VMotion

[jibey_jacob]

I've been reading a bit about VMotion and the ability to move VMs around nodes on a network if that's needed. I would like to know if the underlying techniques for this feature require that all physical hardware (PCs) that's needed for this always have to be online. Are there some kind of hardcoded factors in VMotion that would require that all those PCs always have to be available?

Here's what I want to do: I would like to take PCs on entire IP subnets offline - power off, with the capability to bring them online through Wake-On-LAN - when there's less load on the network and bring them back online as more load hits the network. Can VMotion make this possible?

Thanks.

[Gerrit_Lehr]

I didn't really get what you want to. What PCs? Esx Servers? You can use VMWare DPM to move VMs off a ESX Server and shut it down if the load is so low that the Server is not neccesary. Than DPM powers them on again via WakeOnLan when the Server is needed.

VMotion itself requieres licensing and a shared storage seen by all involved ESX Servers, on which the VMs are stored. Also, the VMKernel network stacks of the ESX Servers must be configured and reach each other.

Kind Regards,

Gerrit Lehr

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[williamarrata]

Here is some documentation on VMotion.

Hope that helped.

[jibey_jacob]

I would use some blade servers from HP or IBM. I'm not sure yet about what ESX servers I would use. But here's what I want to accomplish: there would be periods of time in which the load on my networks would be low enough such that I wouldn't want all my hardware up and running. With the kind of abstraction that virtualization offers, I was wondering if it's possible to manage my network in a way - all management through software, I wouldn't want to issue the Windows Server 2008 shutdown.exe command myself - such that some nodes are taken offline during off-peak periods and bring them online as more load hits the network.

Is this possible through VMWare technologies? Obviously, those VMWare technologies must have some way to determine the load on those VMs, etc.

[adolopo]

Within the realm of ESX? I don't believe there to be an option for what you're asking for. For most people here, a good majority would wonder why you'd want to do this at all (as it's not something that's considered "standard"). Which is not to say that it isn't possible.

If I had a need to do this though, I'd script (then CRON) the VM's to VMOTION off the HOST, then do a graceful shutdown of the HOST.

For powering the server back up, I'd explore the possibilities of the HW vendor (ie. ILO, etc).

[crazex]

VMware doesn't, currently, offer anything that is exactly what you are looking for. I agree with the earlier post where somebody suggest DPM(Distributed Power Management). What this does is polls usage of your ESX hosts, and shuts them down automatically when they are not being utilized. I'm pretty sure when the shutdow is issued it will migrate all the VMs on the machine to other hosts, and then shutdown. Remember, with ESX/VI you don't need to worry about the individual VMs eating up power, per se, but rather the ESX hosts. With VI you can definitely automate this, so that hosts are always on during business hours, and then shutdown/consolidate during off hours. Like I said, I know this isn't exactly what you are looking for, but it should serve the purpose. The most important thing you need to remember is that VMs are not the same as a physical Server/Desktop, so you don't need to worry about them so much, when it comes to power/usage consumption.

-Jon-

VMware Certified Professional

[jibey_jacob]

I've explicitly stated that I wouldn't want all my "hardware" up and running all the time, so clearly I'm not talking about VMs using up power.

The reason I want to do this is to better conserve energy in my datacenters. I don't see why this is diffcult for anyone to understand. This is exactly the kind of thing that should be done with intelligent software.

[Ken_Cline]

There is currently no means - other than custom scripting - that would allow you to shutdown Windows systems to conserver power. The beauty of it is that you don't need to. With Distributed Power Management (DPM), your VI will monitor itself and automatically consolidate VMs onto as few hosts as possible and suspend hosts that aren't needed at the moment.

From http://www.vmware.com/products/vi/vc/drs.html

VMware Distributed Power Management (DPM) (this functionality is supported experimentally) continuously monitors resource requirements and power consumption across a DRS cluster. When the cluster needs fewer resources, it consolidates workloads and puts hosts in standby mode to reduce power consumption. When resource requirements of workloads increase, DPM brings powered-down hosts back online to ensure service levels are met.

Distributed Power Management allows IT organizations to:

• Cut power and cooling costs in the datacenter during low utilization time periods.

• Automate management of energy efficiency in the datacenter.

Ken Cline

Technical Director, Virtualization

Wells Landers

VMware Communities User Moderator

[crazex]

Wow! Way to call me out, when you are the one who doesn't seem to understand what is being said. If you use the DPM feature with VI3, you WOULD save power, as your ESX hosts would be shutdown. What I think you need to do is actually sit down and do some reading on how the VMware product works. I understand what you "want" to do, but what everyone here has tried to tell you, is that it isn't "exactly" possible. With ESX/VI3 the host machines(ESX servers) are using the power. You won't exponentially increase your power usage by running more VMs on one server. If you still refuse to understand what we are trying to say, at least listen to Ken.Cline, as he is correct in saying the only way to accomplish "exactly" what you want to do, would be to do some custom scripting.

