nixCraft

john_sm · #1 (**permalink**) 12-31-2007, 07:47 PM

Hey Folks - We need your help. We were hoping, we could gain from your experience with implementing server virtualization. When should we be using Red Hat Virtualization, Citrix Virtualization, Xen Virtualization, Microsoft Virtualization, Oracle Virtualization and VMWare. I will be very interested in learning from your first hand experince. I will also like to know, under what situations is one virtualization prefered over the other. - Thanks for your help

rockdalinux · #2 (**permalink**) 01-01-2008, 05:20 PM

Welcome to fourm!

Do you have any specific usage in mind? Virtualization itself is a broad term. Virtualization applied to applications, computers, storage and many other concepts inclding iPods. Common application of virtualization.
#1 Disaster recovery
#2 Education, Testing and training
#3 Server consolidation (many physical servers into fewer server

#4 Hardware Level virtualization using Intel and AMD boxes / T1 hypervisor
#5 Hosting multiple web sites (VPS) / Root server etc

Personally, I love to use Vmware because of its support, ease of use and disaster recovery features. My personal home box runs many instance of Linux distro and Windows using XEN.

Hope this helps!

PS: Citrix Virtualization and Xen are same things (Citrix brought Xensource company). Also, Oracle VM = Redhat VM = XEN VM are same thing sponsored and supported by same different commercial entities

simoncrosby · #3 (**permalink**) 01-02-2008, 07:52 AM

Quote:

Originally Posted by john_sm

Hey Folks - We need your help. We were hoping, we could gain from your experience with implementing server virtualization. When should we be using Red Hat Virtualization, Citrix Virtualization, Xen Virtualization, Microsoft Virtualization, Oracle Virtualization and VMWare. I will be very interested in learning from your first hand experince. I will also like to know, under what situations is one virtualization prefered over the other. - Thanks for your help

I'm admittedly biased (CTO XenSource), but here's my take. If you want to virtualize Windows, the XenSource/Citrix product is the only one worth looking at. The rest all think that just having some PV I/O drivers does the job, but that's far from enough. If you just want to do Linux on Linux, and you're an expert at Linux config and hackery, then use whatever comes with your distro, assuming you don't want any scalable management tools.

Oracle VM has a more up to date version of Xen than RHEL5, and they have at least patched their kernel ahead of where Red Hat is, but their management tool is rudimentary to say the least. Red Hat's is no better, SUSE's is a little better but written in Eclipse, and very slow. Ours, by the way, is entirely Windows based (.net MMC client) so if you are utterly Linux based then you won't want to use it.

Suggest you download our entirely free product 4 VMs linux or Windows, XenServer Express, at www.citrixxenserver.com; if that's the use case you want, then either that's enough or you'l want to purchase upgrades. Otherwise try FC7 or OpenSUSE or Debian (by the way we ship a Debian VM template with the product), and see what flavor suits you. Also, XenServer requires VT. If you're using pre VT gear, then you're (a) Linux only and (b) prob want to go for one of the Linux versions. But then your management tool options are pretty limited.

Simon

SimoneS · #4 (**permalink**) 01-05-2008, 09:11 PM

Hi john_sm, i'm quite new in virtualization, but actually I'm using vmware server (it's not open, but free to download and use) with windows 2003 server. Over it, i virtualize a cluster of two web servers (debian 4.0r1 with apache+php) to try high availability with heartbeat and two database servers (debian 4.0r1 with Oracle 10g XE). Performances are good and the virtual machines creation is fast because I've created a single virtual machine (a kind of template), then I've cloned it several times. In this way I don't waste my time in building new machines from zero. Also, if I made mistakes with a virtual machine, I can destroy and replace it with a new one in just few minutes.
About XEN, I know it's a software for para-virtualization that consist in a software layer that besides immediately over the hw of your real machines. It runs only on linux and can virtualize only linux-like systems.
Virtual box is an open source solution for virtualization, but it's used frequently by desktop users, for example to try new linux distributions without installing them (I don't know if virtualbox it's used seriously also in server and production environment

.
Finaly, there's virtual pc by microsoft, but I've never used it.
So, there are many solutions for virtualization, but depending of your needs.

Simone

cosminnci · #5 (**permalink**) 08-20-2008, 03:41 PM

Hello,

I would like to knkow what software to use for VPS, we have a server with centos5.2 I read that centos has VPS included, is it on the same instalation as centos or needs aditional packages?

regards,
Cosmin

rockdalinux · #6 (**permalink**) 08-20-2008, 03:48 PM

Yes, it has XEN included. Typing following will install the same:

Code:

yum install xen virt-manager kernel-xen
chkconfig xend on
reboot

To install new os, enter

Code:

virt-manager &

Virtualization Guide

cosminnci · #7 (**permalink**) 08-20-2008, 05:21 PM

Would like to use it for webhosting VPS, what else does it require?
for normal server we install cpanel and it installs everything.
ex for email will it use the already installed linux mail client or needs to be installed one for that VPS?
any how to`s on configuring VPS would be great.

thanks

rockdalinux · #8 (**permalink**) 08-20-2008, 10:26 PM

For webhosting VPS you need at least 4GB RAM, RAID 10 Disk storage, Dual Core Dual CPU server. CentoS or RHEL Linux server os.

Then you install VPS server software such as XEN or Virtuozzo vps software. Virtuozzo is quite popular. This is called host.

Once installed you need to install Guest OS such as Debian / Ubuntu per node.

End user need Plesk or cPanel inside VPS node to manage their daily tasks.

Parallels Virtuozzo Containers

cosminnci · #9 (**permalink**) 08-21-2008, 01:05 AM

Server config is 16Gb Ram, hdd 146G SAS 15000Rpm Raid 1 cpu quad Xeon 2,5GHz
you were saying raid 10? why is that?
How many 256 Mb VM could this server run?

So on this server install centos5.2 with XEN or Virtuozzo (does this need to install over centos?)
then install centos (d`ont plan to use Unbutu or Debian) and cpanel for each virtual machine?
and each VM needs private ip adress.
I noticed there are virtual machine monitors, are these included by defaut ?

nixcraft · #10 (**permalink**) 08-21-2008, 01:30 AM

Xen acts and looks like a dedicated server. With XEN you can have custom kernel, firewall and other stuff.

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