Type 1 Hypervisors?

[Asphodelus]

I'm trying to decide between Hyper-V and Xen. Would anyone with experience with one (or both) like to weigh in with their thoughts on the pros and cons of each?

 

[yinan]

Neither. ESXi it it superior to both.

 

[Chiefcrowe]

Hyper-V is pretty good. With System Center, it has good management tools, and I have been able to host VMs on an iscsi SAN. We get great microsoft pricing so it is a good deal that way too. We have probably about 10 VMs on there with no performance problems, etc.

I thought it was relatively not too difficult to set up the system and the learning curve isn't too bad. I haven't tried the 2012 version but that is supposed to be better than 2008. I'd recommend trying it out to see how you like it. Oh and the more RAM you can get the better - I ended up having to add 48 GB more memory and it was more $ than if I bought it originally.

 

[imagoon]

I have no idea on Xen but once you get to Hyper-V to ESXi, when you finally get to the apples to apples comparison, they end up costing the same to implement. Xen is a bit more of an oddball because Xen is free but the management tools border on junk. Citrix XenApp however takes the free Xen server bolts a bunch or tools on top of it to make it closer to ESXi / VMWare. However you have to pay Citrix for this feature. I am not that aware of the tiers with XenApp though.

 

[Asphodelus]

Sorry, I should have mentioned 2 things:

1. The server itself is a Dell PowerEdge C1100 with 2x Xeon L5520 and 72 GB of RAM. ESXi, Xen, and Hyper-V are all officially supported, but...
2. This is for a home environment. The cost would have to be on the level of a shrink wrapped DVD on Best Buy's store shelves, rather than a multi-year enterprise software license agreement. Realistically, given the pricing model for type 1 hypervisors, it basically has to be free. The reason why I didn't mention ESXi is because full versions of Hyper-V and Xen are available for free, whereas the free version of ESXi is lacking a number of important features.

 

[imagoon]

Free license of ESXi5.5 $0 and no Ram limit anymore.

 

[Asphodelus]

There's no hardware limitations anymore, but there's no high availability features in ESXi free either - at the very least I need vMotion so that I can actually shut down or reboot one of my C1100s without taking down my entire network.

 

[smakme7757]

Edit: Saw you wanted HA. In that case you need shared storage if you want 0 downtime.

However Hyper-V replica would most likely give you what you need, but it isn't HA. You replicate your VMs from the primary server to the second server. So it's like a mirror. Then if you need to do maintenence on one of the hosts you just initiate a planned (or unplanned) fail over. That will require that the primary VM is off and then replica will start the VM on the second host. The downtime will come down to how fast your VMs boot and shutdown. That's how my 2 hosts are configured.

Downtime is around 30 seconds.

Hyper-V has come a long way in 2012/R2 and is a solid piece of software definitely worth consideration, but not for a single server for a home.

Hyper-V comes in two flavours.
1. Free version (No limitations, only Server Core more or less requiring a domain to manage easily)
2. Installed as a role on Server 2012/R2. I wouldn't bother with Hyper-V on 2008R2. This will require a license for Windows Server which isn't free.

So keep in mind that Hyper-V free doesn't come with a GUI and it needs to be remotely managed. You have Powershell on the host of course (or remotely).

I'm currently running two Hyper-V hosts setup with replication. ALl the servers running on it are running Ubuntu Server with the only Windows VMs being the domain controllers and a media center.

Then as a final note, before i goto bed you could consider setting up a hyper-v cluster which i believe is free and doesn't require SCVMM. I'm pretty sure you can setup HA with shared storage that supports SMB 3.0 i believe.

 

[imagoon]

There's no hardware limitations anymore, but there's no high availability features in ESXi free either - at the very least I need vMotion so that I can actually shut down or reboot one of my C1100s without taking down my entire network.

You are not getting that for free then sorry. Hyper-V is going to start at around $700 per server to start getting to that level. The management portion (kinda like vCenter in ESXi) is around $3500-4000. vMotion is an essentials+ line and above which tends to start ~$5000 for three hosts and vCenter.

This ignores the requirements to fast vMotion / Hyper-V migration (shared nothing excluded here.)

