My conclusions on VDI and other things

[Soulfish]

Yes I really have issues with "experts" never really found one that was. In any field. There are very few areas of IT (relevant to the school context) which, after a little time and effort cannot be fathomed. It would be great if the "experts" were paid on performance so rather than paying them £700 per day and end up with nothing, only pay when everything is working OK (or have definitely identified the problem). That would really help focus the mind.

I have to say that "experts" annoyed me greatly as well. I was told time and again that it would be impossible for us to get a working XenDesktop system setup and running on our own as it was simply too complicated that we needed the help of "experts". If anything it made us do things on our own, and as you've found Dave with a little time and effort anythings possible

 

Soulfish

 

I would love to come and see this in action (any day, any time), if nothing else, to restore my faith in VDI.

 

Dave O

 

I'd love for you to come visit - and the same goes for anyone else that's interested in VDI or how we do things here. I've got your PM so I'll drop you a line

 

Just to say I have seen Soulfish's network and his VDI and it impressed me, its certainly very quick to logon and shows no signs of being anything less than a standard PC for the end user.

 

Still have one or two bugs to iron out, but hopefully they should be gone as we move to the newly released XenDesktop 5 - which actually looks pretty easy to setup compared to XenDesktop 4!

[Abaddon]

We're running Xen Desktop with Wyse Zentihs here, on a VMWare hosted infrastructure. 250 desktops are available for use at any time, either on site, or remotely via our Citrix Portal. If anyone wants to come and have a look, they are welcome.

[Dave_O]

Soulfish

 

Nice to know there are other out there who feel the same as me. Yes the expectation of "experts" that schools IT support are not capable doing anything other than the most basic of tasks, is common. I has some jackass say "did I know that stored procedures are really quite complicated" and I should "leave them to the experts". Didn't have the heart to tell him I was an DB programmer for 8 years.

 

Always best setting things up yourself saves a lot of time and money and you learn so much. Also you know where the problems are and how to rectify them. VMWare, ESX, HBAs, Fibre and SAN were supposed to be really hard. Just follow the instructions and hey presto.

 

Where abouts are you?

 

Dave O

[ASJ]

Hi

 

I would like to add to this that we have a VDI solution in our school. Running XenDesktop, XenServer, Equalogic SAN and 3 fully populated Dell chassis. Originally we were using Chip PC thin clients but these were changed to Wyse TC's as their performance was better. The Gold image is XP SP3 (1ghz CPU and RAM) with Office 2007 installed. All other applications use AppV to stream them (this works very well). We also use AppSense to control the virtual environment.

 

There are normally 4/500 desktops in use at anyone time peaking to 700. There is also a CAG for external access.

 

Andrew

[GrumbleDook]

@AJ ... you know you have just volunteered to hold a meeting at your school. I'm sure some of the other Northants folk would be interested in seeing it. ;-)

 

ps ... are you doing BETT this year?

[ASJ]

Hi Tony

 

Will need to ask my bossman about that and off course he would want to get involved!!??!!

 

Not BETT this year - too much to do

Edited January 3, 2011 by ASJ
typos

[Axel]

Ian,

 

We have just further optimised ICA/Xenapp performance - if you download the latest f/w from our website you should see a noticeable increase in performance (again!)

 

Matthew

 

(Sorry - was meant to be a PM to Imiddleton as a response to post he left above - please ignore if not him - or not an Axel ICA user!)

Edited January 5, 2011 by Axel

[Duke]

Dave O - Just wanted to say I really appreciate you taking the time to write that original post. A lot of the things you've said reiterate what I've been trying to get across to management for a long time, so it's nice to hear it all from someone who's clearly 'been there'.

 

I don't 100% agree with all the VDI stuff you've said, but then I haven't deployed it myself, only played around with it. I did test one (nameless) thin client solution and was not at all impressed so I can 100% see where you're coming from. On the flip side I've tried the Sun/Oracle VDI stuff from Cutter that others have mentioned and I've been really impressed (especially when coupled with Sun SGD) so I still think it has potential as a solution.

