Virtualization is a group of software technologies that allow abstraction between layers of a system. This allows separation between the logical layers of the system, providing isolation, flexibility, and/or the ability to run more than one at a time. This differs from most traditional systems where ...

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23
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4answers
678 views

Will virtualizing a server mean another OS layer to patch and update, more work and greater risk?

I've done a search and have not found anything addressing issues regarding patching and system updates. I've got guidelines that say servers need to have necessary patches. If I have a VM host then ...
17
votes
3answers
3k views

Virtual vs Physical Servers

I'm after a second opinion; and apologies if this has already been answered (point me in the right direction). Different factions within a project I'm on are engaged in a holy war between virtual vs ...
10
votes
4answers
15k views

KVM: Which CPU features make VMs run better?

We are using Ubuntu 12.04 with the following parameters: Dell R910 Kernel 3.2.0-25-generic #40-Ubuntu SMP x86_64 x86_64 x86_64 GNU/Linux kvm 1:84+dfsg-0ubuntu16+1.0+noroms+0ubuntu13 qemu-kvm ...
10
votes
3answers
5k views

How much overhead does x86/x64 virtualization have?

How much overhead does x86/x64 virtualization (I'll probably be using VirtualBox, possbly VMWare, definitely not paravirtualization) have for each of the following operations a Win64 host and Linux64 ...
9
votes
6answers
950 views

Accurately trending random I/O performance for capacity planning

Where I work we have a numerous "big iron" servers which are used used for hosting many virtual machines using a Xen Hypervisor. These are typically configured with 32GB RAM, Dual Quad core processes ...
4
votes
2answers
5k views

Backup of KVM guests when using qcow2 disk files

I got a Ubuntu (hardy) system used for virtualization using KVM. Each guest got it's own qcow2 file used as disk. Guests are running Ubuntu (hardy). What would a good backup strategy be for such a ...
5
votes
2answers
5k views

How do I change the size of a VHD?

I have a fixed size virtual hard drive that is running out of space. What's a good way to go about increasing the size? This VHD is created from Microsoft Virtual PC and/or Microsoft Virtual Server.
14
votes
9answers
13k views

Is it possible/advisable to run VMware Server ESX/ESXi on a laptop?

The idea of having a small footprint hypervisor as the primary OS on a laptop or desktop where every "real" OS is a guest appeals to me. Now I realize this software is more typically used on blades ...
5
votes
5answers
2k views

Is it realistic to run Windows Server 2008 with 1GB of RAM?

I am just about to "invest" in a cheap Windows 2008 VPS ($30 per month!) which comes with 1GB. Before I do that I thought I would ask if its realistic to expect a usable server with only 1GB of RAM? ...
4
votes
3answers
2k views

Is KVM stable enough for production use in 2011?

We are planning to virtualize the existing infrastructure by an open source virtualization solution. KVM and Xen are on the final list. Big cloud players are still using Xen, and we found that KVM is ...
4
votes
2answers
2k views

How to make SQL Server 2008 redundant?

At the moment I'd like to combine my departmental SQL Server into one big SQL Server 2008 instances spread across two servers (for redundancy reason). How/what is the best way to approach this ? is ...
4
votes
2answers
2k views

Running an Active Directory Primary Domain Controller as a virtual machine?

Should the Active Directory PDC always be a physical machine or would it be okay to run it in a VM? What are the implications/trade offs/gotchas? As a corollary to this, what about running a physical ...
2
votes
3answers
2k views

How to run OS X (Leopard or Tiger) in Windows?

Is there a way to run Mac OS X (Leopard or Tiger) in Windows on a virtual machine? I have 2 GB of RAM and a 2 GHz processor. My processor is an 32-bit AMD, but I don't think this will matter because ...
0
votes
6answers
6k views

How we build private cloud computing in my organization

I'm young admin in some organization, I would like to know how we prepare private cloud computing. Like what cloud computing consist of ? Regards Pond
8
votes
2answers
1k views

Adding new virtual disks to a RHEL host in ESX “live”

I'm sure I've just missed which tutorial/manual page covers this, but how do you add get the guest OS to recognize that you've added new drives to it without a reboot? I have a RHEL5 guest running on ...
6
votes
3answers
3k views

Is the Amazon EC2 instance id unique forever?

