VMWare vs Hyper-V

MentholMoose

it_consultant wrote: »

Xen server is one of the best virtualization platforms out there. I did a competitive analysis for a company and recommended Xen based on a number of factors including cost and performance. I had the same hardware (HP Blades) and ran ESX and Xen side by side. In every measurable metric, including HA, Xen was better and easier to use then ESX.

A basic Citrix XenServer implementation is probably easier to implement since it doesn't need any dedicated Windows servers (just a client), whereas a basic setup of VMware vSphere requires a Windows server for vCenter and a database. If someone is ever trying to sell you XenServer, they will mention this over and over as a huge advantage. Unfortunately, it is only applicable in small environments with few hosts and very limited needs.

The ease of implementation advantage disappears once you go beyond the limited feature set of XenServer Advanced since most features in Enterprise or Platinum require Windows servers. For example if you want functionality in XenServer similar to DRS and/or DPM from vSphere, you use Workload Balancing, which installs on a Windows server and needs a database (so, the same requirements as vCenter). DRS has more features, too, for example it has affinity and anti-affinity rules (I especially miss these when working with XenServer).

Another thing you will need a server for is if you buy XenServer Advanced or above and actually want to license it. There is now a Linux-based virtual appliance available, but it only supports XenServer and you will still need the Windows version to license other products like XenApp or XenDesktop. So if you have multiple Citrix products, you could run multiple licensing servers, or just run one Windows server for licensing everything.

As for actual ease of use for day to day tasks, I think vSphere wins hands down. You can get mostly everything done from the vSphere Client, whereas the XenServer client (XenCenter) is extremely limited. Even the XenServer documentation mostly covers the CLI because that is where you get most things done. I am fine with using the CLI, but I still like the vSphere Client because it has some nice features. I especially like that the network configuration has a visual component. XenServer has nothing like this, and it could really use it due to the possible complexity of networking with virtualization.

As for which is better, I guess it will depend on the environment and the requirements. I work with a couple of XenServer environments and don't find it better at all. In general it is a solid product, but the feature set is really lacking. There are many features of vSphere that I miss when working with XenServer Enterprise, that also aren't in Platinum.

it_consultant wrote: »

If you purchase Xen they end up giving you licenses to Xen App either free or severely discounted provided the XenApp servers *I dont know how they planned on checking up on this* were running atop the Xen server platform.

Do you mean XenDesktop, or do you have a link explaining this? It sounds like you mean XenDesktop since if you buy XenDesktop Enterprise or Platinum you get (limited) XenApp and XenServer licenses as well. I'm not seeing any mention of free XenApp on the XenServer editions chart:
XenServer Editions
Here's the XenDesktop editions chart showing that you need Enterprise or better to get XenApp and XenServer:
XenDesktop Features and Editions

it_consultant

The xenapp licenses came as part of the quote if we wanted them. They are practically useless if you dont already have a terminal services or xen app infrastructure already in place.

Lets not confuse what we are talking about here, if you bought XenServer you got (what used to be called metaframe server) xenapp for almost free. You could buy that product standalone and run it on ESX, Hyper-V, or physical server which is what people did before there was virtualization.

Obviously you need to license and pay for XenServer, the cost comparison I did was roughly $30,000 for the licensing on Citrix compared to $75,000 for the comparable ESX product. I tested the HA on a cluster of blades which connected to a NetApp iSCSI SAN. Xen won hands down in speed an ease.

I will give you an example, how long does it take to set up an iSCSI volume in ESX? Its not hard but you do have to dive a couple of steps in, in Xen server there is a wizard, I tell them the IP of the NetApp and the username and password and it does it for me...including setting up the volume on the NetApp which ESX (at the time) could not do. Its hard to argue with both the price and the fact that it took considerably less time to set up HA on Xen.

Not everyone will have a NetApp SAN sitting around for testing, I was lucky to be able to run both systems at the same time in order to really see a side-by-side comparison. The results were eye opening.