 

Sounds like you've had a rough two and a half years, props for sticking with it.

 

Chris

[Butuz]

Fantastic post and thread. I've got more to say on the matter but have not got time!!

 

Butuz

[johnymac]

Thanks for this post, very interesting, have shared with the rest of the PT techs. Thanks again

[Dave_O]

VDI update

 

Time having passed from my original post I will, therefore, update you on our present position. The truth is nothing much has changed. The HyperV solution is working well. The refactored ESXs (IBM x3650s) are as solid as ever, the fibre attached SAN spins on. The advent of Windows 2008 R2 SP1 and VMM 2008 R2 SP1 have allowed the server count (mainly terminal servers) to go up, which I'm not sure is a good thing. DPM continues to back up effectively. Actually tested the DR routine with a machine I built on the HyperV and it worked there's a first. I can now officially say I'm impressed with HyperV. I would'nt use it on mission critical services but it has it's place.

 

Licensing with EES has made things a lot simpler. Took a while to squeeze the Sharepoint and Exchange forefront license keys out of Microsoft but we got there in the end. A year of stability has turned my attention from the backend platform to a much more worthwhile venture into documentation and VLE stuff. If I say so myself my ability to write IT related policy documents, strategic plans etc is awsome (OK its maybe just alright). The VLE/MLE/learning plaatform whatever they call it nowerdays is coming along nicely. I get a lot of stick about our "website" from the other techies in Rotherham, all I can say is that it will be up when we're good and ready.

 

I should probably start the VLE stuff on a different thread but hey.

 

Sharepoint 2010, Exchange 2010 fully integrated, Salamander Soft (Richard Wills) for site management, class site creation, SLK customisation, calendar integration, exposing SIMS data through bespoke webparts and general making stuff work. If you have read my other threads you will know my views on so called experts and consultants in the case of Richard W he actually is one! and a nice chap too. If you get the chance have a look at SalamanderSoft it does what it says on the tin.

 

The other members of my team are retro-gamers and have organised a week long event promoting the UK gaming industry. Speakers from the industry are coming in to help give students an idea of what is needed to get involved including coding, narrative and art work. Looks like it will be a good week. Have a look at Games Britannia

 

I'm rambling and going off topic now. Not sure I will be able to offers anything else to this topic but I hope my experiences will help you.

 

On that note, I was wondering if people would be interested in me doing a presentaion on this and other virtualisation topics, hosted at my school, half/full day, with a chance to have a look at all of our gubbins. Let me know what you think on this thread.

 

Dave O

Edited May 8, 2011 by Dave_O

[stephen1977]

@ Dave

 

What a refreshing and honest response from someone who made the same mistake as me. VDI is 'the way to go' as to speak. However, rushing into things and enabling a mindset that it will cater for everyone's needs is naive to say the least. Been there and done that. Trying to explain to teachers that they can no longer play DVD's very well was the first blow. Having to then justify to the geography department that they can no longer run Google Earth Pro on this new flashy and expensive system was the next. Ultimately it created more problems than it solved. Especially as regards to supporting the product once installed by the specialists. We all know the score here, being in IT, you are expected to become a master of citrix and Vmware overnight!

 

I'd suggest VDI is the way forward, but careful planning and training of support staff needs to come BEFORE its introduced to the network.

[Dave_O]

Reading back on some of the threads on VDI an old Edwin Starr song sprang to mind to mis-quote if I may "VDI, what is it good for? Absolutely nothing..."

 

OK. That's not strictly true, staff external access yes, in school via thin clients and old boxes... a waste of time, money and effort. Another year on and I do have to say that the thin clients have been no problem at all... when running Terminal services. VDI is still not there by any stretch of the imagination. VMWare were pretty cheesed off when I terminated my SnS just over a year ago. I did ask about new features etc in the coming year (they could not really quote anything major) and my decision has been vindicated, what have they given us since last year? 5.1 (I'm on 5.0) wow massive improvement.

