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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VMWare ESXi 3.5 “Could not power on VM: No space left on device”

We have several VMWare ESXi boxes, and on some we get this message when trying to power on virtuals: "Could not power on VM: No space left on device Failed to power on VM" The Datastore is 67G, we ...
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2answers
765 views

SQL Server wont start on my 64-bit virtualization slice

I have installed SQL server 2008 express on a 64-bit virtual box and the service wont start. Looking at the event log I get: Could not create tempdb. You may not have enough disk space ...
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4answers
14k views

Why is TCP accept() performance so bad under Xen?

The rate at which my server can accept() new incoming TCP connections is really bad under Xen. The same test on bare metal hardware shows 3-5x speed ups. How come this is so bad under Xen? Can you ...
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2answers
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Difference between KVM and QEMU

I have been reading about KVM and Qemu for sometime. As of now I have a clear understanding of what they do. KVM supports hardware virtualization to provide near native performance to the Guest ...
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2answers
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Difference between Xen PV, Xen KVM and HVM?

I know that Xen is usually better than OpenVZ as the provider cannot oversell in Xen. However, what is the difference between Xen PV, Xen KVM and HVM (I was going through this provider's specs? Which ...
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Best Practices for virtualizing servers onto the SAN?

Alright, so I want to start leveraging my SAN a little more than I have been, and at the same time, take advantage of ESXi. Currently, I've got an array of Dell PowerEdge 1955 blades connected to a ...
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17answers
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Virtualization Pitfalls/Lessons Learned

What are some pitfalls or lessons learned after converting existing hardware to a virtualized environment? Is there anything you tried to virtualize but will never do again?
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6answers
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hardware recommendations for a DIY storage system based on ZFS [closed]

Looking to make use of old server lying idle as a proof-of-concept ...here are specs Dell PE 2900: Xeon 5110 - 2P, 12 GB RAM, 8x 300 GB 15K drives, Perc 5i+256 MB cache what additional h/w would be ...
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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 ...
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4answers
813 views

Are production servers running as virtual images a good idea?

What are the risks of running a production web server and database in on a virtual server? Currently we are thinking of using VM Ware server. It seems like a nice solution that will lead to easy ...
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2answers
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KVM on Illumos (OpenIndiana vs. SmartOS)

I'm considering virtualizing a number of guests onto a single server running a recent port of KVM to Illumos. It sounds like my two primary options will be OpenIndiana and SmartOS. The distribution ...
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3answers
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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 ...
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5answers
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How to extend a Linux PV partition online after virtual disk growth

VMware allows to extend the size of a virtual disk online - when the VM is running. The next expected steps for Linux system are: extend the partition: delete and create a larger one with fdisk ...
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2answers
6k 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 ...
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753 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 ...
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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 ...
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6answers
969 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 ...
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9answers
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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 ...
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5answers
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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? ...
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4answers
12k views

HP dl170 g6 and LO100 (iLO) - Can't boot from virtual media

I'm trying to make an HP DL170 G6 server boot via the "virtual media" feature. The system doesn't even try to boot from the virtual media, it seems unable to see it! Here's the test we've been doing: ...
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3answers
3k 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 ...
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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 ...
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2answers
3k 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 ...
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3answers
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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 ...
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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
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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 ...
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3answers
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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 ...
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3answers
5k 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 ...
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2answers
2k 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 ...
5
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9answers
15k 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?
4
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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 ...
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1answer
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What is the recommended method to prepare Red Hat/CentOS 7 templates?

If I need to deploy Red Hat 7 from template, I would like to take the recommended steps to make my "golden image" clean. It should boot to the first boot prompt and guide the user through the typical ...
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2answers
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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 ...
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1answer
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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 ...
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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 ...
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1answer
119 views

VMWare: Are long running snapshots really THAT bad?

This is ESXi 5.5. I know that the VMWare KB is very against long running snapshots, however I do not know of another way to do this. Let's say I have a base Linux system and want to spin up a unique ...
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2answers
2k 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 ...
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2answers
12k views

How to get a CLI for a virtual machine on XenServer?

I created a Debian Lenny virtual machine as described on the manual. How to control it? It has no IP since my LAN has DHCP disabled. If it only had a static IP and SSHD enabled I could just PuTTY it. ...
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6answers
5k views

Best Hosted VM Provider [closed]

We have some boxes at a reputable (expensive) hosting company. They don't offer a simple/flexible VM solution. All I want is the ability to create CentOS VMs (mainly) to host our (mostly) static ...
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10answers
7k 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 ...
11
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1answer
5k 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 ...
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5answers
548 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
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4answers
2k views

vCPU performance between 1 or 2 vCPU's

Within virtualisation (Predominantly VMware) is there a performance advantage using either 1 CPU with 4 cores or 2 CPU's with 2 cores? Let's assume the application running on a VM can use two CPU's.
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1answer
2k 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 ...
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7answers
827 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.
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1answer
633 views

Virtual vs. Named SQL Instances

What are the benefits to using virtual as opposed to running multiple instances of SQL on a box?
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2answers
405 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
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2answers
318 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 ...
4
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3answers
5k views

Convert directory to QEMU/KVM virtual disk image

I have a directory filled with data at /var/backups/disk1 that I want to convert into a virtual disk image which I'll then be able to boot using QEMU or KVM (the directory contains the file system for ...
4
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8answers
17k views

How should I convert a physical drive to a VHD for use with VirtualPC?

I have the hard disks from a PC that was happily running Windows Me until is it suffered an unknown hardware failure. The drives are intact, and can be mounted and read on other PCs. We have data ...