I did all my testing based on Windows guest operating systems since that was what the company used.

virtualization.info | Benchmarks: ESX vs Hyper-V vs XenServer

MentholMoose

it_consultant wrote: »

I will give you an example, how long does it take to set up an iSCSI volume in ESX? Its not hard but you do have to dive a couple of steps in, in Xen server there is a wizard, I tell them the IP of the NetApp and the username and password and it does it for me...including setting up the volume on the NetApp which ESX (at the time) could not do. Its hard to argue with both the price and the fact that it took considerably less time to set up HA on Xen.

There may be a handful of things that are slightly easier in XenServer, I don't think I said otherwise. If you are just setting up a basic implementation with only HA on a NetApp, and no other features, then XenServer might be easier. Note that XenServer supports very few SANs like it does NetApp, and if you want to take full advantage of your SAN you need to set up a dedicated server running StorageLink.

So how much of a time saving are you talking about here? 10 minutes? Now try putting 100 VMs into production, then migrate them to another SAN. On XenServer you are looking at custom scripting (unless you want to babysit your XenCenter or CLI session for the whole time) and literally DAYS of downtime. On vSphere you can use Storage vMotion and move everything on a schedule LIVE, no downtime at all, with a few clicks.

Or what about backups? Tthe Citrix recommended way for backing up XenServer VMs is to use agents in each VM. If you want it to be done efficiently, you can spend money to buy a third party solution such as Alike, or write your own backup system using the API. By contrast, vSphere includes VCB, which integrates into a bunch of third party backup solutions, as well as VDR.

What if you want a particular administrator to be able to power on or off one particular VM? On XenServer, you can't, RBAC has no fine-grained control. It's a few clicks in vSphere. I can go on and on with similar limitations.

it_consultant

I have to call you on it, I have moved VMs in XenServer between hosts with no downtime as well - where do you base your conclusion that this isn't possible or requires special scripting? Xen supports Left Hand, NetApp, Dells, and EMC as I described above. Thats a lot of the big players. Its a fairly simple task to move from one SAN to another provided they are both set up.

I didn't go into backups since on both ESX and Xen we used snaps and SAN replication which worked fine for both products.

On ESX or VMWARE you can either clone machines with a answer file slipped into the machine (needed to generate a new GUID and automatically attach to the domain) or use a ghost image of the same. It took very little time on both platforms with edge going to Xen because guests tended to run faster under that hypervisor.

We also set up xendesktop and the competing vmware solution (I forget what its called) and similar to my previous experience Xen handily won. We tried VMWARE view to try and replace xenapp, it was a complete failure. That view version is a couple of revs back by now so I would have to test it again to be fair to ESX.

MentholMoose

I am talking about moving VDIs from one SR to another. If you buy a new SAN that supports replication with your existing SAN, then you can use that. That is not a function of XenServer. If you can't use SAN functionality to replicate LUNs, you have to use the Move VM function in XenCenter, or use the CLI, while the VM is powered off.

EDIT: Here's another problem I've seen. The servers in my existing pool have been discontinued, and I want to add more. No problem, right, I paid for XenServer Enterprise, which clearly says it supports Heterogeneous pools. Unfortunately it only supports a couple of generation of Intel CPUs, and no AMD at all: Citrix XenServer HCL This is not even close to vSphere.

Also, even if you have compatible CPUs, networking is another story. To use all of the NIC ports of every server, every server needs identical NIC port quantity and connectivity. So if your new servers have 12 NIC ports and your existing ones have 8, you won't be using those extra ports unless you upgrade all of your existing servers (if it's even possible). This is no problem in vSphere, you can mix and match NIC port counts and vary connectivity as you see fit.

MentholMoose

it_consultant wrote: »

Lets not confuse what we are talking about here, if you bought XenServer you got (what used to be called metaframe server) xenapp for almost free. You could buy that product standalone and run it on ESX, Hyper-V, or physical server which is what people did before there was virtualization.

