It appears many people find it hard to understand what VPS is and how it works, so I just thought I'd make a small effort to explain a littlebit.

What does VPS mean?
Virtual Private Server

What is such a Virtual Server?
Basically VPS is all about running multiple Virtual Servers within one physical server.

What does Private refer to?
Each VPS gets its own portion of resources, which are usually guaranteed to be available to that particular VPS. For instance, the host server may have 8GB of ram, and 256mb (for instance) could be guaranteed to be available to a VPS. That would mean that regardless of what other VPS's on the same server use, that amount of RAM will be available to the VPS.

Also very important: each VPS runs completely independent of eachother. Each VPS has its own filesystem so a VPS can't see any of the data of another VPS. Also each VPS has it's own server load, can run its own Operating System, can be rebooted individually, and so on. Basically by the end user it can be treated as a dedicated server.

So does a VPS also have its own kernel?
Usually not, but it depends on the technology that the host uses.

Are VPS's truly 100% isolated from eachother, so no matter what happens they can not cause trouble to eachother?
Under normal circumstances, yes. However in extreme scenarios, VPS's can trouble eachother. For instance if the host server has a 100mbit uplink, and one VPS gets a 100mbit DDoS attack, then it makes sense that all other VPS's on the same server are also affected by it. It's up to the host to ensure maximum reliability by monitoring everything closely.

I mentioned VPS's on the same host server can each run a different Operating System. So could one VPS on the server run Windows, and another one Linux?
No, that's not possible. It is however possible to run different Linux distributions on a Linux VPS server. For instance one VPS could be running Red Hat Enterprise, and another one could be running Debian.

Is it possible to run anything on a VPS that would run on a dedicated server?
As long as it doesn't require kernel modifications, yes. (note: some technologies do support kernel modifications - that's not something I specialize in though)


For everyone who still has trouble understanding what VPS is, I thought of a nice example:

You could compare VPS technology to a block of apartments. The block has one roof, but under that roof there are multiple apartments. Each apartment has its own kitchen, living room, etc, so it can operate individually. Everyone goes in and out through the same door of the building though (VPS: traffic all goes through one network port). And I'm sure you can think of every other similarity.

You could compare VPS technology to a block of apartments. The block has one roof, but under that roof there are multiple apartments. Each apartment has its own kitchen, living room, etc, so it can operate individually. Everyone goes in and out through the same door of the building though (VPS: traffic all goes through one network port). And I'm sure you can think of every other similarity.
Nice example:) How about gas, electricity and water:)

That could be compared to the resources like CPU, RAM and bandwidth - they come in through the same pipes and are then divided among apartments/vps's. There are probably a ton of other similarities to think of :)

Think of it as an appartment Block Each VPS in the Dedicated server is a Home, 1 Roof Many Homes :D

I'm definitely loving the example. Hahaha! Good tutorial mate.

ahaha! It couldnt be better!, nice tutorial.

nice insight, very useful for people who dont know this shaded sector of hosting

Very helpful indeed, I realise I am a latecomer to this thread but, I am a new member on this forum as well.

Before ever buying a VPS research who you are buying it from. Way too much risk otherwise. That is my two cents. Also, look for someone who puts customers first as in the game of hosting that is not the case with many. Being able to support your customers is all that really matters as that is where people fail.

-Jay

Great work man.
Simply awesome example

It appears many people find it hard to understand what VPS is and how it works, so I just thought I'd make a small effort to explain a littlebit.

What does VPS mean?
Virtual Private Server

What is such a Virtual Server?
Basically VPS is all about running multiple Virtual Servers within one physical server.

What does Private refer to?
Each VPS gets its own portion of resources, which are usually guaranteed to be available to that particular VPS. For instance, the host server may have 8GB of ram, and 256mb (for instance) could be guaranteed to be available to a VPS. That would mean that regardless of what other VPS's on the same server use, that amount of RAM will be available to the VPS.

Also very important: each VPS runs completely independent of eachother. Each VPS has its own filesystem so a VPS can't see any of the data of another VPS. Also each VPS has it's own server load, can run its own Operating System, can be rebooted individually, and so on. Basically by the end user it can be treated as a dedicated server.

So does a VPS also have its own kernel?
Usually not, but it depends on the technology that the host uses.

Are VPS's truly 100% isolated from eachother, so no matter what happens they can not cause trouble to eachother?
Under normal circumstances, yes. However in extreme scenarios, VPS's can trouble eachother. For instance if the host server has a 100mbit uplink, and one VPS gets a 100mbit DDoS attack, then it makes sense that all other VPS's on the same server are also affected by it. It's up to the host to ensure maximum reliability by monitoring everything closely.

I mentioned VPS's on the same host server can each run a different Operating System. So could one VPS on the server run Windows, and another one Linux?
No, that's not possible. It is however possible to run different Linux distributions on a Linux VPS server. For instance one VPS could be running Red Hat Enterprise, and another one could be running Debian.

Is it possible to run anything on a VPS that would run on a dedicated server?
As long as it doesn't require kernel modifications, yes. (note: some technologies do support kernel modifications - that's not something I specialize in though)


For everyone who still has trouble understanding what VPS is, I thought of a nice example:

You could compare VPS technology to a block of apartments. The block has one roof, but under that roof there are multiple apartments. Each apartment has its own kitchen, living room, etc, so it can operate individually. Everyone goes in and out through the same door of the building though (VPS: traffic all goes through one network port). And I'm sure you can think of every other similarity.

Very nicely explained man.

theres a program i think people who do vps should install, i cannot remember the name of it but it makes certain computers have a certain amount of connection to the internet on a router, the program is installed on the computer and is then passworded by the admin to stop people using up all the bandwidth, also if you're really cheaky you can have it on one computer (aka the server) and limit what uses how much connection without people being able to access it. That would a) cut down on monitoring b) make sure people get the connection they are guarenteed

Is it possible to allocate and guarantee a certain amount of bandwidth to each VPS user on the same physical server?

Also, if I were to get a dedicated server, how could I configure the server to use VPS technology rather than cPanel?

Is VPS better than cPanel?

Thanks mate. I found this tutorial useful.

Is it possible to allocate and guarantee a certain amount of bandwidth to each VPS user on the same physical server?

Technically that is possible but it's not a very common practice to do so, simply because usually it's not needed if you have a 100mbit uplink.

Also, if I were to get a dedicated server, how could I configure the server to use VPS technology rather than cPanel?

Is VPS better than cPanel?

