Changes

Who am I? This article originally written by [http://www.perkel.com Marc Perkel] - a new VPS user - expressing my overview of OpenVZ from my perspective as a new user talking to other new users about my experience in learning this new environment. I am not an OpenVZ expert and I want to write this while I'm still new to OpenVZ so I can express my view from a new user's perspective. If you are just reading about VPS for the first time I am not that far ahead of you. This article is an attempt by me to give back a little to those who created this free software and give you new people anoverview an overview of the big picture as I learn this myself.

Like many of you when I first heard of the idea of VPS I pictured it is some small lame server that is sold to 12 year olds trying to start hosting companies on the cheap. It had never quite caught my attention until I decided I needed a remote name server and all I needed was enough of a server to run bind, but didn't want to by buy a dedicated box just to do that. So I got a VPS based on Virtuozzo for $80/year and it worked great.

In the process however I started understanding the VPS concept and it became apparent that this is more that than just a tool to create little servers. The way I see it VPS can replace dedicated servers in many situations in a data center and do a better job than dedicated. You can actually give the customer more horsepower and better hosting than selling them a small dedicated box. (Of course big customers will still need their own server.)

I don't own a data center business myself but I have a friend who does and I colo several servers there. He has several racks of some old Celeron boxes with 512 mgs of ram and one or two 80 gig drives depending of on if the customer has any concept of backups, which most of them don't. I'm looking at the racks of Celerons and P4s thinking that each rack could be consolidated into a single modern server and that the customers would actually have a better server than the one they are on now. And the cost saving is tremendous.

Most small dedicated servers are a waste of resources. People buy bigger servers than they need and the excess capacity is wasted. These servers take both space an and power which is expensive in a data center and you have hardware costs assiciated associated with each server that you have to recoup. People often don't do any backups so after several years the hard drive fails and they lose everything. And it's your fault for not backing them up in the first place.

Imagine a rack of 16 Celeron boxes with 80 gig drives being replaced by a Dual Core Athlox X2 with 8 gigs of ram and 4 500gb SATA 2 drives running in a raid 10 configuration. (Writing this in Feb of 2007 for future historians who will read this an and laugh at the old days when computers had just gigabytes.) The above server would cost about $2000 to build and only take 2U of space and use far less power than the 16 machines that are being replaced.

Not Note also that many of these servers have idle time where the processor is doing nothing and they have lots of extra hard drive spave space that isn't being used. By consolidating these systems the free resources are combined allowing you to run many more logical servers that each have more resources than the individual servers.

Setup couldn't be easier as compared to building a dedicated server. All you have to do is type a few command commands and the new virtual server is ready to go. You can have the customer running while you are still on the phone taking the order. A dedicated box requires setup, installation, and often has to be scheduled. This involves cost and time. VPS is read ready instantly and easily. Any distro you want with all the latest updates installed. When a customer places an order they want it now. With VPS you can deliver it now.

Tired of allocating 4 IP addresses just to give the customer 1 usable? Or giving them 8 so they have 5 usable and them most of them only use one? How inefficient is that? With OpenVZ you can allocate IP addresses individually so that if a customer only needs one IP then they get only 1 IP. But if they need 9 IP addresses you can give them exactly 9 of them. They can call you up and say I need one more IP and you can give it to them in seconds. On a dedicated server if you gave them a /29 vlan and they are using all 5 IPs and they need another one - that is a huge hassle.

On dedicated servers you have to install a big hard drive that is mostly wasted. If the customer wants backups then it's two hard drives. In OpenVZ you just allocate space in the raid array based on what the customer actually needs and they only use the space that they use rather than what's allocated. The "allocation" is really just a software limit and that is a line in a text file that you can instantly change the moment the customer needs more space. On a dedicatd box if the customer need needs a bigger drive then it's a trip to the data center with a new drive and a few hours time to copy everything over and replacing the drive, not to mention the down time.

Memory upgrades are as easy as hard drive upgrades. Juch Just one command that than the user has more ram. But what if the server is full and you don't have any more ram? No problem. Just copy the user's VE (virtual environment) over to another physical server with rsync and start them up there. In only a few minutes you've migrated them to a new box and they are up and running.

Let's say that a server fries. With VPS and good backups you have more options. You can copy the backup of the VPS onto abother another server and restore it as of the last (nightly) backup. (I'm a backup freak - but it pays.) That gets the customers up instantly if they need that while a tech can go down there and fox the server with less pressure. This give you more options when bad things happen.

Since you are managing the host system you can create IP filters and port blocking policies that help keep users from exploiting you or keep hackers from exploiting your users. Instead of a separate box that is all theirs you have them in a more managed shell allowing you to keep the inexperienced out of trouble. This provides them with a service that watched it watched more closely allowing them to do their own thing, but keeping you closer by to keep them out of trouble.

I believe that VPS represents the future of computing. The space, power, and cost savings are too great to ignore. I see data centers that are massive clusters running tens of thousands of logical servers that transparently migrate around the physical resources and are up 100% of the time. Customers no longer will have to deal with issues of backups they the way they have to now , and it will simplify the hosting process. I think that every data center should be looking into virtualization technology now with the idea that you are going to be doing this and it's time to at least start thinking about it and exploring it with an eye towards the future.