 

[smakme7757]

You are not getting that for free then sorry. Hyper-V is going to start at around $700 per server to start getting to that level. The management portion (kinda like vCenter in ESXi) is around $3500-4000. vMotion is an essentials+ line and above which tends to start ~$5000 for three hosts and vCenter.

This ignores the requirements to fast vMotion / Hyper-V migration (shared nothing excluded here.)

He could use Hyper-V replica, but he would need a domain for that and it's not HA. But it will keep his downtime to a minimum.
As I mentioned above I'm pretty sure Fail Over clustering in Hyper-V is in the free version. Again it would require a Domain and shared storage.

 

[Lifted]

If you want live migratation between servers for free I think you'll have to look at KVM. OpenVZ supports this as well but is more suited for hosting environments.

 

[Asphodelus]

Edit: Saw you wanted HA. In that case you need shared storage if you want 0 downtime.

However Hyper-V replica would most likely give you what you need, but it isn't HA. You replicate your VMs from the primary server to the second server. So it's like a mirror. Then if you need to do maintenence on one of the hosts you just initiate a planned (or unplanned) fail over. That will require that the primary VM is off and then replica will start the VM on the second host. The downtime will come down to how fast your VMs boot and shutdown. That's how my 2 hosts are configured.

Downtime is around 30 seconds.

Hyper-V has come a long way in 2012/R2 and is a solid piece of software definitely worth consideration, but not for a single server for a home.

Hyper-V comes in two flavours.
1. Free version (No limitations, only Server Core more or less requiring a domain to manage easily)
2. Installed as a role on Server 2012/R2. I wouldn't bother with Hyper-V on 2008R2. This will require a license for Windows Server which isn't free.

So keep in mind that Hyper-V free doesn't come with a GUI and it needs to be remotely managed. You have Powershell on the host of course (or remotely).

I'm currently running two Hyper-V hosts setup with replication. ALl the servers running on it are running Ubuntu Server with the only Windows VMs being the domain controllers and a media center.

Then as a final note, before i goto bed you could consider setting up a hyper-v cluster which i believe is free and doesn't require SCVMM. I'm pretty sure you can setup HA with shared storage that supports SMB 3.0 i believe.

You are not getting that for free then sorry. Hyper-V is going to start at around $700 per server to start getting to that level. The management portion (kinda like vCenter in ESXi) is around $3500-4000. vMotion is an essentials+ line and above which tends to start ~$5000 for three hosts and vCenter.

This ignores the requirements to fast vMotion / Hyper-V migration (shared nothing excluded here.)

I have an AD Domain Controller running on a 2008 R2 VM. I actually have several spare 2008 R2 licenses lying around that I could run Hyper-V with, but would like to take advantage of the new features introduced in 2012, which I don't have any licenses of at the moment.

My understanding - and please correct me if I'm wrong - is that all features of the full version's Hyper-V role, including live migration, are available in the standalone free edition - so long as you can provide all of the supporting infrastructure.

Also, doesn't 2012 introduce shared nothing live migration?

 

[crash331]

Also, doesn't 2012 introduce shared nothing live migration?

Yes, it does:

http://technet.microsoft.com/en-us/library/jj134199.aspx

 

[imagoon]

I have an AD Domain Controller running on a 2008 R2 VM. I actually have several spare 2008 R2 licenses lying around that I could run Hyper-V with, but would like to take advantage of the new features introduced in 2012, which I don't have any licenses of at the moment.

My understanding - and please correct me if I'm wrong - is that all features of the full version's Hyper-V role, including live migration, are available in the standalone free edition - so long as you can provide all of the supporting infrastructure.

Also, doesn't 2012 introduce shared nothing live migration?

The point is, with out the management add on, most of that advanced stuff is multistep powershell on Hyper-V. Shared nothing is good in concept but is generally pretty easy to make more expensive than shared storage. Shared nothing means the disk has to be copied from one resource to another to migrate. This means the migration has disk transfer times to worry about. Not huge on a 40gig machine where you can move in 30-60 minutes but a larger VM with 500GB - 1TB of data can take the better part of a day to move and then you still need double the resources around just for the migrations, which mostly sits idle unless you enjoy migrating VMs repeatedly. Shared nothing also tends to wreck performance on any VM sharing the disk at the time of migration due to IO starvation. Also the busier the VM being migrated, the longer the move takes since disk changes are queued. We have set up in a lab a VM that would never finish moving using shared nothing because disk I/O was happening faster than it could move off the source server. Eventually the move aborted because the disk queue started to fill up the volume.