I think you didn't really get it :)

VPS technology and cPanel are two completely different things. A VPS is a virtual server, cPanel is a control panel which controls a server. VPS technology basically splits one physical server into multiple virtual servers. cPanel only controls a server by automating many tasks of the webserver, mailserver, etc. It is also possible to run cPanel on a VPS (exactly the way it runs on a physical server).

You could compare VPS technology to a block of apartments. The block has one roof, but under that roof there are multiple apartments. Each apartment has its own kitchen, living room, etc, so it can operate individually. Everyone goes in and out through the same door of the building though (VPS: traffic all goes through one network port). And I'm sure you can think of every other similarity.

When I explain what VPS technology is, I like to say that it's "shared dedicated hosting". It includes the same features of a dedicated server (root access, hords of space and bandwidth, etc), but multiple customers are physically housed on the same server.

now to find a vps thats honest! :)

now to find a vps thats honest! :)

There are lots of those. I'm a customer of servint.net - nice people.

ive been with myvpshost for about a week now no complaints and are very customer oriented, will wait a month to post my real praises just in case though :)

Test their sales email reply times as well support. First impressions show true colors.

-Jay

within minutes and very friendly, even let me chose to leave a few default applications uninstalled to save time and resources.

Can someone explain the managed and unmanged vps?

Anything to take note from shared hosting to a vps? What can we expect?
Thank you.

leotan,

Umanaged means you as the VPS owner have to update the OS and applications as security fixes are released, etc. Saying your not Managed doesn't mean this isn't done upon request it simply isn't part of the marketing angle.

When going from shared to VPS you now have your own mini server with dedicated resources like Disk Space, Memory, and CPU. You can sleep well knowing you aren't on a shared server sitting beside 100+ others who can at anytime kill the server if they don't know what their doing. VPS's cuts back the risk and allows you to not worry about such things.

-Jay

Hi

do you know how we can setup a VPS on our dedicated server ?

Yeah, I'd be interested in learning that too...how do you setup VPS on a dedicated server?

Test their sales email reply times as well support. First impressions show true colors.

-Jay

In my opinion sales reply times say nothing it all. Support does, of course.

Hi

do you know how we can setup a VPS on our dedicated server ?

For starters you need virtualization software, such as Virtuozzo, Xen, UML, VMware, FreeVPS, OpenVZ, or any other that I may have missed. Quite simply, if you don't know anything and don't have a huge amount of time to learn the technology, then don't even bother.

If you need just one VPS the easiest thing to do is to simply get one from an established reputable provider. If you want to start offering VPS to your (potential) clients yourself while you don't know anything about the technology (and don't have enough money to hire people to hanlde this for you) then it might be an idea to resell the VPS's of a reputable provider. If done right, your end client will not be able to see that you are reselling the products of an other company.

The above is the easiest way to get started and is pretty much risk-free, because if you would run your own servers you'll have to go through a lot before you are able to provide a reliable product to your clients.

I mentioned VPS's on the same host server can each run a different Operating System. So could one VPS on the server run Windows, and another one Linux?
No, that's not possible. It is however possible to run different Linux distributions on a Linux VPS server. For instance one VPS could be running Red Hat Enterprise, and another one could be running Debian.


You guys at Dehe have been running Virtuozzo too much. Face the reality and understand you need to upgrade your knowledge, you know NOTHING about Xen.

http://www.xensource.com

IT IS possible to run different operating system on the same physical Hardware. It has been one year that it's possible to run NetBSD, FreeBSD and Linux with Xen 2.0, wa have some customer doing it.

Since Xen 3.0 is out, it's also possible to run Windows and Linux on the same physical machine if you have a VT processor. Xen 3.0.2 seems quite stable now (older 3.0 was not), and VT enabled processors are getting cheaper everyday (it's now possible to get them for less than 250 USD).

Thomas

You guys at Dehe have been running Virtuozzo too much. Face the reality and understand you need to upgrade your knowledge, you know NOTHING about Xen.

Maybe you should face the reality and look at the timestamp on these posts. At the time of writing Xen 3 was not released yet.

Please accept my public appologies about what I said. I feel sorry. You are right, I should have seen the timestamp.

Thomas

How hard is it to manage a VPS..?

I've been with a shared-hosting since starting my first website couple of years ago, now..that I publish couple of busy MySQL driven websites, I need to concentrate more on the site contents and marketing rather than managing a server that I have lots to learn to..

So what sort of maintanance do we need to do it on our own to get our VPS runs smoothly from times to times..?

Mainly, you have to upgrade your server regarding security. If you know about the security updates for windows, it's about the same...

For the rest of, if you have a control panel to manage your site, it should be as easy as using your shared account, but with more freedom (you can install what you want on the server).

Thomas

That's quite helpful, even though I know it all it still is nice bit of information to back myself up. :)

Good job.

I am just trying to understand this. No plans to buy.

I thought all vps were only managed servers because it is one physical box.

Please add to this tutorial by correcting me if I am wrong.

Colbyt

Even if there is one physical computer, there are many operating systems running at the same time. Each of them has it's own hard drive, memory, and IP address(es). It's just like if you were running totaly independant servers. So all of the operating systems on the server needs to be managed by somebody (and upgrades have to be made on all of them).

Thomas

It appears many people find it hard to understand what VPS is and how it works, so I just thought I'd make a small effort to explain a littlebit.


What indepence is there for MySQL database as far as space and simultaneous connections and such ?

(I am thinking like for running poweful MySQL bases applications such as vBulletin forum and phpAdsNew banner rotation)

Each VPS has its own processes, just like on a dedicated server. Most providers limit the number of processes you can run on your VPS, but usually this is not the limiting factor (RAM or CPU is, usually). You also get a certain number of available sockets, which also varies from provider to provider. Each VPS comes with a certain amount of harddisk space, which is used to store everything, just like a dedicated server, ranging from system libraries (although those are often shared by the whole node) to public_html files to MySQL databases.

So to answer your question in one sentence; in the aspects you are looking at a VPS, it'll be completely independent from all VPS's on the same server.

If you are looking into hosting a forum with a lot (hundreds) of simultaneous connections, I'd recommend to ask the host for their exact limitations on sockets, processes, and things like that, so you can determine whether you won't hit the limits. I personally would never limit a VPS based on sockets for instance, as I find that somewhat unethical, we just limit factors such as RAM, and when a customer hits a limit such as sockets we usually just increase that limit. Now you might ask why we have a limit at all - that's for the sake of system safety, so that the system won't spin out of control in the event of an attack for instance.

I hope that answers your question, it's always a bit complicated to explain something like this if you haven't worked with the technology before.

Very nice tutorial, very extensive good read!

