New to Virtualisation - strategy

[Grenage]

Greetings; firstly, I apologise if this is the wrong forum - there are so many!

At the moment we have around 30 servers, all running on their own physical units.  While we aren't thinking about moving everything across, I'm writing up a budgeting plan for new hardware and licensing, and virtualisation is the way I'd like to go.  I'll get an expert in, if need be, but I really need to have as good a grasp as possible before we get to that stage; I recently installed a unit with vsphere free edition, and it seems decent.

Uptime is important (when isn't it?), but cost is a big factor; I suspect I'll need to go in with two main strategies and see what they go with - that's what I'm trying to do now.  Sorry for the boring back-story!  I'm not after a spoon-fed, hand-holding, just a steer in the right direction.  The Essentials Plus pack looks like a reasonable option, so I'm looking at two or three servers, maybe R710s; here's my understanding of what we'd be looking at:

High-Uptime:

Vmotion would be required, which means that I need NAS, not DAS.  iSCSI looks reasonable, but I'm slightly worried about bandwidth; with 10Gb switches costing so much, I might as well look at an 8Gb fibre switch, such as the Brocade 300.  Vmotion can't work with local storage, so I'd need a couple of NAS units (perhaps Dell MD3600f) with a couple of connections from each server.  The server images would have to replicate across the NAS units.

Cheaper:

DAS (MD1200) connected to each server, so no additional outlay on switches and fibre modules.  Images could be backed up on local storage, and in the event of server failure, its DAS could be connected to one of the other servers, and the VMs run there temporarily.  I may be able to get away with essentials, rather than essential plus.

How far off is my understanding?

[marcelo_soares · Accepted solution]

I think your approach is good, but I would not think in using DAS (as it will limit you so much). The pack Essentials + iSCSI seems to be the cheaper one you will get (I also had my concerns about Gbit in the past, but I think you should give a try on this case - 30 VMs should not generate a huge load on the gbit channel, and you always and easily can add an extra path and manually balance the load). If you want automatic HA, you will need the essentials plus, but if you don't mind wake up at the night to manually failover your machines in case of trouble, yor are good to go.

Also one detail: MD1200 is not supported for any vSphere versions, so always check www.vmware.com/go/hcl before starting to think on hardware. The MD3600 is supported either in FC and iSCSI.

If you need any further information, let us know.

[Grenage]

Hi there,

Thank you for your reply, it's good to know I'm not too far off; there's a lot of reading to do.  I'll write off the DAS option and cost up iSCSI and Fibre, then at least both options have been presented.

Again, thank you!

[Nikhil_Patwa]

Hi,

Welcome to VMware Community and Virtualization.

I suggest you first gather information of all your 30 physical servers in terms of CPU and RAM utilization as that will give you the base to consolidate into virtual machines.

VMware vSphere Essentials Plus kit comes with 6 processor licenses and max 3 hosts i.e each server with dual processors; vRAM entitlement of 32GB per processor therefore max 192GB RAM. This information should give you some background comparision with your existing 30 physical server.

Read on the following article

http://www.vmware.com/files/pdf/vsphere_pricing.pdf

I also suggest you install ESXi free version first and try to do P2V (Physical to Virtual using VMware Standalone Converter) of your servers as this will also give you information on how much resources are being utilized by virtual machine compared to physical server.

Once you are confident with managing and administering virtual machines then move forward to deploy more ESXi hosts, vSphere Essentials Plus with vCenter Server (advisable to have vCenter Server VM in a separate physical server apart from the physical servers hosting your VMs)

Start slowly, gain confidence and then deploy full scale.

Hope this information is useful

Nikhil

[Grenage]

Hi there,

Thank you for the information and links; I wasn't aware one could convert a physical install to a virual image, that's good to know!  I'll have a play with it and see how much damage I can do.

Russell.

[Nikhil_Patwa]

Hi,

P2V is a very handy tool and infact you will love it coz that way no installations are required, all physical settings are in your virtual machines.

Am sure once you get a hang of the conversion within no time all your systems will be virtualized....welcome to virtualization

Best of luck.

Nikhil

[jeff9565]

Russell,

Couple of things that I've run into in my days:

1. For 30 VMs - Don't worry about 1Gbps not being enough.  Whether you use iSCSI or NFS.

2. Make sure you think about traffic segregation (vMotion, Management, VM, Storage).

3. If you do not have a SAN infrastructure today, using FC may be more costly as you would need to get FC switches.

4. As far as storage - depending on your IOPs requirements, the VSA may be an option for you that is also cheaper than buying a NAS / SAN device.  Make sure you read the documentation before choosing to go with the VSA.  There are quite a few "gotcha's."

5. As someome mentioned above, do an assessment of your current physical infrastructure.  You will need to engage a VMware partner to do this but they can run Capacity Planner on your network for a month which will give you a lot of nice metrics and cosolidation ratios.

6. You are talking about replication but I am not sure what the purpose is.  DR or just local recovery?  If you are thinking about local recovery, I wouldn't spend money on 2 NAS devices that will be sitting in the same location for backup purposes.  Buy a fairly redundant storage array and use VDR to back up your VM images.  If you are doing DR, well that is a completely different story.  If the storage platform that you get does not support replication, you can use a new feature in SRM (Site Recovery Manager) called vSphere Replication that will automate this for you.

Hope this helps.

Jeff

[Grenage]

Great info, thank you.

The main reason I was looking at a second NAS, was to avoid a situation where the NAS fails and we are dead in the water.  I suppose a backup unit doesn't need to be of the same scale as the primary unit, which would save some cash; we just couldn't afford to be down until the unit could be replaced.

[Jim_Stiveson]

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