If you don't have a link that explains this, I think you may be mistaken. If XenApp was included with certain XenServer editions, I think Citrix would at least put it on the XenServer Editions table. However, what you are describing is true if you are buying certain editions of XenDesktop rather than XenServer. With XenDesktop Enterprise and Platinum, you get XenApp and XenServer licenses that can be used only for XenDesktop. This is explained on the XenDesktop Features and Editions table:

Citrix Essentials for XenServer, when acquired as part of XenDesktop, can only be used to manage hosted desktops and Citrix-provided components included with your XenDesktop license, such as the Desktop Delivery Controller, license and Web servers, and XenApp servers. You cannot use the Essentials included with XenDesktop to host other server workloads, or servers used for XenApp purchased separately from XenDesktop.

it_consultant wrote: »

I will give you an example, how long does it take to set up an iSCSI volume in ESX? Its not hard but you do have to dive a couple of steps in, in Xen server there is a wizard, I tell them the IP of the NetApp and the username and password and it does it for me...including setting up the volume on the NetApp which ESX (at the time) could not do. Its hard to argue with both the price and the fact that it took considerably less time to set up HA on Xen.

Are you sure that you (or someone) didn't setup a StorageLink server? I am pretty sure that StorageLink is required for the functionality you are describing. After StorageLink is setup, on the New Storage wizard you will have some StorageLink specific options for creating SRs on NetApp and other supported SANs. Without StorageLink you only have the option to create SRs with standard protocols, i.e. NFS, iSCSI, and FC.

Once StorageLink is setup, it is quite easy to create and manage SRs and LUNs from what I've seen. However setting it up requires a dedicated server and some up front work that reduces the ease of implementation, and of course it does not support all SANs (indeed, that is why I'm not using it, as it doesn't support Sun SANs), though compatibility is improving. The HCL is here: Citrix StorageLink Gateway HCL

it_consultant wrote: »

We also set up xendesktop and the competing vmware solution (I forget what its called) and similar to my previous experience Xen handily won. We tried VMWARE view to try and replace xenapp, it was a complete failure. That view version is a couple of revs back by now so I would have to test it again to be fair to ESX.

The main competitor to XenDesktop is VMware View (previously called VMware VDI). They are both improving rapidly and have their pros and cons; here's a review, which I like since it goes into some depth and includes several VDI solutions: Netresults: Messaging platforms

VMware View is not meant to compete with most XenApp features so if you wanted what XenApp does then I don't doubt that View wouldn't be suitable. Likewise if you wanted to build a VDI environment, you would not even consider XenApp since that's not what it does. If you are comparing VDI with VMware View and published desktops with XenApp, which is better will depend on the environment. You may be thinking of VMware ThinApp which does application virtualization. It is an alternative to application streaming in XenApp, though with ThinApp you will need your own deployment mechanism. ThinApp is included with View Premier.

Another issue I thought was worth mentioning is support. The VMware support plans you get with your purchase of vSphere includes maintenance and support. You can call them (12/5 for basic support, or 24/7 for production) and get support with no fee. On the other hand, Citrix Subscription Advantage is maintenance only. If you need help, you either pay Citrix something like $350 per incident, or pay your VAR (I guess that's great if you're the VAR ). There are support plans but they are just prepaid incidents, and even as an education customer I was offered no discount (so the plan was $3500 per year for up to 10 incidents). Either way it can add up fast and should not be ignored.

Anyway, it's obvious that XenServer is working in your environment. It is a fine product as I have already said, but I am quite aware of the limitations. I'm happy to share my experience to hopefully help people get informed. If I'm wrong on anything I'd like to be corrected and hopefully learn something in the process.

it_consultant

Even with higher costs on the support end VMWARE was still more expensive by a wide margin. VMware is not cheap and the yearly renewals are similarly not cheap. I have clients looking at me wondering why for their SMB we put in ESX and they are getting charged a yearly maintenance fee that is the same as a brand new HP server. Even in huge datacenters I imagine that this cost would have to be considered. Nothing I have seen from VMware suggests that their product is actually worth double or triple the price of its competitors.

Xen does not advertise the xen app license fee reduction on their public site, when you go through a quote from a citrix partner they let you know its an option. It surprised the heck out of us because we had already paid citrix an arm and a leg plus one kidney for the xenapp licenses.