We're using amazon EC2 and we want to keep track of instaces. Is the Amazon EC2 instance-id unique forever? i.e. If a VM has an instance id of i-12345678 is there a guarantee that when that instance ...
6
votes
9answers
2k views

What software is available to simulate a LAN?

I've been using VMWare to simulate a simple LAN (a DC and several workstations hosted on a single machine). The LAN will be used as a test environment for software that is currently in development. ...
5
votes
2answers
3k views

use LXC under heavier virtualization (Xen, KVM,Hyper-V,VMVare)

Is it possible to use LXC under heavier virtualization (Xen DomU,KVM,Hyper-V,VMVare) ? I would like to use it as security (isolation) tool, the ability to limit resource consumption is not priority ...
4
votes
5answers
3k views

vmware server end of life, where to go now?

We have some virtual machines on vmware server 2.x running on 64 bit hardware and quite happy with it. As vmware server will no longer be offered we are thinking to migrate to ESXi, which seems is ...
4
votes
10answers
17k views

Which Linux distribution runs smoothly in Sun's VirtualBox?

Apparently some distributions do not run smoothly in VirtualBox. For example I installed Fedora 11 and I couldn't configure monitor's screen resolution to more than 800x600. What distribution run ...
3
votes
1answer
3k views

KVM network bridge with public static IP for both host and guests

I have a Ubuntu 10.04 server with 2 public static addresses. There is a KVM guest (also Ubuntu) installed and running. What i want is to give the guest an IP of the host, so that both machines have ...
3
votes
3answers
6k views

How does the LeftHand SAN perform in a Production environment?

I previously asked this ServerFault question: Does anyone have experience with lefthands VSA SAN The general consensus looks like it does not perform well enough for a production SQL server even at ...
2
votes
1answer
10k views

How to change a VM from split across multiple .vmdk files to a single one or two?

I have a VM with 3 partitions. One main one, one for swap space, one for storage. However, there are dozens of .vmdk files. Some of those .vmdk files are very large (over 1 GB), but the majority ...
2
votes
2answers
1k views

Mount LVM within a disk image

I have a disk image that I made with KVM. The partition layout inside the disk image is as follows. [root@centreon01 2tb-external]# fdisk -lu vdisk1.img Device Boot Start End ...
2
votes
8answers
8k views

How to find out if a Solaris machine is virtualized or not?

I have a set of machines and want to know how to find out if a given machine is virtualized or not. Any commands?
10
votes
10answers
4k views

Are there any good reasons for disabling hardware-assisted virtualization?

We've had a number of servers from Dell recently, all of which have had hardware-assisted virtualization disabled in the BIOS. As far as I know hardware-assisted virtualization is a good thing - so ...
8
votes
0answers
3k views

Read/write access for passthrough (9p) filesystems with libvirt/qemu?

I have recently started experimenting with the support for passthrough filesystems in recent versions of KVM/QEMU/libvirt. Making the filesystems available for read access has "just worked", but I'm ...
7
votes
3answers
2k views

What to change after cloning a Linux server?

Let's say I'm cloning a virtual machine containing a Linux server. What would you advice to change in the clone? I know - it's kind of vague and depends on what services ware installed on linux but ...
6
votes
5answers
505 views

Virtualizing Microsoft SQL Database server

My company is looking to virtualize our Microsoft SQL server. I read on another question that databases on VM's suffer from a IO bottleneck which is not very good for us. But I was wondering if ...
5
votes
1answer
1k views

Does kern.hz still have any relevance in FreeBSD if “dynamic tick mode” is enabled?

I'm running a FreeBSD 9.0 setup as a virtual machine in a KVM setup. In previous versions of FreeBSD it was common to force the kern.hz setting to a lower value so that the virtual machine does not ...
5
votes
3answers
3k views

Is there danger to virtualizing a router?

I had read on a few forums about pfSense that said it was dangerous to virtualize pfSense. The reason that was stated was an attacker could use pfsense as a spring board for an attack on the ...
5
votes
7answers
578 views

Make a copy running VM-ware Virtual Machines

I want to backup my virtual machines while they are running, is it possible to do this without buying more VM-Ware products? They are running on CentOS 5.2.
5
votes
1answer
581 views

Virtual vs. Named SQL Instances

What are the benefits to using virtual as opposed to running multiple instances of SQL on a box?
4
votes
1answer
237 views

How do I make all Xen guests use their host clock value?