It has a place but "its cheaper" certainly isn't a bullet point once you get past the tiny "5 person office" world.

 

[PliotronX]

Neither. ESXi it it superior to both.

Architecturally and failover wise it's superior but I've developed a strong dislike for it. My team spent many a server class sessions troubleshooting why it won't detect NIC's or host optical drives (for the class we had to install not from PXE) rather than getting on to learning group policy. Whereas HyperV was literally "add HyperV role, add virtual machine" and we had virtual servers up and running. I can see why it is preferred in the real world over ESXi (at least at work I have yet to survey a server with it in use) not to mention it comes with Microsoft Server OS's and ESXi's license is the cost of another physical server.

 

[imagoon]

Architecturally and failover wise it's superior but I've developed a strong dislike for it. My team spent many a server class sessions troubleshooting why it won't detect NIC's or host optical drives (for the class we had to install not from PXE) rather than getting on to learning group policy. Whereas HyperV was literally "add HyperV role, add virtual machine" and we had virtual servers up and running. I can see why it is preferred in the real world over ESXi (at least at work I have yet to survey a server with it in use) not to mention it comes with Microsoft Server OS's and ESXi's license is the cost of another physical server.

Stick to the supported list and you wont have issues. Installing extra drivers is a single command installing the VIB via the command line or the vCenter server update manager so I am not really sure what your issue was unless you were using unsupported hardware. ESXi doesn't have anything called group policy, I assume you are talking windows at that point not sure.

I still to this day consider ESXi + vCenter light years easier to manage and use in the real world than any of the other products so far.

ESXi and Hyper-V's start up costs to get them apples to apples is about the same also. Without the system manager Hyper-V is a pain to manage. Same as ESXi without vCenter. You can use the CLI on both out of the box but the GUIs make day to day management easier.

 

[theevilsharpie]

I'm trying to decide between Hyper-V and Xen. Would anyone with experience with one (or both) like to weigh in with their thoughts on the pros and cons of each?

Hyper-V works fine, but is dependent on a domain environment for management. You can manage it outside of a domain, but it's a massive pain in the ass. This presents a problem if your DC is hosted within the Hyper-V environment, as you could run into a chicken-and-egg problem where Hyper-V can't start up properly because a DC isn't available, but you can't start the DC without Hyper-V being operational.

Xen has fallen out of favor in the open-source world, and is really only used anymore by big cloud providers that used it early on and don't see the need to change. Citrix provides an open-source package called XenServer that brings management of Xen more in line with what you'd expect from VMware or Microsoft, but Citrix has discontinued a bunch of their WIP addons for XenServer, and while they haven't come out and said it, I strongly suspect that Citrix has given up on the product and doesn't intend to develop it further. Functionality-wise, Citrix is largely competitive with ESXi and Hyper-V, but I've had stability problems with it and HA is a massive pain in the ass. However, it'll work well enough for home use.

VMware vSphere is nice, but outside of your budget.

KVM is also an option. Proxmox VE is a decent stand-alone KVM package, and is available for free. Proxmox VE also has HA functionality, although you'll have to provide for some type of fencing to avoid data corruption. If you prefer to run your own Linux distribution, libvirt is available, and VMM is also an option if you prefer a graphical interface (note that it's an X11 application). If you want a graphical web interface, take a look at oVirt. If you want to get really hardcore, take a look at OpenStack and its various services.

 

[Chiefcrowe]

I've read that the DC issue is fixed in the newest Hyper-V but i'm not 100% sure.

Hyper-V works fine, but is dependent on a domain environment for management. You can manage it outside of a domain, but it's a massive pain in the ass. This presents a problem if your DC is hosted within the Hyper-V environment, as you could run into a chicken-and-egg problem where Hyper-V can't start up properly because a DC isn't available, but you can't start the DC without Hyper-V being operational.

 

[PliotronX]

Stick to the supported list and you wont have issues. Installing extra drivers is a single command installing the VIB via the command line or the vCenter server update manager so I am not really sure what your issue was unless you were using unsupported hardware. ESXi doesn't have anything called group policy, I assume you are talking windows at that point not sure.

