New VDI Project

[pcstru]

Moving forwards Downes and Seimman's concept of connectivism is probably the best framework from which to approach education if e-learning is to succeed.

 

Anyway how did we even get onto this topic?

 

If you want to talk about solutions for education you eventually have to ask what the problems actually are.

 

[ETA - oh AND the forum law of thread drift.]

Edited May 24, 2012 by pcstru

[gshaw]

Very interesting thread, VDI really does seem to split opinion (although granted a lot of the hype is coming from the vendors selling it!)

 

I've been watching it as a technology for about 3 years now and analysing when the point will arrive that it hits that sweet spot of price \ performance \ features that makes it the accepted choice in the same way server virtualisation is these days.

 

Problems I've seen thus far...

 

1) Until recently VDI = SAN = costly. I can't see the point of taking the cost of infrastructure you can buy in stages (desktops) then spending the same \ more to move it to a huge initial cost by putting it in the server room.

2) Number of disks... as with all of these virtualisation-esque solutions IOPS are king... doesn't give great VFM if you then have to stack 20 odd SAS 15k disks to get enough grunt to provision 30 desktops on demand. Yes there's kludges around "boot storms" but it's not ideal. Replacing (cheap) SATA local PC disks with (expensive) SAS 15ks seems a bit pointless... affordable SSDs for this will be when we see the big shift imo.

3) Video performance... getting better with HDX, PCoIP etc but still seemingly not 100%

4) Licensing... not so much of a problem if you have EES (and therefore Software Assurance)... then there's the cost of the VDI software itself

 

Possible benefits if VDI done right...

 

1) No "image creep"... every machine reprovisions every time so you never get issues with viruses, Windows Update etc

2) Easy updates... new version of Office? Install on the Gold image and it's done

3) Smaller desk footprint... I really like the look of the AXEL Zero Clients, certainly frees up some space

4) Remote access... I do like the idea of the exact desktop being able to be accessed from home as opposed to a "nearly the same" Terminal Server... saying that I think the "Windows on an iPad" idea rather gimmicky and not that much of a benefit in the real world

 

How can VDI get there?

 

1) Easily expandable, pay-as-you-grow model... VDI in a box with the grid architecture looks a much better choice... start with 2 servers and scale up... lower initial costs

2) Affordable server SSDs... one of those will take the place of 20 odd HDDs but the prices need to come down...

[glennda]

With regards to what @gshaw has outlined I'll go through the answers to the problems hes seen In my opinion.

 

Problems

1. - Needing a SAN - Not always the case but to do it properly a san in a must. can be done affordably using Open-E Makes San affordable from decent spec Hardware. I Installed on last week as a testbed here on a Dl380 G4 with 15K scsi drives and seems to be rock solid. i've specced a Dl180 G6 with SAS drives in for a client using 1Gb iSCSI. Cost is a lot less and you can get some good bang for your Bucks (with replication etc)

2. Disks - is done properly doesn't need huge amounts of storage so not loads of disks.

3. not quite 100% but getting there with graphics offloading to the client device

4. Licensing - this is always the major downpoint for people as the cost can be see as astronomical if not justified correctly.

[gshaw]

With regards to what @gshaw has outlined I'll go through the answers to the problems hes seen In my opinion.

 

Problems

1. - Needing a SAN - Not always the case but to do it properly a san in a must. can be done affordably using Open-E Makes San affordable from decent spec Hardware. I Installed on last week as a testbed here on a Dl380 G4 with 15K scsi drives and seems to be rock solid. i've specced a Dl180 G6 with SAS drives in for a client using 1Gb iSCSI. Cost is a lot less and you can get some good bang for your Bucks (with replication etc)

2. Disks - is done properly doesn't need huge amounts of storage so not loads of disks.

 

1) not with VDI in a box now it's a grid that uses DAS... always their main selling point. Even with your DL180 example that's still what, 4-5k? Add that to two decent spec servers and you're not far off 10k just to get started. That's the cost of 30 PCs before you've even put the software and thin clients in... ouch

 

2) the disks aren't for storage but for pure speed, I remember a presentation showing you need about 20-30 IOPS per VDI machine you deploy... a 15k SAS disk can only do 180 (if you're talking random reads \ writes) so to get 30 odd machines provisioning at once you suddenly need a fair few of them in there. At current prices "disks is cheap" doesn't apply anymore and that's where I see part of the problem from a cost perspective... not to mention the power used for them.

 

Of course 1 SSD is up in the thousands of IOPS so with those the problem goes away in an instant

Edited May 24, 2012 by gshaw

[glennda]

1) not with VDI in a box now it's a grid that uses DAS... always their main selling point. Even with your DL180 example that's still what, 4-5k? Add that to two decent spec servers and you're not far off 10k just to get started. That's the cost of 30 PCs before you've even put the software and thin clients in... ouch

 

2) the disks aren't for storage but for pure speed, I remember a presentation showing you need about 20-30 IOPS per VDI machine you deploy... a 15k SAS disk can only do 180 (if you're talking random reads \ writes) so to get 30 odd machines provisioning at once you suddenly need a fair few of them in there. At current prices "disks is cheap" doesn't apply anymore and that's where I see part of the problem from a cost perspective... not to mention the power used for them.

