Need advice on VM Hosting

[eugenevdm]

Our company has been doing shared hosting for most of our existence but now we would like to move into virtual machine hosting (Windows and Linux). I would like some tips or suggestions on how to proceed. So far my limited research has shown that there are quite a lot of products to choose from, and so far I have narrowed it down to the following choices:

 

* Xen. Seems to be very popular, pity about the price and the recent price increases. At that price our return on investment will be very poor since I don't foresee us making money from it for the startup phase. Their cheaper version is limited to 4 VMs only as far as I know. I like the fact that there is an open source version but frankly we don't have the resources to learn and create everything from scratch. Unless you're saying it's really easy.

 

* VMWare. Seems to also be very popular and competing quite nicely with Xen. There is a nice free version but I still can't figure out the catch.

 

* KVM. I like the fact that it's bundled / integrated with Ubuntu, since we're adopting Ubuntu server as a strategy. It seems rather young though and the tools limited.

 

* Tonight for the first time I noticed HyperVM and the fact that WHMCS has a plug-in for it. What are your experiences using the plug-in and would you suggest this product? Does it actually use Xen? Can it do both Windows and Linux?

 

Also what's quite confusing is if we should go "bare metal" or "hypervisor".

 

A minor requirement would be to migrate some existing Windows and Linux machines to this new environment, I believe Xen has some commerial tools for this. This is luckily a minor requirement.

 

Ultimately whatever we choose has to play very nicely with WHMCS.

 

Any advice will be much appreciated.

[othellotech]

* Xen. Seems to be very popular, pity about the price and the recent price increases.

We use Xen Enterprise and whilst $3000 might seem a lot (and then $5000+ for the server)

when you can comfortably have 40 VM's running with almost complete separation it's well worth the money, they also turnaround patches for paying clients very quickly when needed.

 

* VMWare. Seems to also be very popular and competing quite nicely with Xen. There is a nice free version but I still can't figure out the catch.

The free version is cr@p, performance of the VM's is appaling, never tried the paid setup so cant comment on that

 

Virtuozzo is the other solution, for windows VM's I find it outperforms Xen, but has a similar cost, and the support from paralosers varies from helpful to utterly useless depending on who gets assigned the issue.

[SilverNodashi]

We use Xen included in the OS's - i.e no exterprise version, which is free. It works well, and does what it's supposed to.

 

To automate the VPS creation, we use HyperVM - which can be "controlled" by WHMCS to a point. But, when a client signs up, his VPS gets created by WHMCS automatically. Xen has the advantages of running Windows on top of Linux, and is much quicker than VMWare.

[netearth]

We use and and abuse XEN Enterprise, as Othello said, you cant go wrong with it

[uberhost]

* Xen. [snip] I like the fact that there is an open source version but frankly we don't have the resources to learn and create everything from scratch. Unless you're saying it's really easy.

 

It's really easy.

[SilverNodashi]

XEN = free & easy Very easy.

 

 

yum install xen xen-kernerl virtlib; reboot

 

then run virt-install to create the XEN instances.

 

 

OR, download & install HyperVM

[eugenevdm]

Awesome! Thanks!!!

[ur]

Performance-wise you will get a bit more out of a commercial XenServer, but if you are looking to host a small number of vpses or just getting your feet wet, there is nothing wrong with the free version. Performance of the latter has improved over the last several releases. (I would still join in recommending the commercial XenServer version for 'serious' hosting. Support is very good, plus I personally like the dashboard management utils).

 

That said, depending on what you want to host may lead you to choose one virtualization software over another. Xen, for instance has better internal timing of vpses over others which can be important for live telephony or video applications. Xen, however, is not yet supported by WHMCS and it's API (for the open-source distro) is not final, so it could be a long wait. VMWare server in our test proved to be relatively more resource hungry, but it does perform nicely with many picky applications, like a full blown asterisk with conferencing. Add to that, we had none of the typical kernel issues that arise from time to time with other virtualized environments.