 

As for virtualisation generally I have a couple of question

 

1) I don' t understand the arguments about stuff having to be physical. Why does SIMS have to be physical, DC physical etc? Is it performance? Do you really think in a school environment (we have 1450 students and 180 staff) that SIMS will be pushed to the absolute physical (excuse the pun) limit? I have sat and watched SIMS over many hours (years), IOPS, network, processor, memory and cannot figure out why it has to be physical? Please someone enlighten me!

 

2) Why do people think Virtual infrastructures are a bottleneck and try to scale them to be able to run the equivalent of NASA? I read on here that someone is suggesting using 10Gb connections? What the hell for!!? Now I've got 8Gb fibre which I have come to realise is actually stupid, I could have saved money and stayed with 4Gb. It never uses more than 1.5Gb even when running Veeam backups over fibre. If this is for networking rather than attached storage (iScSI) then this is even more insane. As an example, I normally have 4 x 1Gb NICs teamed for host connectivity so I disconnected 3 of these from each host and ran them with essentially just one NIC each for a week just to see what would happen and you know what? no difference. The HP switch monitoring software never registered above 60% on any of the NIC ports at any time even with 720 workstations accessing work at the beginning (read) and at the end (write).

 

Just in case I didn't make it clear at the beginning, forget VDI it's too expensive both for the kit and the licensing and just use terminal services, it does a good job within it's limitations. The important thing is knowing what these limitations are. Deploy in areas where these limitations will never be reached and you'll have happy staff and students.

[mrbios]

2) Why do people think Virtual infrastructures are a bottleneck and try to scale them to be able to run the equivalent of NASA? I read on here that someone is suggesting using 10Gb connections? What the hell for!!? Now I've got 8Gb fibre which I have come to realise is actually stupid, I could have saved money and stayed with 4Gb. It never uses more than 1.5Gb even when running Veeam backups over fibre. If this is for networking rather than attached storage (iScSI) then this is even more insane. As an example, I normally have 4 x 1Gb NICs teamed for host connectivity so I disconnected 3 of these from each host and ran them with essentially just one NIC each for a week just to see what would happen and you know what? no difference. The HP switch monitoring software never registered above 60% on any of the NIC ports at any time even with 720 workstations accessing work at the beginning (read) and at the end (write).

 

It's nice to find someone who shares my thoughts on this. Nothing to add really as you've pretty much covered my whole opinion on this, i get the feeling not enough monitoring and research go into a lot of the implementations/recommendations people give and receive.

 

The idea of "more is better" mentatlity is one that leads to schools throwing away a lot of money at unneeded equipment and configurations.

Edited March 3, 2013 by mrbios

[psydii]

This is a great thread. Thanks for sharing you critical review of your strategy, it has actually inspired me to step up to a challenge I can see coming at my place.

 

On over speccing your links. Your traffic summary is remarkably similar to mine, and I've got half the number of end user devices, a completely different architecture and and half of those are coming over a SINGLE 1GB/s link from the wireless controller. This similarity is suspicious. I wonder if the data collection timescales are smoothing out the peaks in our raw respective data sets?

 

You also say that reducing your bandwidth by a factor of 4 had no effect. Your only measure was traffic reported by the switches. How about client performance, log on time (under load), and UI responsiveness on the desktops?

 

My motivation for asking, I hope, is encapsulated in this anecdote: I once had (to my shame) all my server VM's running on one host for nearly a month. Once I realised and corrected it, I went back and looked at the data, we were trucking along at 70% CPU and RAM on the box and there was roughly the same traffic running out of one box as we had normally on two (4x 1GBe per host for iSCSI and network). When I made an off the cuff remark to one of the office team, only then did they say "well it has seemed a lot slower over the last few weeks than it was before". The trouble being that running at half capacity provided a 'just good enough' service, and the granularity of the monitoring system did not indicated that I was pushing the capacity limits of the links and CPU (oh yes for there was only one CPU running the whole server suite!).

