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I am using vmware in my home and i have 8Gb RAM. I was thinking that in Practical or enterprise who hosts the VPS. How much is their configuration in terms of RAM and processor. And usually How many Virtual machines are installed or recommended on One Computer


Server that can support about 50 -60 Virtual Machines

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Everything depends on the workload of the VM's - in an average server environment I'm generally aiming for no more than 30VM's per physical server and choose to scale out (ie add more physical boxes at that spec) rather than up (buying fewer more expensive servers) but even that depends on what the customer wants.

The systems that I've seen running more than 50 (server) VM's are things like the Dell M905 Blades - these take 4x Opteron 83xx (4 Core) or 84xx (6 core CPU's) running at 2.1-2.9Ghz. Total RAM on these can go up to 196GB or Dell's R900\R905 which are 4U rack mounted 4-way systems running either Intel (7400 series Xeon) or AMD (83xx\84xx Opteron) processors, again supporting large amounts of RAM (up to 256GB RAM). These were generally sized to run 50-60 VM's under normal conditions but capable of running double that in extreme situations when some hosts in a cluster are down. A fully configured R905 with top of the line CPU's, fully populated with RAM and with both MS Server 2008 DataCenter Edition and full licenses for ESX 4 Enterprise plus will set you back the best part of $90k list.

VMware will support up to 25 virtual CPU's per physical core with ESX 4 update 1 so (in theory) you could have 200 VM's on a dual Quad Core system. That would be pushing it a bit too far for Server virtuaization scenarios but for desktop virtualization you can easily see > 100 VM's on a dual socket system that isn't under any particular stress.

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wow that was info i was looking. SO do you backup all that server to something else or take snap shots of all VM daily. I wnat to know to they handle backup of that big server – John Dec 19 '09 at 22:46
All the VM's in those environments are stored on large SANs - EMC Symmetrix or similar, in one case an Equallogic group with 11 arrays on the primary side - budget around $250-500k for the main storage. All storage in these environments is aggressively mirrored to a secondary site and the whole environment is covered by something like VMware SRM to enable rapid failover. Environments at that scale target very high service availability but it costs a lot - an R905 configured to the max and licensed for VMware Enterprise Plus and Microsoft Datacenter Edition doesn't leave much change from $80k. – Helvick Dec 20 '09 at 1:53

The answer to this is really "it depends." I'd say if you took a poll you would see everything from old multi-cpu single core machines with 4-8GB of ram all the way up to 4 way nehalem machines with 256GB of ram. As far VMs per host ... that really depends on the host and how many machines it can handle. I've seen everything from and ESXi box running 1 vm (to get around a hardware compatability issue) all the way up to monster servers hosting 50-60 VMs each.

EDIT: in response to the question:

I've seen 50-60 workstation images running on a Dell M600 Blade server with 24GB of ram and the E5506 Proccessor (They were bought before the Hyper threaded models came out)

We also have about 40 Servers running on the same type of host with 48GB of RAM.

My friend has a server (don't know the model) at his office that is a four way opteron systems with 196GB of ram. Not sure how many VMs they are running off it but i'd bet it gets up to the 50-60 range

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SO yes Basically i would like to know the configuration of Monster server u are talking about with 50 - 60 VMs – John Dec 17 '09 at 1:27

We offer dedicated virtual servers to our larger customers and generally plan on a single core per VM (as many VMs are quite low usage) and an average of 4GB per VM. So the machines we're buying now (HP BL490c G6's) have 16 effective cores so we put 72GB (18x4GB DDR3) inside.

Oh and we put no more than 6 VM's (at an average of 50GB+4GB-memswap) per 500GB LUN (we use HP XP/EVAs with R1 arrays using 600GB 15krpm FC disks). We only use thin-disks for development environments, where we're happy to increase the VM/host and VM/LUN ratios.

For internal systems we tend to bank on 2 cores and 8GB per VM.

Hope this helps in some way.

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