Thanks for the tutorial Apoc.


I mentioned VPS's on the same host server can each run a different Operating System. So could one VPS on the server run Windows, and another one Linux?
No, that's not possible. It is however possible to run different Linux distributions on a Linux VPS server. For instance one VPS could be running Red Hat Enterprise, and another one could be running Debian.
Some Virtualisation software have this restriction but Vmware ESX server will happily run any operating systems side by side on the same server, not just linux.

How about the MIN RAM factor, how sure can you be that your provider is not overselling the RAM, i am no telling this because i have problems, but this is really a question that i have in mind.

From what ive been reading this board , some people say that only Xen virtualization software can assure you that your provider is not overselling, but what about virtuozzo :)

Thank you

Some Virtualisation software have this restriction but Vmware ESX server will happily run any operating systems side by side on the same server, not just linux.

Yeah I'm aware of that, at the time I posted this tutorial that wasn't possible yet though (to the best of my knowledge).

How about the MIN RAM factor, how sure can you be that your provider is not overselling the RAM, i am no telling this because i have problems, but this is really a question that i have in mind.

From what ive been reading this board , some people say that only Xen virtualization software can assure you that your provider is not overselling, but what about virtuozzo :)

Thank you

There is no way to be sure about that, that's where the host's reputation comes in. A host which oversells its guaranteed ram will (more) frequently get complaints/negative reviews about bad performance/failures than a host that doesn't.

Needless to say, guaranteed ram should never be oversold (if the guarantee is oversold, there is no guarantee), but since it's technically possible to do so, certain companies will try to exploit that. Reputable companies know better than that :)

Hey André, nice explanations.

What about CPU-power? Is it freezing the others when 1 VPS-user is taking 100% of it, or does the base system somehow regulates this into maximums and in a way guarantees each VPS minimum space for CPU load?

Also; if there's that one 100 mbit NIC (usually there are two for redundancy), and a user is crossing VPS-es with huge traffic, so it goes from one VPS to the other on the same actual base server, what does the routing actually look like? Will it be rooted externally (first hop outside of server), or is the NIC sharing all of the IP-addresses at the same time in a way it will not take up the 100 mbit and route via the base OS's localhost?

And if one VPS *is* using 100 mbit (it's not that hard to do these days), is any other traffic over it still guaranteed for the other VPS-es? Is there a minimum In/Out value set for that?

I'm very fond of Ivan Barrera's bw_mod which does such things on the application level of Apache: http://ivn.cl/apache/ so I'm guessing Openvz (and the likes) also somehow guarantee bandwidth for each. I have used (and still use) bw_mod on some very busy webservers (with limited speed), where it really manages to secure bandwidth for smaller files, which is basically the most important thing on the internet, plus it assures each request with a minimum of for example 2 kB/s. They should have built that option IN httpd or lighttpd.

I can answer you about Xen, Andre might talk about VZ.

With Xen, if a VPS takes 100% of the CPU while others are doing nothing, this VPS will have 100% of the CPU. If let's say you have 2 VPS taking 100% of the CPU, they will each get 50% of the total available.

For bandwidth, it deals with the way Linux does it's network queuing. On the normal way, it's rather random. But if you set inteligent queuing with a scheduler (let's say CBQ which is the most simple one), then the packets will be prioritized and each VPS will have what it needs (well shared).

For both CPU and Network, it's possible to set priorities and ratio. For network, it's also possible to set maximum values (while it's only possible to do so with lastest scheduler for CPU, if I'm not mistaking).

Note that it's not very smart to give a VPS a maximum of let's say 50% of the CPU, because if it takes 4 seconds to do a calculation, then it will take 8, and finaly the overal CPU time taken will be the same. It's better to have all VPS go as fast as possible, and only do scheduling when there is not enough CPU for all.

The most problem with VPS is in fact I/O. I know people are working on having a better I/O scheduler for Xen, and it's in fact much much needed as this is where you wait the most. Especialy, it's very bad when a VPS does a lot of swapping. We are currently working on trying to make a real time graphic like we did for CPU and Network, so we would be able to know who's taking the most I/O time. But unfortunatly, it's possible to have the information only on the lastest version of Xen (otherwise it falls back to the /proc per partitions stats, if the kernel module is in).

I hope this will help you to understand a bit more what's beyond the scene.

Thomas

I can't speak for all hosts here when it comes to CPU power, but I can explain how we (and most other Virtuozzo based hosts) do it:

CPU regulation is based on CPU units, which are relative. For instance, we have a 3 VPS plans, the starter plan, business plan, and enterprise plan. The starter plan has 1000 CPU units, the business plan has 1500 CPU units and the enterprise plan has 2000 CPU units. Now if 2 Starter VPS's both try to use 100% CPU, it would be a 1000:1000 ratio, as both VPS's have 1000 CPU units. As such, each VPS will receive 50% of the total CPU capacity.

Another example: 1 starter VPS and 1 enterprise VPS each try to use 100% CPU. The ratio is 1000:2000, so the starter VPS will receive 33% of the total CPU capacity, and the enterprise VPS 67%.

Needless to say, the more VPS's that are active at the same time, the more complicated the math becomes, but that's something Virtuozzo takes care of. If 10 starter VPS's are trying to use 100% CPU, each of them will get 10% of the total capacity.

It speaks for itself that the host will have to make sure to not place too many VPS's per server.

As for the routing; I also can't speak for other hosts there, but we usually create a VLAN for a certain amount of servers, put a few /24's on those VLANs and then assign those IPs to the individual VPS's. Virtuozzo makes sure that customers cannot hijack eachothers' IPs within the VLAN.

Our servers are connected with 2x gigabit NIC's to 2 (redundant) switches, and each VPS is capable of using a max of 100mbit each. So even if a VPS uses up all of the 100mbit, there's still 900mbit left.

Limiting bandwidth on the application level is probably a good idea for shared hosting, I agree. I think the reason they haven't built this in Apache by default is that it's meant to be a generic daemon. It's not specifically intended for shared hosting, it can also be used for many other projects in which bandwidth limiting would be bogus.

I would like to question the real advantages of VPS?

I understand that it offers a cheaper solution between a Reseller Account and a Dedicated server. This is one obvious benefit, providing a stepping stone. The whole privacy/security aspect is good, but is VPS an effecient approach? I mean ultimately VPS plans are used by individuals / businesses to have root access at a lower cost - which is usually to allow them to sell Reseller Accounts to their own clients on a budget. But this can be done with other software, such as WHMreseller for cPanel, which works out to also be a much cheaper option.