[TheScarfedOne]

Just to jump onto this thread late...I'm running a terminal services farm for part of my estate, somewhere around 80/90 machines in curriculum and another 50 ish in admin locations. Works generally well, and bar some issues with some wyse units I would say its ok. We have a mix of wyse and windows thin PC units.

 

For your traditional graphics intensive areas, eg ICT, Art, Design, Music - physical machine is still the way... with over 300 machines lurking around the site.

 

On the other bits of the thread...I'm also a great advocate of Salamander; as well as being a Sharepoint, Exchange and Lync integrated user

Edited March 4, 2013 by TheScarfedOne

[Dave_O]

I wonder if the data collection timescales are smoothing out the peaks in our raw respective data sets?

 

You also say that reducing your bandwidth by a factor of 4 had no effect. Your only measure was traffic reported by the switches. How about client performance, log on time (under load), and UI responsiveness on the desktops?

 

 

1) No, sat and watched it most of one day (mid-week) had some peaks at around 80% (which is what you would expect) but that was it.

 

2) When I say no effect, that means everything, login time, internet speed (Smoothwall and TMG back end firewall both virtual) file access, Sharepoint and Exchange etc etc.

 

Bear in mind the rest of the virtual infrastructure was working fine, ESXs SAN etc, given that there are 3 hosts, the NIC load would have been across all 3 as different services (DC, Sharepoint, Exchange file services) would probably been spread across them (don't know for sure as I let VMWare deal with all that stuff ie vmotion, load balancing etc). I probably wouldn't advocate just 1Gb NIC but certainly no more than 2.

 

How come you were not alerted that one of the hosts was not functioning? As for CPU, one CPU in each host is plenty. See below for CPU usage

 

Edited March 3, 2013 by Dave_O

[Duke]

Reading back on some of the threads on VDI an old Edwin Starr song sprang to mind to mis-quote if I may "VDI, what is it good for? Absolutely nothing..."

 

[...]

 

Just in case I didn't make it clear at the beginning, forget VDI it's too expensive both for the kit and the licensing and just use terminal services, it does a good job within it's limitations. The important thing is knowing what these limitations are. Deploy in areas where these limitations will never be reached and you'll have happy staff and students.

 

I'm going to play devil's advocate for a bit... I've recently started working for a company that have done a lot of VDI installs, and I can honestly say there are 1000+ seat VDI deployments that are a huge success, and that thin clients work much better for them than fat clients did. It all depends on the scenario, the users' requirements, and what their expectations are. We've got sites where staff can walk up to a machine, plug in a smartcard, be logged on in 5 seconds, unplug the card and be logged off instantly, then go home, go to a website, and log back in to their session from home exactly where they left off. We've also got sites with machines spread out over a wide campus, and the staff on-site would struggle with managing them. With VDI everything's central, and on the very rare occasion a thin client does break, it can either be fixed from the central server or the hardware swapped out in a couple of minutes.

 

Is VDI suitable for everyone? No. VDI, if done properly, will lower your long term costs. Will it be cheaper in the short term? No, very unlikely. If you've got well-spec'd fat clients and are maxing out their CPU/RAM/GFX capabilities, then it's unlikely that thin clients will give you better performance. If you've got a site where the main use of PCs is Office, SIMS and browsing the internet, and they currently have very few or very old PCs, then VDI may offer a major improvement over what they've currently got. If you've got a new build and they need a huge number of PCs but can't afford to upgrade them every three years and need something that isn't going to get broken by users, VDI may be perfect.

 

 

As for virtualisation generally I have a couple of question

 

1) I don' t understand the arguments about stuff having to be physical. Why does SIMS have to be physical, DC physical etc? Is it performance? Do you really think in a school environment [...]

 

2) Why do people think Virtual infrastructures are a bottleneck and try to scale them to be able to run the equivalent of NASA? I read on here that someone is suggesting using 10Gb connections? What the hell for!!? [...]

