of 64bits but the error that get is: La aceleración VT-x/AMD-V ha sido habilitada, pero no es funcional. Su sistema invitado de 64-bit fallára ...
5
votes
2answers
898 views

Do I need acpid in a virtual machine?

I'm always wondering if power management facilities in a virtual machine is necessary? i.e acpid. And I'm not sure if they still function in a virtual machine.
2
votes
1answer
1k views

How to achieve the effect of chroot in userspace in Linux (without being root)?

The goal is to install and run programs in a displaced (relocated) distro (whose / must not coincide with the global /) inside a host Linux system. The programs are not adapted for using a different / ...
5
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1answer
319 views

Running one OS per core

I'm interested in using a COTS board like the Wandboard for a project. On one hand I'd like to use something like Ubuntu for user interaction, sounds, TCP/IP stuff, etc. But I also need an RTOS like ...
2
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2answers
419 views

Can I have a bridged interface without an IP?

I have 2 NICs: eth0 & eth1 on a host OS which runs some VMs (LXC) under it. The hosts eth0 is connected to a private network and configured as the primary interface. The hosts eth1 is connected ...
2
votes
1answer
5k views

How to get past “Loading Initial Ramdisk” hang after going from x86_64 to i686 cpu

Long story short, I have a Ubuntu 12.04 64-Bit Server setup as a virtual machine with VirtualBox (4.1.18). I migrated the guest machine from an AMD chipset (a gaming machine) to an Intel Xeon (server ...
3
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3answers
2k views

Linux / JVM - OutOfMemoryError: unable to create new native thread

I have a memory problem with a Linux server (CentOS). It is a VM. Below is the context. It has 70Gb of RAM. There are 2 tomcat running on it. One tomcat is given a heap of 13Gb and the other one a ...
0
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1answer
209 views

Fedora 18 Live CD is hanging on boot

When I boot up Fedora 18 (Fedora-18-x86_64-Live-Desktop.iso) in a Virtual Machine, I just get this screen: I've verified the SHA sum, and I've tried starting it up in "basic graphics mode", yet I ...
3
votes
2answers
648 views

How to add a ms-dos partition table to a loop device?

I recently made a dd from a disk partition. I want to use it as a disk in a virtual machine. I can't because the disk has no partition table. Can I had a partition table to a loop device? how? ...
2
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2answers
260 views

Install the same 64-bit packages as a 32-bit Xubuntu installation

I have been using a virtual machine (Xubuntu 12.10, with VMWare on a windows host) for all my programming work, which I am trying to transition from a 32-bit install to a 64-bit install. I am hoping ...
2
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0answers
280 views

Network in LXC not forwading through a bridge

I've got an LXC container, on the host I've got a bridge between the LXC container and eth0. The LXC container can ping it's Host 10.1.0.5, but can't ping the gateway of 10.1.0.2. The host is able to ...
2
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1answer
2k views

Do USB emulators exist for Linux?

I'm looking for software that lets me have many virtual USB drives on my Ubuntu installation. I want them to be seen by virtual machines in VirtualBox so I can do backup operations. I need the drives ...
2
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4answers
1k views

Install Arch Linux to external hard disk using a Virtual Machine?

I have an external hard disk and I want to install Arch Linux on it. Since I'm a complete beginner I want to have access to the online the documentation. As the title states, it is possible to install ...
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3answers
237 views

Can I install ubuntu on a Virtualbox image and use it anywhere?

I am wondering if I install ubuntu once on a virtual machine running inside virtualbox, could I then use it as a portable OS and launch it from virtualbox on any machine? Or would I have to match the ...
1
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1answer
144 views

Help understanding interfaces in Backtrack

I am fairly new in UNIX and have recently installed backtrack on a VMWare box on my machine and I am trying to use DHCLIENT command but am having trouble in understanding the interfaces. I am ...
3
votes
1answer
64 views

memory buffering in virtual machines

Is there any point to doing disk buffer caching in a virtual machine, if the hypervisor OS is doing it? I wonder if buffering in the VM will just waste memory that could be better allocated to VM use, ...
2
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2answers
970 views

Everything works except Fedora

I'm taking an Operating Systems class online for college. It requires us to have a copy of Fedora 13, provided by our instructor, running on a virtual machine. On my machine, it boots to a message ...
1
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1answer
822 views

Sending Emails from bash script in Solaris VM

I am trying to send emails using the following bash script: /bin/mail -s "#subject" "$emailto" < "$message" It works fine on my local machine but does not work on my VM. I looked it up and read ...
2
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0answers
407 views

How to manage 2 vm using upstart?