While VPS gives excellent control, it also introduces much more complexity to the user, they need to be fully fledged server administrators. Also having so many Operating systems running simultaneously, duplicates tasks over and over again, eating up much more of the servers CPU & Memory, leaving less for the useful tasks (Apache, Mysql, etc). VPS software is also quite expensive for the Host Provider as it requires not only the VPS software itself but the purchasing on multiple Control Panel software licenses (such as VPS Cpanel licenses).

Overall while I can see VPS has a lot to offer I also think its kinda messy with stacks of setting up required, has duplicated processes running (wastage), is generally expensive for the host and is probably more prone to ddos attacks. Sorry if this sounds negative, don't get me wrong its a brilliant idea, I guess I'm just weighing up the cost <-> to benefit ratio. The VPS software available (stuff thats any good) is too expensive in my opinion.

I would like to question the real advantages of VPS?

I understand that it offers a cheaper solution between a Reseller Account and a Dedicated server. This is one obvious benefit, providing a stepping stone. The whole privacy/security aspect is good, but is VPS an effecient approach?

Yes it is, very efficient. Each of the customer having access to separate partitions (LVM is often used), it's impossible to access files of another customer.

I mean ultimately VPS plans are used by individuals / businesses to have root access at a lower cost - which is usually to allow them to sell Reseller Accounts to their own clients on a budget. But this can be done with other software, such as WHMreseller for cPanel, which works out to also be a much cheaper option.

You are considering only very specific options to use cPanel to do email and web hosting. Many uses VPSes to do differents things. I have in mind Asterisk VoIP server, IRC, Ruby On Rail, Python, backup MX & NS, and many other things that you cannot do with a cPanel account.

While VPS gives excellent control, it also introduces much more complexity to the user, they need to be fully fledged server administrators.

If using a control panel, it's not that hard... but true it adds complexity for the final customer. Consider also that some customer switched from dedicated servers to VPS because they only need the root access and don't want to pay too much.

Also having so many Operating systems running simultaneously, duplicates tasks over and over again, eating up much more of the servers CPU & Memory, leaving less for the useful tasks (Apache, Mysql, etc).

With modern virtualizations systems, it's as fast to run in a VPS than on the real hardware. In other words, the virtualization system don't add any overhead. Why do you think it uses more CPU then? For sure, more memory, but that's it. Having an operating system running takes virtualy no CPU if it does nothing. So only Apache, MySQL, etc. (like you said) will take some CPU.

VPS software is also quite expensive for the Host Provider as it requires not only the VPS software itself but the purchasing on multiple Control Panel software licenses (such as VPS Cpanel licenses).

True if using Virtuozzo/Plesk. Not true if using Xen which is open source and some open source control panel for apache and the mail system. In that case there is no cost for software.

Overall while I can see VPS has a lot to offer I also think its kinda messy with stacks of setting up required, has duplicated processes running (wastage), is generally expensive for the host and is probably more prone to ddos attacks. Sorry if this sounds negative, don't get me wrong its a brilliant idea, I guess I'm just weighing up the cost <-> to benefit ratio. The VPS software available (stuff thats any good) is too expensive in my opinion.

Xen is totaly free once again, seems you have only virtuozzo in mind. There is no waste in running multiple instance of Apache, in fact if doing so, many files will get cached on the memory instead of being loaded from the hard drive, so it will go faster if well managed. True a VPS server is quite expensive to buy at first (a lot of hard drive and memory), but at the end it's more profitable for a host in the long therms. The ratio cost <-> benefit is very good.

Thomas

I would like to question the real advantages of VPS?

I understand that it offers a cheaper solution between a Reseller Account and a Dedicated server. This is one obvious benefit, providing a stepping stone. The whole privacy/security aspect is good, but is VPS an effecient approach? I mean ultimately VPS plans are used by individuals / businesses to have root access at a lower cost - which is usually to allow them to sell Reseller Accounts to their own clients on a budget. But this can be done with other software, such as WHMreseller for cPanel, which works out to also be a much cheaper option.

While VPS gives excellent control, it also introduces much more complexity to the user, they need to be fully fledged server administrators. Also having so many Operating systems running simultaneously, duplicates tasks over and over again, eating up much more of the servers CPU & Memory, leaving less for the useful tasks (Apache, Mysql, etc). VPS software is also quite expensive for the Host Provider as it requires not only the VPS software itself but the purchasing on multiple Control Panel software licenses (such as VPS Cpanel licenses).

Overall while I can see VPS has a lot to offer I also think its kinda messy with stacks of setting up required, has duplicated processes running (wastage), is generally expensive for the host and is probably more prone to ddos attacks. Sorry if this sounds negative, don't get me wrong its a brilliant idea, I guess I'm just weighing up the cost <-> to benefit ratio. The VPS software available (stuff thats any good) is too expensive in my opinion.


Firstly, it's not necessary to be a fully fledged server administrator if you go with a host that offers a managed solution.

There are countless benefits of a VPS solution:

- With a quality host, your VPS will be hosted on an enterprise class server, with high-end RAID arrays, redundant power supplies, a true server motherboard, and so on. If you would get a dedicated server of the same price, you wouldn't get any of the reliability that you get with such a VPS.

- As for the comparison with a reseller account; a reseller account shares all of its resources with all other reseller accounts on the same server. A VPS gets guaranteed resources, so even if an other VPS on the same server overloads, your VPS wouldn't be affected by that.

- There are no Operating Systems running simultaniously, as all VPS's share the same kernel. Also OS libraries and processes are shared, at the host-layer of the system. This is done very efficiently by all popular virtualization software available. There aren't any duplicate processes running really, except for idle Apache daemons maybe.

- A VPS is not more prone to DDoS attacks than a shared (reseller) hosting environment, actually it's the other way around. Since each VPS gets guaranteed resources, only the VPS that's being attacked will really be affected by it (of course it's a little different if the attack is huge - but that can also take down an entire network). On a shared hosting environment you don't get such isolation between accounts. If a reseller account gets attacked, all other reseller accounts on that server will be affected by it. Of course, a dedicated server offers even more isolation, but you can't get the high-end (reliability) servers specs that a VPS offers, in a dedicated server, at the same price of a VPS.

So to sum it up, the main advantage is that you get an enterprise-grade hosting environment, which is completely isolated from other customers, at just a fraction of the costs of a complete (high-end) dedicated server.

- There are no Operating Systems running simultaniously, as all VPS's share the same kernel. Also OS libraries and processes are shared, at the host-layer of the system. This is done very efficiently by all popular virtualization software available. There aren't any duplicate processes running really, except for idle Apache daemons maybe.