 

 

1) Okay, using your first example of SIMS - I think most people say SIMS has to be physical is because for a long time Capita said they wouldn't support SIMS in a virtual environment, and no one wants their huge MIS system to be unsupported. Also, SIMS is largely just an SQL server, and SQL usually has fairly high disk I/O requirements (depends on how heavily you use SIMS). Disk I/O doesn't always virtualise very well, unless you have good local storage on your VMware/Hyper-V/whatever host (not recommended) or a good network link to your SAN with fast disks (expensive). Using your second example of a DC, it's more that you shouldn't have just virtual DCs, you should have at least one physical DC/DNS/DHCP server. The reason for this is simple - dependencies. Say everything goes down (long powercut or whatever) and your VMware/whatever host talks to the SAN via its hostname. You power up the VMware/whatever host, but it can't see the SAN because there's no server up doing DNS. You can't power up the virtual DC that does DNS, because to do that you need the host to see the storage. Same issue if something on the infrastructure side needs AD authentication for it to start up. You're stuck in a loop of dependencies that are very easily solved by having one physical DC. You can get around this by not having anything on your infrastructure that uses DHCP, hostnames (rather than IPs) or AD authentication, but most people just prefer to have a physical DC/DNS/DHCP server that they can power up first, and then start up their virtual hosts and storage.

 

2) Bottlenecks - Say I run 20 physical servers and they've all got 1Gb connections. Say they all peak at around 80%, and maybe half of them peak around the same time of day. If I virtualise all 20 of those servers and put them on one physical host with a 1Gb or 2Gb link, then at some point it's very likely I'll run into network bottlenecks that are (technically) due to the virtual infrastructure. I don't know anyone running 8Gb or 10Gb links, because in reality in a school very few of us are running that kind of network throughput. I do know people with blade chassis that have very high consolidation ratios and are coming close to maxing out 4Gb links though, and have a perfectly good reason to consider 10Gb networking.

 

That's my two pence anyway.

 

• VDI can be absolutely awesome if it's put in the right place. If someone's got high-powered fat clients and swaps them for thin clients expecting a performance increase, they're probably going to be disappointed. If they want a new, manageable, large array of desktops and don't need video editing capabilities (or similar), then VDI may be perfect for them.
  
• You keep some servers physical to either avoid loops of dependencies or single points of failure, or because you can't afford the hardware needed to give the required performance on a virtual server.
  
• You do 10Gb networking if you need it - most of us don't. If you're consolidating a lot of physical servers down onto one server by virtualising them, then you need to provide sufficient bandwidth for all of those servers. For some people that might only be 1Gb, for some people that might be 10Gb.
  

 

Like I said, just my opinion and just playing devil's advocate.

[psydii]

1) No, sat and watched it most of one day (mid-week) had some peaks at around 80% (which is what you would expect) but that was it.

Given your in depth self critical analysis, I think that you know this probably isn't really good enough to be sure. In the same way that I know there is no excuse for my not noticing all my VMs were running on one host. (It didn't trip any of the built in alerts, and we didn't look at the console for a month because it was just working and we were concentrating on other matters). Automated Monitoring and reporting is king for enabling good decisions to be made, or past decisions effectively reviewed.

 

In your environment do you have heavy Multimedia file transfers, or run with roaming profiles offline files and searchindexer enabled? For us these are where we see the maximum load on the network links.

 

2) When I say no effect, that means everything, login time, internet speed (Smoothwall and TMG back end firewall both virtual) file access, Sharepoint and Exchange etc etc.

 

Fair enough.

 

You appear to have 3x 12 Core 3Ghz Xeons. This is roughly equivalent 3x the grunt of my two hosts. Mine run at substantially over 50% during peak load. If I had two of those beasties of yours I would have the capacity to not need additional upgrades for another three years at least. However, by going cheaper than you I am already over capacity, and extremely limited in what I can do next without a third server.

 

In other news, I've got busy week. If I find the time I will tighten up my performance stats collectors and post an analysis to a new thread, for comparison.

[Dave_O]

In the same way that I know there is no excuse for my not noticing all my VMs were running on one host. (It didn't trip any of the built in alerts, and we didn't look at the console for a month because it was just working and we were concentrating on other matters). Automated Monitoring and reporting is king for enabling good decisions to be made, or past decisions effectively reviewed.