-Jon-

VMware Certified Professional

[jibey_jacob]

When you say that what I want to do isn't possible, are you saying that ESX hosts can't be shutdown, like what shutdown.exe does? Why not? Can they only be suspended? Perhaps that's not much of a difference.

But I think that it requires human intervention to wake up a machine that was suspended. Whereas, if it was shutdown, you could use Wake-On-LAN. Or perhpas you could use Wake-On-LAN to bring alive a machine that was suspended. I'm not sure.

Please clarify these points.

Thanks.

[weinstein5]

As ken indicated to shut down the vm's so you can do a wake on LAN would require some custom scripting - but the ESX hosts would remain up - VMware solution DPM actually builds on the DRS - as the load drops on the VM's DRS/DPM will vmtion the VM's and there will come a point when an ESX host or hosts no longer had any VMs on it at which point DPM will power off that host or hosts - if the load starts to increase on the vms DPM will start powering up hosts to handle the additional load - using DPM allows you to shutdown and restart them with out human intervention and based on the resource load of you vms

[jibey_jacob]

Is there some way to intervene in this process of VMotion where VMs are moved around, and even taken offline? I might be using Microsoft System Center Configuration Manager to apply some critical updates to my guest OSes, so I might actually want all guests to be available when I want updates to be applied.

Thanks.

[crazex]

Yes, you can definitely patch all active VMs. Can you explain why you want to shutdown the VMs? I understand that you want to conserve power, but like I stated before, the bulk of the load is in the ESX host, not the VM. When VMs are being VMotioned, this process is seamless. The only thing that happens is an ARP refresh. I have no problem using WSUS to update my VMs, and I've VMotioned them numerous times. As long as the VM is powered on, it will be unnoticeable. If you have you VM powered off, you would need ot power it on to use SCCM to apply patches/push out software.

-Jon-

VMware Certified Professional

[Ken_Cline]

At this point, I think you would be well served to take some time to read the links that williamarrata and I have provided for you. It would also be beneficial for you to do some research on VMware Update Manager (VUM), which might be an option for you to patch your VMs (even the ones that are offline/shutdown).

Ken Cline

Technical Director, Virtualization

Wells Landers

VMware Communities User Moderator

[jibey_jacob]

Please read my other posts. I've explicitly stated that I wanted the "hardware" shutdown, not VMs.

[jibey_jacob]

If you guys want to look like experts you must answer questions, and that's what the forums are for. Do my questions cause you any uneasiness? I think they've been technical questions.

If I had the time to read lots of documentation, I wouldn't be asking questions on these forums.

Nevertheless, VUM sounds like it could be viable for the purpose of applying updates.

[williamarrata]

Jibey, I think we have answered your Question very well so far. Here's your first question;

"I've been reading a bit about VMotion and the ability to move VMs around nodes on a network if that's needed. I would like to know if the underlying techniques for this feature require that all physical hardware (PCs) that's needed for this always have to be online. Are there some kind of hardcoded factors in VMotion that would require that all those PCs always have to be available? "

The answer to this question is two part

1) All PHYSICAL, NOT VM'S must be on to be able to be part of a cluster to VMotion the VM's from one to another. If you have more than 2 Hosts then you need to make sure that if you turn off the one host that the other two can handle the load of the one turned off.

2) If you turn off a VM, It will NOT VMotion and if you've turned of the host that the VM is residing on, the only way you will be able to get it powered back on is to Add it back into inventory and power it back on.

Now, Ken.Cline has given you excellent feed back to your senerio, and given you documents to do your due diligence, but if we don't have the EXACT answer you are looking for, please refer to VMWare's Helpdesk and see if they can help you with your situation.

We are all here in this Forum trying our best to help people as much as we can before it gets to a level of the need of a call to VMWare helpdesk. But there are times that we just can't help but we do give it our best. I hope all the information we have given you so far has helped you.

Hope that helped.

[crazex]

I've also stated in 3 different posts, that DPM (Distributed Power Management) WILL IN FACT SHUTDOWN THE HARDWARE, thus conserving power in the data center. I'm just not sure how else I can make that point clear. When I started with VMware, I sat down and read nearly every document that VMware published, and supplemented them with info from the forums. If you are unwilling to use the vast information that VMware provides, you should probably think twice about deploying VI, as it requires a completely different thought process than traditional servers.

-Jon-

VMware Certified Professional