Not true with Xen. Xen runs a separate kernel instance for each systems. You can even run a NetBSD kernel or even windows even with a Linux dom0.

Thomas

nice reply apoc, that should be added to the firsth post.

You made me notice a nice point of view about shared , vps and dedicated.

Really nice reply Apoc.

I am not buying. I am just collecting information. Bandwidth and disk space being equal, how much vps does a person need to get dedicated server quality from a vps account? What specs?

Not true with Xen. Xen runs a separate kernel instance for each systems. You can even run a NetBSD kernel or even windows even with a Linux dom0.

Thomas

Yeah I have to add that basically all my replies in this entire thread are mainly based on Virtuozzo/openvz as that's where my core experience lies. Feel free to correct me if any of the information I provided is inaccurate for Xen/UML/any other virtualiztion software :)

On a sidenote; I am aware that Xen runs a seperate kernel for each VPS. In my opinion the main disadvantage is that that adds more of a performance overhead (less resources are being shared), but the advantage is that the kernel can be (individually) modified for each VPS. From my experience over 99% of all people don't need that though, but it's useful for those who do.

Edit: and I forgot to add: another very nice advantage is the ability of being able to run a very wide range of Operating Systems, while with Virtuozzo you're bound to either Linux (Centos/fedora/debian/etc) or Windows.

There are many advantages to both Virtuozzo and Xen, both are simply wonderful technologies. For our business model Virtuozzo works best, but I can think of countless other business models for which Xen is more suitable. I think it would go a bit too far to really go into the specific advantages/disadvantages - trying to keep this thread a bit simple as it's mainly intended for those whom are new to virtualization technologies :)

Really nice reply Apoc.

I am not buying. I am just collecting information. Bandwidth and disk space being equal, how much vps does a person need to get dedicated server quality from a vps account? What specs?

That really depends on what kind of server you are referring to, and what kind of services you will run on the VPS.

With almost every host, a VPS will be faster than an Intel celeron, for instance. I think that the performance of an average VPS nowadays can be compared with the performance of a (single) P4 3.0ghz, but this varies.

It also depends on what kind of services you run. For instance gameservers really aren't suitable for a VPS environment, as they consistently need to use a lot (e.g. all) CPU. Basically a VPS is suitable for any purpose, as long as it doesn't consistently need to use just about all CPU that the host machine offers, and as long as it doesn't need more than about 1GB RAM (consistently). For more than 1GB ram, a dedicated server will usually be more cost effective.

On a sidenote; I am aware that Xen runs a seperate kernel for each VPS. In my opinion the main disadvantage is that that adds more of a performance overhead (less resources are being shared).

One thing you didn't think about as well is that all user kernel can be interrupted by the hypervisor. Meaning that a kernel call can be preempted. This is a very powerfull advantage. Also, each kernel will use his own file cache, and files get cached better. Of course, this uses a lot more memory...

I agree it's a bit silly to FIGHT about Xen / VZ, but I'm happy to understand both products advantage, and this kind of discution helps.

Thomas

I agree, but I would suggest opening a seperate thread for discussing the advantages of VZ vs Xen, as this thread really is intended for those whom are new to VPS technology as a whole.

Firstly, it's not necessary to be a fully fledged server administrator if you go with a host that offers a managed solution.

If your reason for getting a VPS is to save money (so you don't have to pay for a dedicated server) then how would you save money if you were to pay for your VPS to be managed too? Managing a VPS is the same as managing a dedicated server, whoever manages it needs to be a fully fledged server administrator and I don't think most VPS clients want to pay for it to be managed too.


- With a quality host, your VPS will be hosted on an enterprise class server, with high-end RAID arrays, redundant power supplies, a true server motherboard, and so on. If you would get a dedicated server of the same price, you wouldn't get any of the reliability that you get with such a VPS.


I don't fully agree with this because you're not getting the whole server, you're getting a slice, and a Bigger server is not always better, its how big your individual slice is that counts. If the Host fully utilises the server (fully populates it) then you're only guaranteed the CPU and Memory resources of the VPS plan, not the entire server. With the Hosting Industry being so competitive these days I don't know of any Hosts that don't want to fully populate (utilize) their servers.

- As for the comparison with a reseller account; a reseller account shares all of its resources with all other reseller accounts on the same server. A VPS gets guaranteed resources, so even if an other VPS on the same server overloads, your VPS wouldn't be affected by that.

True for now, but not for long, WHMreseller is being developed to delegate resources and guarantee minimums to reseller accounts, just like VPS but with only the single Operating System.

- There are no Operating Systems running simultaniously, as all VPS's share the same kernel. Also OS libraries and processes are shared, at the host-layer of the system. This is done very efficiently by all popular virtualization software available. There aren't any duplicate processes running really, except for idle Apache daemons maybe.

Ok but think of all the crons, logs processing, multiple installations of the same software (Apache, Mysql, Exim, etc)

- A VPS is not more prone to DDoS attacks than a shared (reseller) hosting environment, actually it's the other way around. Since each VPS gets guaranteed resources, only the VPS that's being attacked will really be affected by it (of course it's a little different if the attack is huge - but that can also take down an entire network). On a shared hosting environment you don't get such isolation between accounts. If a reseller account gets attacked, all other reseller accounts on that server will be affected by it. Of course, a dedicated server offers even more isolation, but you can't get the high-end (reliability) servers specs that a VPS offers, in a dedicated server, at the same price of a VPS.

True regarding CPU & MEM isolation, but WHMreseller will soon also provide this. The very thing you are saying is an advantage with VPS is also its weakness. Large, High-end servers that you say are typically used for VPS plans will ultimately be more highly populated servers. With all that CPU power and muscle such servers will have many more users per server. The more users (websites) on a server the more chance of a DDos attack for that server.

So to sum it up, the main advantage is that you get an enterprise-grade hosting environment, which is completely isolated from other customers, at just a fraction of the costs of a complete (high-end) dedicated server.

Don't get me wrong - yes VPS is an excellent option and great technology, but I just wanted to point out that there are some things to think about. The main reason I am arguing against you is because I am appauled at how expensive VPS can be from a Hosting Provider perspective. Virtuozzo is the best VPS, and it costs an arm and a leg too. Then on top of that you have to purchase individual cPanel (or Plesk etc) licenses for EACH user (each VPS). Software such as WHMreseller, cuts through all these costs and only requires a single cpanel license that ALL users can take advantage of.

If your reason for getting a VPS is to save money (so you don't have to pay for a dedicated server) then how would you save money if you were to pay for your VPS to be managed too? Managing a VPS is the same as managing a dedicated server, whoever manages it needs to be a fully fledged server administrator and I don't think most VPS clients want to pay for it to be managed too.