 

Damn straight! No excuse. You'll be first against the wall when the revolution comes!

 

In your environment do you have heavy Multimedia file transfers, or run with roaming profiles offline files and searchindexer enabled? For us these are where we see the maximum load on the network links.

 

Yes to multi media - make heavy use of a streaming media server, yes we use roaming profiles (kids profiles are fairly small we controll the desktop, staff profiles are large - they are crap at managing them, No to off line files, seachindexer? don't know.

 

 

In other news, I've got busy week. If I find the time I will tighten up my performance stats collectors and post an analysis to a new thread, for comparison.

 

As a starting point on performance, if you have a look at the thread below, I would be interested in your figures for SQI IO.

 

 

SIMS SQLOI

[Dave_O]

"I'm going to play devil's advocate for a bit.."

 

OK El Diablo bring it on.

 

A. I take it, from your initial paragraph, that you don't work in a school (any more?). Your comment " If you've got a site where the main use of PCs is Office, SIMS and browsing the internet, and they currently have very few or very old PCs, then VDI may offer a major improvement over what they've currently got."

 

Why not use terminal services!!! runs all of these perfectly at a fraction of the cost. At least give me a case where only VDI can be used.

 

1) "Okay, using your first example of SIMS - I think most people say SIMS has to be physical is because for a long time Capita said they wouldn't support SIMS in a virtual environment, and no one wants their huge MIS system to be unsupported. Also, SIMS is largely just an SQL server, and SQL usually has fairly high disk I/O requirements (depends on how heavily you use SIMS). Disk I/O doesn't always virtualise very well, unless you have good local storage on your VMware/Hyper-V/whatever host (not recommended) or a good network link to your SAN with fast disks (expensive)."

 

Not the case any more SIMS support virtual.

 

Seriously! This is a school and SIMS we are talking about not a ten thousand simutaneous user transactional database. At most we have 200 simultaneous user connections add to that remote calls for Sharepoint etc total no more than 300 (and that's being optomistic). Look at the disk activity and CPU (see below) this morning during peak time, not exactly stressing the system. Note the output of the SAN (V7000 below), given that it can achieve up to 50,000 IOPS not exactly having too push hard is it. Lets base the arguments on things that actually happen in schools not what someone thinks might be the case.

 

To that end, I would also be interested in anyones stats from the following thread

 

SIMS SQLOI

 

"Using your second example of a DC, it's more that you shouldn't have just virtual DCs, you should have at least one physical DC/DNS/DHCP server. The reason for this is simple - dependencies. Say everything goes down (long powercut or whatever) and your VMware/whatever host talks to the SAN via its hostname. You power up the VMware/whatever host, but it can't see the SAN because there's no server up doing DNS. You can't power up the virtual DC that does DNS, because to do that you need the host to see the storage. Same issue if something on the infrastructure side needs AD authentication for it to start up. You're stuck in a loop of dependencies that are very easily solved by having one physical DC. You can get around this by not having anything on your infrastructure that uses DHCP, hostnames (rather than IPs) or AD authentication, but most people just prefer to have a physical DC/DNS/DHCP server that they can power up first, and then start up their virtual hosts and storage."

 

Why would you have communication between SAN and host dependent on name resolution? That to me is a poor design decision. We had one or two power cuts early on and learnt this the hard way. Why is this a case for having a physical DC? With the advent of Server 2012 restoring a virtual DC is possible (no AD count number issues). We have the luxury of having a second virtual setup in a physically seperate location (another block) in which we host a third DC acts just like a physical one.

 

"2) Bottlenecks - Say I run 20 physical servers and they've all got 1Gb connections. Say they all peak at around 80%, and maybe half of them peak around the same time of day. If I virtualise all 20 of those servers and put them on one physical host with a 1Gb or 2Gb link, then at some point it's very likely I'll run into network bottlenecks that are (technically) due to the virtual infrastructure. I don't know anyone running 8Gb or 10Gb links, because in reality in a school very few of us are running that kind of network throughput. I do know people with blade chassis that have very high consolidation ratios and are coming close to maxing out 4Gb links though, and have a perfectly good reason to consider 10Gb networking."

