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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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 ...
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1answer
136 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 ...
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1answer
58 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, ...
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2answers
918 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 ...
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1answer
706 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 ...
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0answers
376 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 ...
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1answer
3k 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
657 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
586 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 ...
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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
258 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 ...
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2answers
53 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 ...
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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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1answer
3k 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 ...
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1answer
422 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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532 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 ...
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1answer
234 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
305 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 ...
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1answer
5k 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 ...
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2answers
744 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 ...
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1answer
155 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 ...
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2answers
776 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 ...
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1answer
689 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 ...
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2answers
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
874 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 ...
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3answers
994 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 ...
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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 ...
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1answer
659 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 ...
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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 ...
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253 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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218 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 ...
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1answer
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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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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 ...
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6answers
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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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1answer
512 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 ...
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0answers
466 views

Connect to a VPN from a Linux Virtual Machine

I am running an Ubuntu distro inside a VMWare virtual machine with a bridged connection on a Windows 7 host. What I am trying to do is to have the virtual machine connect to a VPN, but I'm not having ...
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2answers
3k views

Fastest remote X from Windows

I have the following set up: |-----------------| |---------------| | Windows | LAN (or VPN) | Linux box | | (local machine) | ...
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1answer
2k views

How to force Debian to wait for DHCP

I am running Debian squeeze in a virtual machine (VirtualBox). The machine has two interfaces: eth0 in "Host-only" mode so that the machine is accessible from the outside; and eth1 in "NAT" mode so ...
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1answer
2k views

Does quiesce exist for Linux?

Quiescing a file system allows you to make a backup of the database while it is still running and other programs and their data as well. The application generally needs to be notified of the quiesce ...
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1answer
521 views

Make box only communicate on lan only?

I am running a VM with Debian as the guest OS (I can choose another distro). It has nginx running along with some other software. Some of the software tries to make outgoing connections (for example ...
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3answers
459 views

Physically break into box? (Memory & disk)

I have a VPS. I might be able to encrypt my partition but I havent tried. My VPS company I believe can reset my root password although the only SSH key I see is my own. With all my data I have it ...
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1answer
1k views

kvm doesn't load Windows 8

I'm launching kvm with the following parameter: kvm -m 2g -smp ncores=2 -hda disk.img -cdrom win8.iso My CPU has VT support and enabled, EDIT I seems to have limited emulate type: pc ...
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1answer
399 views

Can I setup a local webserver using ArchLinux and VirtualBox

I intend to create a local webserver using ArchLinux and VirtualBox for testing purposes. I just wonder if Arch Linux has what it takes to create a fully functional webserver?
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2answers
4k views

Getting config error for yum in CentOS

I'm very new to linux, and I am using CentOS in a VM for program testing. Everything seems to be fine, except for every few minutes I get this error: Error Type: <class 'yum.Errors.ConfigError'> ...
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5answers
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How to improve Windows perfomance when running inside KVM

I use Ubuntu 12.04 64-bit and KVM, my CPU is Core i5 3.3 GHz and I have 8 GB of DDR3 RAM. I run Windows 7 in KVM and it's extremely slow. My co-worker use Debian on the same PC configuration and can ...
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1answer
126 views

How to setup backup if the filesystem is read only

My remote server file system is read-only & its because my hard disk is broken .I want to take backup for taking any further action. Is it possible to setup a manual backup for the affected ...
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2answers
983 views

good Ubuntu/Debian distro for a development/coding VM?

I have a Windows laptop, but I like to use Linux as a development/coding environment. Currently I am currently running Ubuntu 12.04 as a guest OS with VirtualBox. Some of the issues with this setup ...
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2answers
343 views

Prevent hacking the grub.conf using a 'live rescue' from a live linux iso

It happened that I had set the grub password in grub.conf. But, using a live linux iso, I was able to delete the password from the grub.conf. Please read the steps for the same mentioned in this link: ...
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0answers
163 views

Unmanaged VPS bought today. Sendmail not functioning correctly

I purchased an unmanaged VPS today. I moved my website on over, and when I try to send an email. It returns a blank page. Not to mention I had to install PHP myself. Apache was there, for some reason, ...