VMWare vs Xen

[KrishMurali]

We plan to introduce virtualization on our co. So researching for that. And wenarrowed in on xen and vmware. Need a few clarifications from you.

1. Do we have any document detailing the diff bet vmware & xen

2. will xen support all vmware images and vice versa so that we can depoly both?

3. which product of vmware suits us? (we typically have 2 GB RAM,40 GB HDD virtual images) we use boh windwos and lnux

4. we also need support for 64 bit (very few in number..but need them) will which product of vmwre can do that?(EM64 machines)64 bit for lnux and wndows

5. Which is expensive?

[esiebert7625]

ESX would probably be what you want. Esx is going to be more expensive then Xen but it is a much more featured and mature product then Xen.

ESX has 64-bit VM support as long as you get 64-bit server hardware. Here's some links you can read through.

http://www.vmware.com/community/thread.jspa?messageID=569978&tstart=0

http://www.vmware.com/community/thread.jspa?threadID=98295&tstart=0

A Performance Comparison of Hypervisors - http://www.vmware.com/pdf/hypervisor_performance.pdf

VMware Versions compared - http://www.petri.co.il/virtual_vmware_versions_compared.htm

Choosing between VMware Server and ESX Server - http://www.virtualization.info/2006/12/choosing-between-vmware-server-and-esx.html

Vmware Infrastructure Architecture Overview - http://www.vmware.com/pdf/vi_architecture_wp.pdf

[spolly]

The two biggest issues that I see with Xen are:

1) the only way to backup a Xen VM is with inside the guest agents. VMware ESX has multiple options for image level backups which are a nice benefit of virtualization.

2) I believe Xen still does not support fiber channel, so you're limited in your storage options.

The images are not interchangeable, but there are products available that can convert one to the other.

[MR-T]

Watch this space very closely.

I think Xen already have a product which is worth a look, but with the backing Citrix could provide, next year could become an interesting market with Microsoft releasing their product.

http://www.theregister.co.uk/2007/08/14/xensource_goes_citrix/

[Texiwill]

Hello,

Depending on the Xen product you purchase you may be severely limited in what you can do, the same can be said for ESX however.

If you do not know Linux then using Xen is not for you.

Features:

virtual switch capability..... Xen has bridges, and NAT, and there is a way to setup something like a virtual switch but it is fairly involved and complex.

Guest Creation.... VIC provides a very nice secure remote client for Windows. There is no VIC for Linux. Xen has something similar but it will only run on Linux systems and can be displayed back to Windows machines using VNCViewer or run an X server. When running on a Linux system that is not the Xen host, the communication is unsecured.

HVM (Hardware Virtual Machine)... ESX does this for you. Xen you need to choose that or paravirtualized. For windows VMs in Xen you must use HVM.

Access to local SCSI devices... ESX has a very nice graphical way to do this. Xen requires server configuration files to be properly edited by hand.

Remote Storage... ESX has NFS, SAN, iSCSI.... Xen has NFS, SAN, iSCSI, CIFS in effect whatever Dom-O can support you can place a VM image upon.

Raw Disk Maps... ESX has generic support for RDMs.... Xen has this as well, but has limited support for remote LUNs.

VM Creation... By hand is supported on each. Xen's configuration file is much shorter.

Remote Console... ESX uses the VIC/Web... Xen uses VNC.

virtual switch firewalls... ESX does not have anything... Xen uses iptables and rules can be used to protect VMs. Remember virtual switches per say do not exist in Xen.

There is quite a bit to compare between the two.... Both work, both have limitations....

Best regards,

Edward

[bwold]

XEN will mature rapidly. IBM and HP do a lot of business in system virtualization yet they compete with EMC in storage. By selling VMWare, they are strengthening the competition. I would be very surprised if they do not pour a lot of resources into Xen testing and developement. Also, I spoke with an engineer at HP that supported that opinion.

[MR-T]

I totally agree with you.

There will be healthy competition very soon.

It can only be good for the consumer.

[mreferre]

Well this might be the case (even though I must say upfront I don't sit at the tables where it is decided what it is good or what it is bad for my company).

Another thing to take into account is that as VMware continue to push themselves into the "management tools" arena they are going to compete with more and more organizations.

On the other hand who you partner with is a function of what users want. It would be easy to NOT partner with company xyz because maybe/perhaps it might compete with your on this front etc etc etc ..... the problem is what happens if every customer wants products from company xyz.

You don't want to go to war with water-guns ... don't you ?

Massimo.

[mreferre]

It can only be good for the consumer.

This is the most important thought in this thread. Very true.

Massimo.

[kimono]

It can only be good for the consumer.

This is the most important thought in this thread.

Very true.

I hear ya there. Going to be a very interesting couple of months.

[Texiwill]

Hello,

I think what will win out in the short term is the 'Management Appliance' for the Virtualization box. So far Xen is mostly by hand or graphical just for VMs and not for server configuration. Unless you know Linux Xen is not for the faint of heart.

ESX has a very good management tool, but it does not have a Linux version which for Linux only shops may push them towards Xen. Virtual Iron has a nice UI and its underlying technology is Xen.

Xen is picking up steam but until it has a good remote management tool, people will view it as archaic. BTW, I do know several are in the works.

Best regards,

Edward

[bwold]

I agree. However, offering other options to the customer while developing a competing product is what is happening. I believe that this product is by far the best of breed "right now". I do not know what will happen in 2 yrs. There is too much money in system virtualization for one company to dominate without serious competition. MS product will continue to improve and companies will choose to deploy those products over VMWare because MS is MS and not because it performs better. We've seen that happen in the past.

wonder how many companies are developing management apps that will bring multiple system virtualization (VMware,XEN, MS) products under one umbrella, similar to what is happening in the storage industry.

[bowulf]

What settles it for me is support. I might not need to call VMware or engage professional services much anymore, but initially I had questions. Having the reassurance of support (other than relying on e-mail) would be a necessity before I started putting production, mission critical things in an ever-changing environment.