 

The use of "say", "maybe" and "likely" do not fill me with confidence. You give a scenario which is similar to what we have (on average 25 VMs per host) difference is I am actually basing my comments on fact rather than supposition.

 

 

"VDI can be absolutely awesome if it's put in the right place."

 

So where is this place? Give me a use case that only VDI can fullfil?

 

"You keep some servers physical to either avoid loops of dependencies or single points of failure, or because you can't afford the hardware needed to give the required performance on a virtual server."

 

The only things you need physical are backup (even some of that can be virtual) and firewall. The rest...

 

"You do 10Gb networking if you need it - most of us don't. If you're consolidating a lot of physical servers down onto one server by virtualising them, then you need to provide sufficient bandwidth for all of those servers. For some people that might only be 1Gb, for some people that might be 10Gb."

 

10Gb please spare me! Perhaps if everybody is streaming video, music and large media files ALL of the time. Show me a place that needs 10Gb networking and I'll show you a network riddle with viruses and classes watching the latest Pixar movie.

 

[Duke]

Ok, not looking to get into an argument, just offering my observations.

 

Yes, up until very recently I used to work in a school. I now work for a company that does (amongst other things) big VDI deployments and we've had success with them for many years. I only say that to point out that VDI is out there and does work for people.

 

I'm a little confused over your argument of VDI vs Terminal Services, I see them as the same thing just using different protocols: Wikipedia - Desktop virtualization. Are you referring to "Terminal Services = Thin Clients pointed towards TS/RDS servers" vs "VDI = thin clients pointed towards a dedicated VDI provider like VMware View"? If so then we use both, depending on the customer's needs. Sometimes VDI with Terminal Servers is the best option, but I'd still call that VDI. Maybe I've misunderstood you?

 

Re SIMS - Yes, they do support it now, but not everyone may realise that which is why some people might still be wary. Also, not everyone can afford a SAN like yours, but do use SIMS really heavily. If your SQL server is running lots of things besides SIMS and you've got a decent SQL server already, why virtualise it on to storage hardware which may not be able to keep up if it's doing lots of other things? If you've got a good SAN or are using fast local storage and don't hammer SIMS, then I agree, virtualise it.

 

Re DC - Yep, in an ideal world nothing would depend on anything else and you could just power up the machines how you like. However, not everyone has an ideal set up like that, or maybe they're using hardware/software that at some level requires AD/DNS/DHCP and there's nothing they can do about it. Maybe they've still got other physical servers for other applications that can't be visualised, and they don't want to lose AD authentication if their virtual infrastructure goes down. If you can avoid that then great, but not everyone can, and so having the physical DC is useful to a lot of people.

 

Re Bottlenecks: It was a hypothetical scenario, thus the 'say', 'maybe' and 'likely'. No, that scenario probably won't apply to many schools, but I also don't know of any schools that have put 10Gb in either. Uni's supporting tens of thousands of users probably will find a use for 10Gb.

 

So where is this place? Give me a use case that only VDI can fullfil?

I think I'm confused over the differentiation between pure VDI vs VDI using Terminal Servers. To me they're both VDI, and which one I'd use would depend on the scale of the customer and what OS they're running. I don't think there's any case where VDI in general is the only solution, but I do believe there's ones where it's the best (it might be for speed, for manageability, for data security, for device security/vulnerability/damage, for long-term costs, etc.)

 

The only things you need physical are backup (even some of that can be virtual) and firewall. The rest...

If you have the luxury of not needing access to AD/DNS if your virtual infrastructure is down. Not everyone has that luxury, or the ability/budget to make it so.

 

10Gb please spare me! Perhaps if everybody is streaming video, music and large media files ALL of the time. Show me a place that needs 10Gb networking and I'll show you a network riddle with viruses and classes watching the latest Pixar movie.