I don't think you get this correctly. Many VPS service providers (like us) include the management with their prices. For instance all of our products on our website include full management without additional fees. If you look at the prices, you'll easily be able to conclude that you won't be able to get a fully managed dedicated server at that price.



I don't fully agree with this because you're not getting the whole server, you're getting a slice, and a Bigger server is not always better, its how big your individual slice is that counts. If the Host fully utilises the server (fully populates it) then you're only guaranteed the CPU and Memory resources of the VPS plan, not the entire server. With the Hosting Industry being so competitive these days I don't know of any Hosts that don't want to fully populate (utilize) their servers.

That's not the point. The point is that you get enterprise grade hardware. On a low-end dedicated server you get a cheap motherboard, no raid, CPUs which originally aren't intended for server use (e.g. aren't meant to be online 24/7), etc. On a VPS you get enterprise grade hardware. Sure, you only get a slice of a RAID array, but that slice of that raid array is a whole lot more reliable than a single harddrive in a budget dedicated server.


True for now, but not for long, WHMreseller is being developed to delegate resources and guarantee minimums to reseller accounts, just like VPS but with only the single Operating System.

That would never offer the level of isolation that VPS does.


Ok but think of all the crons, logs processing, multiple installations of the same software (Apache, Mysql, Exim, etc)

That doesn't waste any resources really. Whether 10.000 emails are being processed by a single daemon or by 10 daemons will not make a difference. Only when a daemon is completely idle it will waste some resources, I agree, but why would someone get a VPS if it's going to be idle? Most VPS's aren't, so they simply don't waste resources.



True regarding CPU & MEM isolation, but WHMreseller will soon also provide this. The very thing you are saying is an advantage with VPS is also its weakness. Large, High-end servers that you say are typically used for VPS plans will ultimately be more highly populated servers. With all that CPU power and muscle such servers will have many more users per server. The more users (websites) on a server the more chance of a DDos attack for that server.

The ratio will still be the same. If a server is more populated, it'll concequently also be a bigger server, which can take more. Furthermore if a VPS gets attacked it'll only affect that VPS, not the whole server.



Don't get me wrong - yes VPS is an excellent option and great technology, but I just wanted to point out that there are some things to think about. The main reason I am arguing against you is because I am appauled at how expensive VPS can be from a Hosting Provider perspective. Virtuozzo is the best VPS, and it costs an arm and a leg too. Then on top of that you have to purchase individual cPanel (or Plesk etc) licenses for EACH user (each VPS). Software such as WHMreseller, cuts through all these costs and only requires a single cpanel license that ALL users can take advantage of.

Virtuozzo isn't that expensive if you calculate the costs per VPS. Sure, there are cheaper options like the software you mentioned, but those do not offer true isolation between customers, while VPS technology does.

That's not the point. The point is that you get enterprise grade hardware. On a low-end dedicated server you get a cheap motherboard, no raid, CPUs which originally aren't intended for server use (e.g. aren't meant to be online 24/7), etc. On a VPS you get enterprise grade hardware. Sure, you only get a slice of a RAID array, but that slice of that raid array is a whole lot more reliable than a single harddrive in a budget dedicated server.


VPS does not guarantee a fantastic server with Raid and all the rest of it. It isn't "VPS" that means you get good hardware, its the Host Provider themselves. You can get reseller accounts on servers with excellent "high-end" hardware too you know, just shop around. I am comparing VPS with reseller accounts, not dedicated servers.


That would never offer the level of isolation that VPS does.


You don't know for sure what level of isolation WHMreseller will offer in the near future so you can't really make a statement like that yet, wait and see first.


The ratio will still be the same. If a server is more populated, it'll concequently also be a bigger server, which can take more. Furthermore if a VPS gets attacked it'll only affect that VPS, not the whole server.


I agree that VPS adds protection because it isolates each root users CPU, MEM etc but can you agree that on a bigger server with more websites (and clients) there is more chance of a ddos attack for that server? For example if you had a server with 1 website as compared to a server with 1000 websites there is more chance the server with 1000 websites will be attacked than the one with one website. If the attack was large enough then the single network card on the server would mean its possible the attack could affect all VPS accounts still since they all use the same single network card.

Anyway I will conclude by saying - VPS is great technology. I have nothing against the technology, I only really have something against the pricing of virtuozzo.

but you can run a windows and a nix vps on the same server :/

VPS does not guarantee a fantastic server with Raid and all the rest of it. It isn't "VPS" that means you get good hardware, its the Host Provider themselves. You can get reseller accounts on servers with excellent "high-end" hardware too you know, just shop around. I am comparing VPS with reseller accounts, not dedicated servers.

<snip>

I agree that VPS adds protection because it isolates each root users CPU, MEM etc but can you agree that on a bigger server with more websites (and clients) there is more chance of a ddos attack for that server? For example if you had a server with 1 website as compared to a server with 1000 websites there is more chance the server with 1000 websites will be attacked than the one with one website. If the attack was large enough then the single network card on the server would mean its possible the attack could affect all VPS accounts still since they all use the same single network card.
So you're saying that a VPS server is not necessarily bigger than a reseller but because it's bigger it's more likely to be ddosed?! :stickout:

You don't know for sure what level of isolation WHMreseller will offer in the near future so you can't really make a statement like that yet, wait and see first.The advantages you're claiming depend on it still being a virtual-hosting (shared) solution. If so, it offers less isolation.

As a user of both VPS and reseller this is how I see the differences. Both can be on different levels of hardware and can be loaded differently, so if we want to compare the technologies we should assume a similar hardware platform and a similar total number of sites hosted. So based on that:

VPS offers more security - if one VPS is hacked with a root exploit the others will still be safe.
VPS offers more isolation - if one VPS is overloaded there will be less effect on the others (although there can still be problems with disk access particularly)
VPS offers more freedom - root access and the ability to install different applications, or configure them differently.
Reseller allows more "burst" resources, but the risk of account suspension for overuse.
VPS offers low risk of account suspension but limited burst, so may bog down when busy.
Reseller should be more efficient (because of virtualization overhead and duplication between VPS).
Reseller server management is easier (because VPS allows multiple configurations) so generally should be better / cheaper.
VPS resource management is easier - because of cpu / memory limits.
Reseller server monitoring is easier (because of the need to monitor multiple VPS and because there are more users who will notice if a reseller server misbehaves) so generally should be better / cheaper.
Reseller licensing costs probably cheaper than VPS (for main node and individual VPS control panels)
Reseller users carry no responsibility for server management and updates. VPS users, even on fully-managed accounts, may need to request updates.


