VMware disk partitioning

[techmen8080]

Greetings all,

I have the following new system (see below) on order (with 16 MB of ram and three 80 GB hard drives):

I want to run up to 30 virtual servers for various (VLE) Vitural Learning Enviroments.

I have been told the free version of VMware will work. Though it comes bundled with VMsphere4. I am not sure about the licensing issue or the cost between the free version and VM4.

Anyhow, I need to know how to partition the hard disks to work best with VMware. I have three disks and of course one is for backup.

Is there a manual for this or does anyone know a standard way to do the partitioning. I am having the server sent to a data center and not sure if it will come with VMware manuals or not. I rather think not.

What is a good simple partitioning scheme to get me started?

Is it worth me buying a license for VMsphere4 with running just one server .

Thanks to all that have time to answer, techmen

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STIRLING 123 DUAL XEON VMWARE CERTIFIED SERVER

PROCESSOR Dual 771-pin LGA Sockets

Supports up to two Intel® 64-bit Xeon® processor(s) of the same type:

Quad-Core Intel® Xeon®Processor

5400/5300 sequence

Dual-Core Intel® Xeon®Processor

5200/5100/5000 sequence

CHIPSET Intel® 5000P (Blackford) chipset

1333 / 1066 / 667 MHz FSB

SYSTEM MEMORY 8 x 240-Pin DIMM Sockets

Up to 32GB DDR2-667/533 FB-DIMM (Fully Buffered) ECC

Dual channel memory bus

ECC FB-DIMM DDR2 Low Profile SDRAM ONLY

2-way interleave provides outstanding memory performance

(memory must be used in pairs)

ON BOARD I/O ATI ES1000 controller 16 MB PCI graphic controller

2 Fast UART 16550 serial (port + header)

5 USB ports (3 headers/2 rear ports)

PS/2 keyboard and mouse ports

ON BOARD IDE Single EIDE channels support up to two UDMA IDE devices

Supports UDMA Mode 5, PIO Mode 4, and ATA/100

ON BOARD LAN Intel® (ESB2/Gilgal) 82563EB Dual-Port Gigabit Ethernet Controller

Supports 10BASE-T, 100BASE-TX, and 1000BASE-T, RJ45 output

Intel® I/OAT support for fast, scaleable, and reliable networking

ON BOARD SATA

SATA RAID Intel SB SATA 3.0Gbps Controller

RAID 0, 1, 5, 10 support (Windows)

RAID 0, 1, 10 support (Linux)

Six Serial ATA ports

Four Hot-Swap SATA hard drives supported

1U SATA / SAS Backplane w/ SES2 Enclosure Management

SAS RAID Controller required to support drive arrays using VMware

[RParker]

ESX Free version has some limitations, 1 vCPU per VM, and I think 2GB of RAM. So you have no alternative for backup? Each server has to backup the data? I would advise using the disk space for VM's, and making the 3 disks one large drive to put the ESX local datastore. You can't do 2 disks and the 3rd one as blank, once ESX is installed you can't really use it for anything else at that point anyway, so nothing else can 'use' that space but ESX (at least not easily).

Buying a license is up to you, if you feel you need more than 1vCPU for a VM then yes, otherwise with just one server the FREE version may be ideal.

[curlet91]

I agree with this setup. To elaborate, you'll want to more or less accept the defaults provided by the partitioner when you install ESXi 4.0 (/boot, swap, etc). I tend to change the root (/) partition from 5GB to 10GB in case I need the extra space for ISOs, patches, or whatnot. I typically also create a separate 2GB partition for /var/log as a "best practice." Finally, your VMs will be stored on a /vmfs partition, which should account for the bulk of your remaining storage space. Hopefully this helps a bit.

-Tim Curless-

-VCP-

[techmen8080]

Thanks so much for repsonding. I am very new to all this. I am not sure how 1virtual cpu per VM relates to the physical cpu ( the system will have two quad core Xeons) and how that in turn relates to Vms running.I am reading ohter threads on the forums to try to understand this.

I gather from the 2 MB of ram that a 16 MB system would then only be able to host 8 VMs?

If all the three 80MB hard disks would be formatted as one VMdiskspace and none could be used as a backup drive, then I wondering the use of having three instead of one 360MB drive. It seems three dependent drives increases the chance of a failure rather than offer any protection? Would one drive by faster?

Also how do I do backup with only one physical server and all three drives acting like one disk space?

[techmen8080]

Thanks Tim,

I really appreciate your response. I will use your suggestions. Also, could you point me int the direction of a few good documents that explain how this works. I saw there are pdfs available in the documentation section of this site. Are there any other docs that explain how the disk partitioning works.

[curlet91 · Accepted solution]

The install guide in the documentation area of the site will give you some pretty good insights as to how basic setup and administration works.

There are also some great books out there to get your feet wet. Scott Lowe has a book coming out this fall called "Mastering VMware vSphere 4." Also, the technical design guide by Herold, Oglesby, and Laverick is great for learning the basics about the "core four" (CPU, memory, disk, network) as they relate to ESX. It hasn't been updated for ESX 4 yet but many of the concepts are the same. That's just a couple of the many good VMware books out there.

-Tim Curless-

-VCP-

[curlet91]

I'm by no means an expert, but here's a brief rundown that might help.

Each VM will have one vCPU (as RParker mentioned, a limitation of ESXi) which will get scheduled access to the physcial CPUs via the hypervisor (the ESXi layer running between the hardware and the VMs). You have the ability to create affinities saying "VM A your vCPU always executes on physical CPU 2, core 3" etc. However this is an advanced setup and it's usually better to let the hypervisor handle CPU scheduling.

In terms of memory, you can actually create as many VMs as you want. As you power them on you will notice your physical memory resources being consumed. However, ESX allows you to "overcommit" memory. For example you may have 8-2GB VMs running on a host with 16GB of physical memory. Powering on additional VMs would be allowed, however when you get to that point you will likely start to see performance issues. Multiple VMs of the same guest OS type will actually try to share common processes and in turn reduce their memory footprint. This is why a 2GB physical machine may actually be virtualized with less than 2GB of virtual memory. I wouldn't recommend running things this tightly if at all possible. You want to leave yourself some room for growth.

You will have to look at your VM requirements when it comes to disk space. If you have 3 80GB hard drives that you put into a RAID 5 configuration you're looking at about 160GB of usable space. Take away 15GB or so for the hypervisor and related components and you're left with about 145GB for VMs. If you really want to run 30 VMs on this one host you're looking at less than 5GB per VM, and no space for backups. You might need to consider a fourth hard drive and an external backup solution.

There is a good deal more you should read about if you get the chance (see my previous post).

-Tim Curless-

-VCP-