Just because you don't need 10Gb, it doesn't mean no one does. I don't know of any schools that would require 10Gb, but like I said, I imagine the bigger unis probably do.

Edited March 4, 2013 by Duke

[Dave_O]

 

I'm a little confused over your argument of VDI vs Terminal Services, I see them as the same thing just using different protocols: Wikipedia - Desktop virtualization. Are you referring to "Terminal Services = Thin Clients pointed towards TS/RDS servers" vs "VDI = thin clients pointed towards a dedicated VDI provider like VMware View"? If so then we use both, depending on the customer's needs. Sometimes VDI with Terminal Servers is the best option, but I'd still call that VDI. Maybe I've misunderstood you?

 

Also

 

I think I'm confused over the differentiation between pure VDI vs VDI using Terminal Servers. To me they're both VDI, and which one I'd use would depend on the scale of the customer and what OS they're running. I don't think there's any case where VDI in general is the only solution, but I do believe there's ones where it's the best (it might be for speed, for manageability, for data security, for device security/vulnerability/damage, for long-term costs, etc.)

 

 

You've not misunderstood me, just what the difference is between VDI and terminal services. Using Wikipeida as a source, seriously!?? The fundamental difference is the level of isolation afforded by VDI over terminal services. Isolation of machine instances and applications.

 

Re SIMS - Yes, they do support it now, but not everyone may realise that which is why some people might still be wary. Also, not everyone can afford a SAN like yours, but do use SIMS really heavily. If your SQL server is running lots of things besides SIMS and you've got a decent SQL server already, why virtualise it on to storage hardware which may not be able to keep up if it's doing lots of other things? If you've got a good SAN or are using fast local storage and don't hammer SIMS, then I agree, virtualise it.

 

Not sure what point you are making here? Are you an advocate of physical? If so give me some evidence to support your argument, as I have supplied in my post.

 

If you have the luxury of not needing access to AD/DNS if your virtual infrastructure is down. Not everyone has that luxury, or the ability/budget to make it so.

 

?? This is not a luxury it's by design. If you mean having a secondary Virtual infrastructure then yes.

 

 

Re DC - Yep, in an ideal world nothing would depend on anything else and you could just power up the machines how you like. However, not everyone has an ideal set up like that, or maybe they're using hardware/software that at some level requires AD/DNS/DHCP and there's nothing they can do about it. Maybe they've still got other physical servers for other applications that can't be visualised, and they don't want to lose AD authentication if their virtual infrastructure goes down. If you can avoid that then great, but not everyone can, and so having the physical DC is useful to a lot of people.

 

Re Bottlenecks: It was a hypothetical scenario, thus the 'say', 'maybe' and 'likely'. No, that scenario probably won't apply to many schools, but I also don't know of any schools that have put 10Gb in either. Uni's supporting tens of thousands of users probably will find a use for 10Gb.

 

Just because you don't need 10Gb, it doesn't mean no one does. I don't know of any schools that would require 10Gb, but like I said, I imagine the bigger unis probably do.

 

These are schools we are talking about not universities, why quote an example that is, to all intents and purposes, outside the scope of this forum.

[Duke]

Ok, looks like we're not going to agree on any points here so I'll leave it. I was merely trying to make the point that although VDI clearly hasn't worked for you, and that you don't need a physical SIMS server, DC or 10Gb, those things aren't true for everyone.

[Structurplan]

Just to jump onto this thread late...I'm running a terminal services farm for part of my estate, somewhere around 80/90 machines in curriculum and another 50 ish in admin locations. Works generally well, and bar some issues with some wyse units I would say its ok. We have a mix of wyse and windows thin PC units.

 

For your traditional graphics intensive areas, eg ICT, Art, Design, Music - physical machine is still the way... with over 300 machines lurking around the site.

 

On the other bits of the thread...I'm also a great advocate of Salamander; as well as being a Sharepoint, Exchange and Microsoft Lync integrated user

 

Hey ScarfedOne,

do you have some examples?