Comments on: Virtualization Recommendations

Question: Virtualization Recommendations

afx114 — Fri, 16 Feb 2007 10:51:01 -0800

LAMPFilter: Which VPS solution (Virtuozzo, VMware, freeVPS, etc) is recommended for a small web-hosting company?

I run a small web-hosting company who in the past has always used dedicated servers for larger clients. But with today's modern servers sitting mostly idle, even for traffic heavy sites, we're looking into a virtualization solution to combine multiple dedicated servers into one VPS'd powerhouse machine.

I've done plenty of research online about the various options, but I am looking for anecdotal evidence and experience of real life users out there. How realistic and how easy is it to get a VPS setup going? Any happy or horror stories are appreciated.

(Note: We run strictly LAMP-style servers)

By: onedarkride

onedarkride — Fri, 16 Feb 2007 12:47:57 -0800

Xen is the best thing ever.

Easy things:
New host configuration. Host info is in an external config file, you can basically copy generic images to make new hosts, boot them with the modified config file, and kapow, you're done. Want to move it to a new machine? SCP, take the config file with you, done.

Then again, most of this stuff works roughly the same with everything. The only reason I pimp on xen is because i used it before VT was around, and the performance impact was WAY less than anything else.

It's not that hard to set up, the instructions walk you through it very well, and jesus, does it ever work well.

By: SpecialK

SpecialK — Fri, 16 Feb 2007 13:00:55 -0800

Most of the people who end up being users on VPSes hate Xen. Although I have to say, my Xen server is faster than my Virtuozzo server.

Only thing you have to watch is your memory consumption and limits. I know that in default configuration, Apache can completely eat a RAM-starved virtual server and the VS's kernel will start killing processes off to save itself from being overwritten in RAM. (Which is actually a feature ... it's why Linux doesn't BSOD.) If it picks your master apache or mysql process for termination, you'll lose that ability on your server.

So yeah, watch the configuration and use min 256, but better 384+ MB of RAM ... and make sure that Apache is set to recycle it's processes fairly often so that they don't leak memory.

By: afx114

afx114 — Fri, 16 Feb 2007 13:21:53 -0800

Thanks for the advice. One question I forgot to ask - is it worth waiting for the built in kernel virtualization (KVM) that is now making its way into the kernel? Will it make all the 3rd party solutions obsolete? Or am I confusing the two?

By: dorian

dorian — Fri, 16 Feb 2007 15:46:52 -0800

I am a big fan of xen; it is pretty bad-ass. paravirtualization makes much more sense to me than os-level virtualization. if you have the right cpu (i.e. w/ hardware virtualization support: pacifica or vanderpool) you can even run un-modified os (e.g. windows) in it with minimal penalty.

that said, openvz is a lot easier to set up and run in my experience.

virtuozzo is basically openvz with some better features and a shiny windows management console, integration with plesk/hspc/swsoft_other.

if you're just planning to do generic lamp then openvz will be pretty straightforward for you. e.g. if you know how to use yum then it will be pretty clear how to use vzyum.

By: dorian

dorian — Fri, 16 Feb 2007 15:55:39 -0800

(and yes stuff from xen and openvz is making its way into the mainline linux kernels but I wouldn't hold my breath)

By: rsanheim

rsanheim — Fri, 16 Feb 2007 19:23:03 -0800

SpecialK: I'm a Xen user on 3 different VMs, and I've been happy with each one. The only problems I've had have been due to me doing dumb things (ie trying to run too much stuff on a slice w/ not much ram.)