I still to this day consider ESXi + vCenter light years easier to manage and use in the real world than any of the other products so far.

ESXi and Hyper-V's start up costs to get them apples to apples is about the same also. Without the system manager Hyper-V is a pain to manage. Same as ESXi without vCenter. You can use the CLI on both out of the box but the GUIs make day to day management easier.

Sorry forgot to mention that I am at the mercy of whatever hardware is in these older PowerEdge servers for class. What is infuriating is that the same optical drive that was used for installing vSphere moments earlier is somehow not detected by vSphere's VM's. The host drive is selected, connected and active yet it never finds it to boot from. My team is next trying a 2008 R2 ISO on a thumb drive made with uNetbootin this evening but somehow by the way vSphere is not detecting the thumb drive it won't work so well either leaving us with PXE which our professor did not want us spending time setting up. I was not aware of vCenter, it sounds neat. I am a noob, just frustrated with the experience so far.

Hyper-V works fine, but is dependent on a domain environment for management. You can manage it outside of a domain, but it's a massive pain in the ass. This presents a problem if your DC is hosted within the Hyper-V environment, as you could run into a chicken-and-egg problem where Hyper-V can't start up properly because a DC isn't available, but you can't start the DC without Hyper-V being operational.

Interesting! I will have to bring this up with my professor today. Would a RODC be sufficient to prevent the problem?

 

[smakme7757]

Interesting! I will have to bring this up with my professor today. Would a RODC be sufficient to prevent the problem?

You use RSAT tools for Windows 7/8 to manage Hyper-V remotely. When one uses the free edition of Hyper-V you are using a "Core" install of Windows server where administration is done through Powershell or Cmd.

If you're Hyper-V host is having problems and your domain controller is on the same host then you won't be able to connect to the Hyper-V host remotely. Your only option is to log into the host locally and fix everything with Powershell.

The only other alternative is to use Hyper-V in a Workgroup, i tried it once and it drove me absolutely crazy. It's just so much more work. Both on the client and on the server.

Out of curiosity, what university are you attending? Sounds like a course I have taken?

 

[imagoon]

Sorry forgot to mention that I am at the mercy of whatever hardware is in these older PowerEdge servers for class. What is infuriating is that the same optical drive that was used for installing vSphere moments earlier is somehow not detected by vSphere's VM's. The host drive is selected, connected and active yet it never finds it to boot from. My team is next trying a 2008 R2 ISO on a thumb drive made with uNetbootin this evening but somehow by the way vSphere is not detecting the thumb drive it won't work so well either leaving us with PXE which our professor did not want us spending time setting up. I was not aware of vCenter, it sounds neat. I am a noob, just frustrated with the experience so far.


Interesting! I will have to bring this up with my professor today. Would a RODC be sufficient to prevent the problem?

Yeah the VMWare boot issue normally means you are emulating the CDRom in a way that the VM can't properly boot from. In nearly all cases you are better off booting the ISO by mounting it off a local datastore or using the vsphere tools to boot the VM from your laptop/desktop.

Example:

http://www.codero.com/knowledge-base/questions/262/__print

The fact that your professor is / was unaware of this would make me concerned about the quality of the instruction.

You also have to remember that hypervisors abstract the hardware from the VMs. Booting from a thumb drive is not typically a supported medium but does somewhat work in 5.1 and above.

 

[Lifted]

Sorry forgot to mention that I am at the mercy of whatever hardware is in these older PowerEdge servers for class. What is infuriating is that the same optical drive that was used for installing vSphere moments earlier is somehow not detected by vSphere's VM's. The host drive is selected, connected and active yet it never finds it to boot from. My team is next trying a 2008 R2 ISO on a thumb drive made with uNetbootin this evening but somehow by the way vSphere is not detecting the thumb drive it won't work so well either leaving us with PXE which our professor did not want us spending time setting up. I was not aware of vCenter, it sounds neat. I am a noob, just frustrated with the experience so far.

You'd save yourselves a lot of headaches if you upload an ISO to the datastore and select it under "Datastore ISO File" in the configuration of the CD/DVD drive for the VM. Don't forget to select "Connect at power on".