I've set up Xen server under Linux with several guests running, and all was well. After some time I've noticed the clock on the server drifted away, so I installed 'ntpd', and the clock was back to ...
4
votes
2answers
274 views

Migrate VM from Virtual to Physical Server

I’m after viewpoints on my situation from my fellow sysadmins. I think I have thought of the points, but want someone else’s opinion. I have an ESXi5 Cluster consisting of 5 Physical machines: 4 in ...
3
votes
2answers
840 views

When NOT to use virtualisation?

When virtualisation was new, we tried to virtualise everything, but then we noticed use cases where the our virtual machines were much slower than a bare metal. For us, we use the following rules ...
3
votes
2answers
497 views

Dedicated ip's for xen guests

I'm having a hell of an issue getting networking working in Xen on Ubuntu Server. Our server has a few public IPs (/29) that are all added through eth0 aliases. E.g. eth0 - main ip eth0:0 - first ...
3
votes
2answers
11k views

Can't ping host from vmware guest using bridged networking

Host is Windows 7 Guest is Ubuntu 11.04 Network adapter is wireless I can ping other computers on the network but not the host. No firewall are involved. Sniffing the traffic with wireshark it ...
3
votes
3answers
836 views

KVM “live migration finished” detection

I'm using KVM (through libvirt actually) for a research project. We're live-migrating a virtual machine between different subnets, so after the migration the IP address and routing tables have to be ...
3
votes
2answers
371 views

Should our web-app go Cloud or multiple VPS?

Let's say we have a web-app and there's an automated/under-the-hood process which updates the DB. At the moment, they all ran in the same server. We'd like to separate the batch-process from the ...
2
votes
2answers
262 views

How can I automatically create/control VMs using vsphere?

Is it possible to automatically create virtual machines using vSphere / ESXi? How would I go about doing that? I have a script to automatically create + install windows on a VM using VirtualBox. It ...
2
votes
4answers
378 views

How can i verify from a command prompt, if a linux host is real or virtual

How would know at command line that the Linux host i logged in to is real machine, with linux installed, or is a virtual machine Thanks, -Kamal.
2
votes
5answers
1k views

Decent hardware (< $1.500) for Hyper-V dev/test machine

I'm looking to build a decent < 1.500$ dedicated Hyper-V solution for development and testing purposes. The parts list I was thinking of is: Intel Core I7 920 $288.99 (fastest affordable desktop ...
1
vote
0answers
320 views

Ghost “vlan 0” tags added to ethernet frames in CentOS guest under OpenStack

I'm trying to debug an issue involving a KVM virtual machine instance where the instance doesn't respond to network requests when the source is on another physical machine, which is on the same subnet ...
1
vote
1answer
3k views

Managing XEN through virt-manager on ubuntu 12.04

I have been trying to make xen work on a remote machine with no GUI.Installed XEN hypervisor on the machine and booted in that kernel.Try to create VM using virt-manager. I tried accessing ...
1
vote
3answers
720 views

Blade Enclosure, Multiple Blade Servers, Whats the closest approximation to a DMZ?

I appreciate that to get a proper DMZ, one should have a physical separation between the DMZ servers and the LAN servers, with a firewall server in between. But, in a network consisting of a single ...
1
vote
4answers
890 views

OpenVZ Host is the source IP address rather than actual web surfers?

I am experiencing something a little bit odd. I'm running OpenZV on a CentOS 5 server. It appears that on containers the source IP address that say Apache webserver sees a request from is the OpenVZ ...
1
vote
3answers
925 views

Can a virtual PC find out the identity of its host?

There's a Microsoft Virtual PC instance on my network that runs build scripts and reports problems by sending me an e-mail. I don't what machine it's running on! I can access the machine by Remote ...
1
vote
1answer
319 views

VPS solution to match cloud scalabilty and reliability

Having this architecture in mind: server 1: webserver - floating/surges of CPU load and BW consumption server 2: dbserver - floating I/O from webserver and steady/heavy I/O from batch-process server ...
1
vote
1answer
1k views

DRBD experimentation and virtualization

This was one of those thoughts that were tickling the back of my mind. I'm working on a home testbed of a high-availability cluster consisting of just computers, not a SAN or NAS for storage, just ...