Overall a well-managed reseller account should be a little cheaper than a similar VPS (all other things being equal) and should allow the owner to sleep better.;) VPS provides more freedom, isolation and security along with increased cost and responsibility.

When it comes to resellers selling reseller accounts, resource management is bound to be difficult. I suspect that a VPS, with better isolation and limited burst resources, would still be the better way to go.

VPS does not guarantee a fantastic server with Raid and all the rest of it. It isn't "VPS" that means you get good hardware, its the Host Provider themselves. You can get reseller accounts on servers with excellent "high-end" hardware too you know, just shop around. I am comparing VPS with reseller accounts, not dedicated servers.

The high-end hardware comparison was indeed a comparison of VPS vs low-end dedicated. The core advantage of VPS vs reseller is the isolation between customers. If one customer has load problems, that doesn't affect the other clients, while on a shared (reseller) environment it simply would.



You don't know for sure what level of isolation WHMreseller will offer in the near future so you can't really make a statement like that yet, wait and see first.

Well it surely won't give each customer a seperate filesystem, nor its own Apache/MySQL/Mail daemons, so no matter how you twist or turn it, there won't be the level of isolation that VPS technology offers. Sure there might be some isolation (probably based on max amount of sockets per client and things like that), but nothing that comes close to VPS technology.



I agree that VPS adds protection because it isolates each root users CPU, MEM etc but can you agree that on a bigger server with more websites (and clients) there is more chance of a ddos attack for that server? For example if you had a server with 1 website as compared to a server with 1000 websites there is more chance the server with 1000 websites will be attacked than the one with one website. If the attack was large enough then the single network card on the server would mean its possible the attack could affect all VPS accounts still since they all use the same single network card.

Well if the attack is large enough to take down a gigabit NIC, then it might also be big enough to take down the (edge) switch to which the servers are connected. In a case like that, not only the server which is being attacked would be affected, but also all other servers that are connected to the same switch. So in that scenario it really doesn't matter whether it's a shared, vps or dedicated environment.

Attacks generally aren't about bandwidth though, it's about the number of requests. The intention of a DoS attack is to send so many requests to the server that it won't be able to handle the processes anymore. Now the main advantage that a VPS has is that it has its own daemons/processes, while a reseller environment does not. Other VPS's could be somewhat affected by extremely high load on one particular VPS, however the impact would be nowhere nearly as big as on a shared hosting server, as in a case like that the other customers are running through the same webserver daemon.


Anyway I will conclude by saying - VPS is great technology. I have nothing against the technology, I only really have something against the pricing of virtuozzo.

Well the pricing of Virtuozzo doesn't really have to do with this thread though :) There are plenty of free technologies such as openVZ (basically the open source version of Virtuozzo, provided and sponsored by SWsoft), Xen, UML and a couple of others. The main reason companies use Virtuozzo is because it comes with commercial support (and thus with an SLA). The development of Virtuozzo costs a lot of money, and if it weren't for SWsoft, virtualization technologies wouldn't be anywhere as sophisticated as they are now (or well, it's hard to tell how advanced Xen would be then, but it's safe to conclude that SWsoft has contributed a great deal to the success of VPS technologies).

thanks for the explaination, pretty good.

Also, if I were to get a dedicated server, how could I configure the server to use VPS technology rather than cPanel?

Is VPS better than cPanel?

cPanel runs withing a VPS, it doesn't manage each VPS.

cPanel runs withing a VPS, it doesn't manage each VPS.

That one was already addressed a few pages back :)

Thanx alot Apoc for this great topic its really helpful .. and I still have some beginner questions.
what are the differences between them?
which one is better for a beginner?
is it easy to deal with?
is there not any explanation with images about how to deal with it?

Thanx alot Apoc for this great topic its really helpful .. and I still have some beginner questions.
what are the differences between them?
which one is better for a beginner?
is it easy to deal with?
is there not any explanation with images about how to deal with it?

Can you please eleborate those questions a bit? What exactly are you referring to with "them", "which one" and "it"?

Right now I really don't understand what you're asking :)

ohhh so sorry Apoc I forgot to write (reseller).:dI mean with these questions reseller and vpssorry again

Ah I see. Well the main advantages of VPS over a reseller account are:

- Much more isolation between accounts (each VPS has its own processes, ram, services, and even its own filesystem)

- If one account on the server has a high load, that shouldn't affect other VPS's. While on a reseller account, if one reseller account experiences very high activity, other reseller accounts would be affected by that too.

- You get full root access with a VPS, meaning you can configure everything to your liking

The main disadvantage of a VPS is that you will have to configure the environment yourself, unless if the host includes management. And even when the host includes management, you'd have to make sure they cover everything (e.g. full management). A fully managed VPS account will typically cost a bit more than a reseller account - that's mainly because of the fact that the management simply costs the host money.

As for what's better for a beginner: that depends. A reseller account should always be very easy to handle, but if you get a fully managed VPS and ask the host to configure everything for you, it should be just as easy to handle as a reseller account.

Regarding the images; you should probably get a control panel (like cPanel, Plesk, DirectAdmin, Helm, Interworx, etc etc) with your VPS, which is basically a GUI (graphical user interface). This way you can configure (almost) everything through a graphical interface. For instance take a look at www.cpanel.net - you'll be able to find screenshots there. Most hosts sell that control panel (or a similar control panel) with their VPS's for just a few euros/dollars per month.

thanx Apc alot for ur time and for these helpful information
by the way yesterday 1and1.com has begun its VPS hosting.
www.1and1.com (http://www.1and1.com)

can we trust those guys?

I think we can but for real I havenot tried them befor.

I can't really comment on them as I have no first hand experience with them. They're a huge company though so you should probably be able to find some feedback on the other forums.

If you want to discuss them, please use a seperate thread though :)

Just for those who understand French, go in fr.reseaux.internet.hebergement on Usenet, and you will see tons of people unhappy with shared hosing from 1and1. Note that I never tried the service myself. Also, the service in the US and with VPS might be totaly different.