 

For me, the question of going "bare metal" or "hypervisor" depends on your management and hosting needs, system spec and the virtualization server you will be employing.

 

With XenServer, the bare metal/embedded hypervisor actually supports "embedded" hardware. This can be quite a boon. You will also note that the Linux VMware server is also by default bare metal and ESXi is now free. Their other versions suggest a Windows OS host, although it should be possible to run with the ESXi. Another note with VMWare, ESXi will not let you manage many boxes easily (at least at the time we tried). It seems each VMWare box would need a host OS/ hypervisor, in addition to extra commercial management software (not sure how much).

 

The main thing for us, is making sure that the hardware required by the virtualized OS installations are properly supported. Cost is also a factor, and should be looked at closely. Don't expect to be able to sell $5 or $10 VPS with any commercial distro. It's just not feasible, that is if you won't be overselling.

 

You can easily use HyperVM to manage your Xen boxes. HyperVM is quite robust with powerful features and has a low cost of entry. WHMCS sets up the account, then your HyperVM will send out a welcome email which you can customize, WITH the vps IP.

[SilverNodashi]

Really? The commercial XEN is faster than the free one? I find it hard to believe, since XEN itself is a kernel, and the commecrial version is purely a set of tools on top of it to manage it.

 

I would suggest though, if you're going to offer virtual servers, Euegene, get onto a mailing list of which ever technology you choose, whether it be XEN, Virtuzzo, OpenVZ, KVM, or VMWare. If they have a developer's list, even better. The XEN list itself is full of good expertise and they are always helpful in any situation.

 

One thing I can tell you, in the OpenSource / Linux world, there is alway support And what ur said about the hardware is also true. Don't bother with cheap CPU's, get at least XEON, if you can, or otherwise a minumum of Intel 6800 and upwards - anything with VT support, if you want to offer full virtualization - i.e. windows / FreeBSD / Solaris / etc on top of Linux.

[ur]

Hardware:

Also compatible: Socket AM2/AMD-V support should also work very nicely.

Heads up for: Certain Intel Core 2 Quads that do not support VT as well as Core 2 Duo 8190(?).

See also compatibility guides/charts at xen.org and an extensive one at citrix.

 

Anyway.. you're correct, same kernel, but I didn't necessarily mean faster. The commercial xenserver (ie enterprise) has the ability to tweak resource allocation and create resource pools along with other tools...making larger installs definitely more performant/efficient/easier to manage etc.

 

On an interesting side note it did appear to us that overall latency seemed lower with xenserver (DomU > Dom0, and back), and similarly with disk I/O. But that may purely be a quirk.

[RapidCityHosting]

(Yes i know this thread is old)

 

From my research, it seems that HyperVM/OpenVZ is actually the guinea pig for Virtuozzo(Now Parallels). The features that go into it, normally make their way into it.

 

Xen while nice, is actually slowly being shadowed by OpenVZ. From benchmark tests, OpenVZ is actually performing better than Xen. However, I have not compared the features of each.

 

I did notice that in WHMCS, the OpenVZ plugin, gives the option to select either HyperVM or xen.

 

The OpenVZ w/ HyperVM is limited to 5 servers, then its $0.50 or so a server after that. Not too big of a deal considering how much we really make from vps's.

[SilverNodashi]

OpenVZ (and Virtuzzo) is not full virtualization. You cannot compare it with XEN / VmWare / QEMU / KVM / etc. It's not the same thing. While you can run virtual private servers on OpenVZ / Virtuzzo, you're limited to using the same kernel, and hence the same linux. With very few exceptions you'll get different distro's working on OpenVZ, but not much.

 

For full Virtualization, (i.e. two completely different OS's on top of each other), you need to look @ XEN / KVM / QEMU / etc. OpenVZ will never "shadow" XEN.

 

See the following threads:

 

http://en.wikipedia.org/wiki/Operating_system-level_virtualization

http://en.wikipedia.org/wiki/Partial_virtualization

http://en.wikipedia.org/wiki/Full_virtualization