Web Hosting Talk : Web Hosting Main Forums : VPS Hosting : Max VPS on 1 physical host.

[bublers]

I'm trying to avoid from getting into any trouble in future, so I would need some advice from any of you who have experience in VPS hosting.

1) What is the limit for total of VPS can be hosted on 1 physical machine.

Physical machine spec :
Two (2)Intel Quad Core
16GB redundant DDR3 RAM (max 64GB)
(4x 1TB SATA 7.2) RAID 5 attached to PERC 6/i
SolusVM on Centos

I hope the supplied info is sufficient.

Thanks !

[PCS-Chris]

Depends on the size of VPS/usage etc. However based on RAID-5 I would suggest no more than 30 VPS.

You would do better to reload the machine and do RAID-10, as the IO requests per second is what counts, when you have data on all directions of the array being requested by VMs.

[Douglas]

With all due respect, I would shy away from any provider that doesn't know how best to determine the number of customers per physical system and has to ask publicly for a magical formula.

This is actually a pretty common situation to sort out, based on experience in the industry. If you don't know the answers, you need to get someone on your team that DOES know.

I apologize if this post comes off a bit strong, however, this concerns me that someone is entering a market that they know little about. And for some customers, if what you do breaks their system, that's their livelihood that you hold in the palm of your hands.

[bublers]

Hi Chris,

Thanks for the quick respond.

For the sizing concern :
1) Each package is 100GB + 1GB

Raid :
Here is the thing, not this machine, but i'm working with SUP-V somewhere else.
Each provisioning is being used by only 1 host each time.
So what happen is we prefer RAID 5 so we can have 3 spindle instead of 2 (raid 5 instead raid 10)
The parity check for read should be overcome by the supplied steady state came with the PERC card.

In this case PERC 6/i which came with 256mb attached which is good but I'm very worry about the average of IO does by VM which I'm not experienced with.
I'm hoping this PERC can provide high RH.

Please do correct me if i'm wrong.

In short, i'm planning to allow only max of 16 host on each physical.

Thanks Chris!

[bublers]

Originally Posted by Douglass of Eggnog

With all due respect, I would shy away from any provider that doesn't know how best to determine the number of customers per physical system and has to ask publicly for a magical formula.

This is actually a pretty common situation to sort out, based on experience in the industry. If you don't know the answers, you need to get someone on your team that DOES know.

I apologize if this post comes off a bit strong, however, this concerns me that someone is entering a market that they know little about. And for some customers, if what you do breaks their system, that's their livelihood that you hold in the palm of your hands.

Hi Douglass ,

Thanks for the nice comment Douglass, me myself understand where you are coming from, but no worry, this is not a public VPS, this is very much for our local corporate service.

We host physical server & planning to move everything into Virtual Machine.
Why we pick SolusVM over ESX is because it can work with WHMCS which can help us with the billing so much.

Thanks !

[Nnyan]

@PCS-Chris

I could be wrong here but I thought that generally RAID 5 had higher I/O reads while RAID 10 had higher I/O writes.

@bublers
So are you planing on selling sixteen 1GB VPS accounts on a 16GB server or do you plan on adding more ram as you fill it up?

[bublers]

Hi Chris,
One way is for us to decide now on how many physical machine needed.
Second is to move around the V machine as we go if we felt like there is a resource waste on each physical.

Preference is not to go with the 2nd option.

The idea is 15 over 16. (1gb for the host)
So if 16 is not a good number, we will go down to 8 (2GB each).

This capacity plan is just to avoid any resource wasted on the investment.

p/s : the RAID 5 & RAID 10 will take us forever just like others, so I skip that sorry.

[Douglas]

bublers, that changes the overall tone of my reply then, and I am sorry about that.

I still would recommend that you have someone on your team that is very savvy with virtualization assisting you with this.

As someone else pointed out, it's all very dependent on what virtualization you're using and what each VPS itself is doing.

What works for one person with 30 VPSs may not work for someone with 12 VPSs.

From a hosting standpoint, it's really up to each host to determine current resource utilization as far as deciding how many individual VPS systems to run on a physical machine.

Happy Holidays!
(See, I'm not TOTALLY a grinch, haha!)

[bublers]

@Nnyan
Very sorry for the mistake replying to Chris for the reply done by you, I'm very new to WHT, sorry for that.

[bublers]

Hi Douglass,
No worry mate, my problem is that I have 2 job haha !

One which I work with all those enterprise solution (you name it.. XP2400, SUP-V, HP-UX, ESX, blablabla & etc.) Where all application running on those storage boxes & only the OS sitting on the VM, any application performance issue can be resolve easily (migrate raid type & etc)

Getting involve with this new environment with Open System where cost constrain is a concern & browsing all posts in this forum, it does tell me that experience from Open System experts like you guys must be appreciated in all manner.

Instead of getting into the trouble I would prefer to come as an empty bowl & ask

Still dont have any conclusion yet, but the most important what I can see is that VM in Open System is being limited by disk I/O, so I would need to work on gathering the average number & do the math.

Thank so much.

[funkywizard]

I would also recommend raid 10, as that will give better overall performance for both reads and writes, so long as you don't need the space you'll be giving up on the extra drive.

Other than that, if the physical machines you're replacing need 1gb of ram, you could put 15 of them on there so long as they aren't too heavy on the cpu or i/o. There's no harm in dedicating 2gb ram to a VM, as I find a lot of cases things run a lot better with more than 1gb ram, even lightweight applications. This is especially true if you're having i/o problems, as the extra ram will automatically be used for file system caching if your os isn't using it for anything else.

But as in all other things, your mileage may vary, and you'll really have to get a feel for the requirements of your servers in order to know.

Does anyone have a good rule of thumb for what kind of performance hit you take by virtualizing instead of doing things on physical machines? Maybe that would make things easier to figure out, as hopefully you know what kind of loads your physical machines are under currently.

[bublers]

Same concern on performance.

What I dont like about ESX is the USB part where all data copy need to be done through FC / Pair / IP.

Thanks for the RAID recommendation!

bublers

[bublers]

Guys, just an update,
I go with RAID 10
Now init at 30%

hahahah this is freakin damn real update :p

[funkywizard]

What do you mean?

[bublers]

I'm a RAID5 fan when doing enterprise support (which require more read than write)

Two including you yourself who are involved very much with OpenSystem recommended RAID10.

Today is Xmas & i'm in Datacenter doing the installation, with nothing else better to do so I just put something on the wall regarding the choice I've made on the RAID preference.

Nothing important, just got addicted to WHT, thats all ... :p