Thomas

Hey, Firstly, i would like to say thanks for this great thread, i find it relevant to me, as im currently running a mid-end VPS, but i do have one question, My VPS has a 50% share of CPU and the server its on runs AMD athlon 64 Dual Core 2800+ , does that mean that i effectively have access to 1 of the 2800+ processors on my own, or does it mean i have access to effectively 2 half processors ? this does confues me, as in cpanel, it says 1 cpu.

second thing, you might of answered this question earlier, but i have 512mb dedicated RAM, and its burstable to 1GB (what does Burstable mean EXACTLY, i have heard a couple of rough definitions but im still not sure)

thanks,
amchost : )

thanks for this tutorial, i wasnt sure what a VPS was before, now i know what one is! thanks again

My VPS has a 50% share of CPU and the server its on runs AMD athlon 64 Dual Core 2800+ , does that mean that i effectively have access to 1 of the 2800+ processors on my own, or does it mean i have access to effectively 2 half processors ? this does confues me, as in cpanel, it says 1 cpu.

That depends on what technology your host is using. If your host is using Virtuozzo, you should be able to see both cores.

Also, are you sure you are only sharing the server with 1 other VPS? If so, I wouldn't exactly consider it a mid-range VPS since with most providers the VPS would share its resources with more accounts per server. Especially if you aren't paying a lot for your VPS, you may want to question whether you really are sharing the server with just 1 other VPS, because there might just be quite a few others without your knowledge.

second thing, you might of answered this question earlier, but i have 512mb dedicated RAM, and its burstable to 1GB (what does Burstable mean EXACTLY, i have heard a couple of rough definitions but im still not sure)

In short it basically means your VPS can use up to 1GB ram, of which 512mb is guaranteed to be available. Anything over 512mb *might* be available if other VPS's on the same server aren't using up all of their guaranteed RAM. For instance if there's another VPS on the server with 512mb ram, and it's only using 200mb ram, then the remainder would be available as burstable ram (usually devided equally among the other VPS's). At the same time that also means that there might not be enough burstable ram available sometimes.

The 512mb is what you can rely on to be available. You should be very careful with burstable ram as it might get simply killed off when there's not enough available. It should be safe to use it for peak usage, but if you consistently use more ram than what's guaranteed to be available, then you are basically putting your VPS's stability at risk.

Thanks for the reply, My VPS is openVZ based so i dunno if that allows me to see both cores, or not :).

Thanks for the advise on the scam, But the server is run by someone i know, and I trust him, plus, its a custom package, not something i signed up for . I suppose its quite a high spec Package, but you seem to be able to get some VPS machines with 1.5gb garaunteed RAM, 2.8 GHz, 100gb space, and 2000 GB bandwidth.

To be honest with you, if i wanted a machine like that, i would go for Dedi every time :) the prices are similar.

Thanks for the info on Burstable Ram, I dont use above 512 mb anyway ( as a rule ).

With openVZ you should be able to see both cores. As far as I know it's not possible to let openVZ only show you one of the cores, unless if that was recently added to the software.

It could be that the machine maybe isn't a dual core machine afterall, or it could be that the host has turned of dual core functionality in the BIOS. Either way, your best bet is to simply ask your host about it.

yeah, ill do that, is it possibe to fabricate the information shown in the server info page on whm ?? because it says dual core there :) thanks again

Since linux is opensource, ultimately everything can be fabricated. It's unlikely that they have done that though, especially since you indicated you trust the host.

Also, if I were to get a dedicated server, how could I configure the server to use VPS technology rather than cPanel?

Is VPS better than cPanel?

A dedicated server and a VPS can generally run the same software. For example, on your dedicated server you can run cPanel (a control panel, which has nothing to do with VPS's btw), Plesk (another competing control panel), or even Webmin (yet another CP), and much more. You can run the exact same things on your VPS as well. A general rule of thumb is if you need to modify your Linux Kernel to run something, you cant neccessarily do it on a VPS (unless its something like IP_TABLE entries or specific network permissions, which can be done by your VPS provider on the host node side).

VPS technology just means the type of virtualization software out there. For Linux platforms, the most popular one is Virtuozzo, but Xen is also catching in popularity but fewer hosts offer that than Virtuozzo. On the Windows platform side there is Virtuozzo as well, but also VMware and Microsoft Virtual Server R2. Each on its associated platform has positive and negatives. There are many threads on the VPS forum on which VPS technology works best.

-Sean

Isnt it like a dedicated server but many dedicated servers in one place?

Isnt it like a dedicated server but many dedicated servers in one place?

No not really. "Dedicated" implies that the hardware of the server is dedicated to one client, which isn't the case with VPS's. You could see it like a dedicated server being cut up in slices, and each such a slice is a VPS. Each VPS operates completely independently from eachother, yet still they use the same physical machine.

Thanks for this again !

Very nice VPS tutorial i ever seen in my life.

Thanks fot the "tut" it was very helpful , just emailed it to a friend of mine. :agree:

Very helpful explanation on what is a VPS. Good job.

Hi,

Thank you very much for your article..

I am planning to buy a VPS for my vBulletin forum.. It's an average forum with around 50 - 150 users online in last 15 minutes.. The D is around 200 MB & i'm using vBSEO also.

What config you recomend for a VPS package? Will 256 enough if i'm using cpanel also?

Thank you..

If there's a lot of database activity, I would recommend to go for 384mb RAM (especially considering that cPanel by itself uses up 100-120mb ram). 256mb should probably work too, but 384mb would be safer.

What you could consider is to get a VPS with 256mb first and monitor your resource usage. Then if it turns out that you need more ram, you could simply upgrade the VPS

If you aren't sure about things like these, it's probably a good idea to go with VPS host that provides a managed solution, as they should be able to assist you with optimizing your RAM usage and make recommendations on what to do.

Good luck!

Thnks this a very nice explanation of VPS very beneficial for Newbie as me.

Haha very good. I usually never buy a vps unless the company owner was a member of WHT.

Thanks for the time spent on this tutorial...I've learned a great deal

If there's a lot of database activity, I would recommend to go for 384mb RAM (especially considering that cPanel by itself uses up 100-120mb ram).



Which panel uses the least resources, PLESK or Cpanel?

Also, just curious on how many VPSs per server would be considered "To many" on a low end and high end server?

Which panel uses the least resources, PLESK or Cpanel?

Usually Plesk uses the least. Plesk comes with the benefit that it's based on a templated architecture, which enables it to share the resources with all other Plesk VPS's on the same server. Thanks to that, the usage per VPS is lower - but this is only really effective if you run mutliple Plesk VPS's on the same machine.

Also, just curious on how many VPSs per server would be considered "To many" on a low end and high end server?

It's not really possible to give any hard numbers for that, as that depends on a lot of factors. It depends on the size and activity of each VPS, and how much the server can handle (which relies on CPU, disk I/O and RAM). The only way to find out what the limitations are, is to test your configuration by creating a certain amount of VPS's on the server and push some load onto them - and then just monitor the load and lags.