I use an upstart script to monitor a vm and respawn it when it gets killed. I would like to simulate a failover by doing the following. Create a clone of the VM1 say VM2. When either of them is ...
17
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1answer
4k views

how to send CTRL-ALT-Fn to virtual box guest Linux?

This should be a simple question: Host OS: Arch Linux Guest OS: Arch Linux (GNOME) How can I send Ctrl+Alt+F1 to my Guest Linux OS?
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0answers
699 views

Xen is unable to use URL's to install CentOS

I can't seem to use URL's when using the netinstall for CentOS, I'm installing CentOS on a Xen VPS. I keep getting this error in the terminal window, when I use the URL: ...
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1answer
673 views

vmstat on virtual machine and large values

Hi I'm using vmstat to track machine performance during some tests (jmeter). This is virtual machine running on a big machine where lots of other virtual machines are installed (about 20 virtual ...
2
votes
2answers
3k views

Why does dhclient fail with my ISP's DHCP server on a virtual interface?

Recently I switched from a T1 to a residential cable service (Comcast). I have a virtual machine (XenServer 5.6) running Debian 6.0.6 that is acting as the default gateway for my home network, but for ...
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1answer
272 views

Xen error on CentOS

During the creating of a new virtual server in xen using this command xen-create-image --hostname=minecraft.koanhosting.com --ip 87.98.249.146 --install -method=debootstrap But I keep getting this ...
3
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2answers
54 views

Running -march optimized software on another architechture?

I'm running an Athlon64 server with LFS and would like to have a local copy of the server in a virtual machine for testing purposes and building software. My PC uses an i7 and the existing server ...
1
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1answer
2k views

Guide to installing Xen on CentOS 5.9 (That is still valid)

I need an idiots guide to installing Xen Hypervisor on CentOS 5.9 We attempted to install it on 6.3 before, but completely failed, so we reverted to 5.9 to see if we had more luck. We had issues ...
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votes
1answer
4k views

Is it possible to install KVM On A VMWare virtual machine? If so, what are the steps?

I want to understand how to use KVM in CenTOS. At the moment, all I have is a VMWare ESX 5.x server to use. Is there a way to get KVM working on a system that is running on VMWare? Essentially, a ...
2
votes
1answer
486 views

How to use a backup in OpenVZ

I have a backup (.tgz file) that is an openvz virtual machine. i followed this article and i setup an openvz container but how i will use my backup file? EDIT: i found the tool ovz-web-panel (i am ...
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0answers
564 views

Problem getting Fedora to run in VirtualBox

I'm using Ubuntu 12.04 64-bit, trying to get Fedora 18 64-bit to run in the Oracle VM VirtualBox. I've got VirtualBox installed (via the .deb package available from the official site,) and I got the ...
3
votes
1answer
250 views

How to enlarge existing file to specific size

I have hdd.img file, which I user as HDD for my virtual machine, but it's size is too small, how can I enlarge it? There is one method, something like: dd if=/dev/zero ds=10GB count=8 >> ...
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2answers
330 views

Create a CentOS Guest img over Ubuntu

I want to create a basic CentOS 5.8 system from scratch. for now i build my own img for Ubuntu Guest (debootstrap), my host is a Ubuntu 12.04.1LTS but I don't know how to make for a CentOS, is ...
0
votes
1answer
6k views

“client denied by server configuration” with “AllowOverride All”

I've installed CentOS 6.3 with Apache 2.2 on a VM. I'm trying to set up a LAMP stack with these VirtualHosts: localhost loads the path /var/www/html/ lcl.mydomain.com loads the path ...
4
votes
2answers
796 views

disabling ssh session expiration

I am installed Ubuntu on Virtual Box, and use xshell (a remote terminal application) to ssh to ubuntu. when I hibernate computer during night, after powering it on, the session is expired and I should ...
1
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1answer
158 views

High-latency VM-centric workstation, vs. low-latency, (but, hack-ish) configuration for Oracle 11g

tl;dr Low-latency native (i.e. VM-less) development workstation vs. higher latency VM-centric workstation? Hey StackExchange, I'm unsure of whether or not I should be using a VM for development, as ...
4
votes
2answers
871 views

Does FreeBSD support network virtualization like Crossbow?

Does FreeBSD support network virtualization like Solaris Crossbow? I've tried to follow the VImage links from the FreeBSD wiki page, but the links are mostly dead. If VImage is no longer part of ...
0
votes
1answer
784 views

How to install FTP server on Red Hat VM?

I have a windows machine and I need to transfer files from my machine to another Linux virtual machine which I have created. How do I install a FTP server on those VM's to transfer files via FTP ...
4
votes
3answers
2k views

Openstack for home cloud hosting

I am experimenting with a couple of technologies that I soon may have to use at work. So for now, I was thinking about duplicating the environment which I may have to create for my office at home so ...
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2answers
998 views

Linux guest VM on mac host - Keyboard

I use a Mac as a development box, but am slowly transitioning to Linux. So I am spending the majority of my time in the Linux guest VM while working. But I still spend a fair amount of time in Mac ...
2
votes
3answers
1k views

How to access a KVM virtual-machine?

I've created a KVM VM using virt-install. There is an image file in the directory /ssd/kvms. How do I access the virtual machine and turn it on? Do I need to assign an IP address, and if so, how do I ...
3
votes
0answers
2k views

PCI passthrough with Xen

I am trying to run Windows XP in a Xen DomU virtual machine with a PCIe device, for which there are no Linux drivers, being passed through from a Debian Squeeze Dom0. My hardware supports ...
2
votes
1answer
716 views

Can QEMU/KVM+OCFS2 be configured to punch holes in sparse image files when files are deleted in the guest?

I'm using sparse raw image files for guest VMs and OCFS2 on the host (local-only, not clustered) for the reflink feature. I understand from Googling around that OCFS2 is one of the filesystems that ...
2
votes
1answer
2k views

VBoxManage: Error: Can't be used as the requested device

I used the soluton from this thread but always i get VirtualBox error: The medium 'lvol.vmdk' can't be used as the requested device type (0x80004005) I've tried all controllers SATA, SCSI, IDE and ...
3
votes
0answers
276 views

Setup Cloudmin on Centos installed in LVM

I installed CentOS 6 with default LVM partition pattern. according to this pattern Can I use Cloudmin and store KVM Disks in LVM as Logical Volume? I think Cloudmin requires creating new logical ...
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0answers
225 views

not all initrd.img's are born equal?

I am trying to get a Red Hat 5.8 box booting via pxe. The box is a virtual machine on ESX5.0 it has a Paravirtual SCSI Controller and VMXNET3 network driver. Now these drivers do not come default in ...
4
votes
1answer
9k views

What is the difference between virbr# and vnet#?

I am running KVM on RHEL6, and I have created several virtual machines in it. Issuing ifconfig command to the host system command line shows a list of virbr0, virbr1... and vnet0, vnet2... Are they ...
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2answers
3k views

Why doesn't eth0 get an ip address when set up in a bridge?

I'm trying to understand how dhcp for IPv4 is used with bridging. eth0 is configured to be in br0. This is working just fine but only br0 gets a dhcp lease, while eth0 doesn't. Both are configured ...
36
votes
6answers
70k views

File permission issues with shared folders under Virtual Box (Ubuntu Guest, Windows Host)

I am using Ubuntu on Virtual Box and I have a folder which is shared between the host (Windows) and the VM (Ubuntu). When I open any file in the share folder in Ubuntu, I can not change it as its ...
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vote
1answer
606 views

How to get the cloned guest connected to the Internet?

I made a clone of a VM(running a version of Centos 6) on KVM, but the clone wouldn't connect to the Internet. Issuing ifconfig shows no interfaces but the lo. Interestingly, the original system can ...
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1answer
108 views

How to boot a system in a second HD but runing the system in another one?

I have two computers, but the old one is not working well. So I'd like to install the old hard disk on the new computer. I know how to do this and I know how to access the data from sdb. But I have ...