 

Of course 1 SSD is up in the thousands of IOPS so with those the problem goes away in an instant

 

Ah I wasn't talking about VDI in a box but VMware my bad - but in terms of a SAN an Open-E solution is very good value!

[gshaw]

Ah I wasn't talking about VDI in a box but VMware my bad - but in terms of a SAN an Open-E solution is very good value!

 

No worries, good to have views on both products and all the available options

 

Btw does your DL180 scream like a banshee the whole time it's on? Was really disappointed at how poor the fan control is on ours... HP didn't seem too bothered about providing a firmware fix for it at the time (mid 2011). Seems to be related to the PCI-e riser card but they give the same "we know, we don't care" response to everyone

Edited May 24, 2012 by gshaw

[Willott]

Ah I wasn't talking about VDI in a box but VMware my bad - but in terms of a SAN an Open-E solution is very good value!

 

In terms of SAN - Nexenta based is very good value, and can do all the funky SSD caching (stick in a couple of STEC ZeusRAM and STEC Zeus IOPS), dedupe, compression, thin provisioning, clones, snapshots etc. Backend storage can be on 7.2k RPM disks, and let (small number of very fast) SSDs give you the performance required with a non Oracle price tag. I think it's reducing the cost of the backend storage required for VDI that will help to start bringing it more as an option for larger deployment.

 

They've also just released something that would be targetted at the VDI in a box type environment - http://www.nexenta.com/corp/nexentavsa-for-view

Edited May 24, 2012 by Willott
correcting VSA for view

[ozydave]

I'm in Buckinghamshire

Does anyone have a full vdi setup that I can come and have a look at in action.

We just appioneted new Ict company for a new build. There whole project Is based on vdi. It's what they can make the most amount of money on!!!!! Again no one has spoken to staff, not even the head is ict

As some of the other posts I keep looking at vdi but yet to be fully convinced so a site visit would good if anyone can help.

[pcstru]

I'm in Buckinghamshire

Does anyone have a full vdi setup that I can come and have a look at in action.

 

There's @jamesfed's VID in a box demo day on 6th June. Possibly close enough?

[jamesfed]

There's @jamesfed's VID in a box demo day on 6th June. Possibly close enough?

 

Cheers for the mention - still have space here

[CyberNerd]

I've been looking at some of these problems, there are solutions depending upon your chosen provider

 

Problems I've seen thus far...

 

1) Until recently VDI = SAN = costly. I can't see the point of taking the cost of infrastructure you can buy in stages (desktops) then spending the same \ more to move it to a huge initial cost by putting it in the server room.

You can do VDI from local disks and keep the images in sync , for example with drbd. SAN is useful but you still get pretty good speeds locally

 

2) Number of disks... as with all of these virtualisation-esque solutions IOPS are king... doesn't give great VFM if you then have to stack 20 odd SAS 15k disks to get enough grunt to provision 30 desktops on demand. Yes there's kludges around "boot storms" but it's not ideal. Replacing (cheap) SATA local PC disks with (expensive) SAS 15ks seems a bit pointless... affordable SSDs for this will be when we see the big shift imo.

 

It's pretty simple to mount images into a tmpfs ramdisk and run them from ram. as you say a hybrid or SSD would be pretty quick too. Using a copy on write filesystem for the images mean all the clients use the same image and each individual virtual machine only grows by a small amount. 512MB should easily be enough for a win7 image.

 

3) Video performance... getting better with HDX, PCoIP etc but still seemingly not 100%

SPICE is revolutionary in terms of graphics performance, rendering is on the client. It is definitely worth a look

 

4) Licensing... not so much of a problem if you have EES (and therefore Software Assurance)... then there's the cost of the VDI software itself

 

Depends on the licensing model. If you don't want support you don't need to pay for licenses (im thinking kvm) the support and device management contracts typically scale well with number of devices. Even with a support contract VDI isn't any more expensive than traditional clients if you have the time to learn it all. The initial startup cost would even be lower than replacing a lot of desktops. Windows licensing will always be expensive though, I thought even with EES you needed a separate virtualisation license?

 

I'm approaching VDI more like an app (for apps) rather than a desktop in its own right - ie browser based with no 'desktop' as such.

Edited May 26, 2012 by CyberNerd

[Dave_O]

I'm in Buckinghamshire

Does anyone have a full vdi setup that I can come and have a look at in action.

We just appioneted new Ict company for a new build. There whole project Is based on vdi. It's what they can make the most amount of money on!!!!! Again no one has spoken to staff, not even the head is ict

As some of the other posts I keep looking at vdi but yet to be fully convinced so a site visit would good if anyone can help.

 

We've gone from 100 Wyse thin clients using VDI down to about 50 + 20 for staff use externally (total estate is 875 Pc/laptops so represents about 11%). Still got the ESX's and the storage running it. You are quite welcome to come and have a look (Rotherham). If by a full VDI setup you mean across the whole school then "Hell no!!

 

Couple of questions

 

a) Who appointed them?

b) Can it be stopped?

[ozydave]

Hi Dave_o

SLT and sponsers appointed so that cant be stopped. I done a big refit of server side if things 2 1/2 years ago, VMware and 6 server xenapp farm. A lot to throw away!

I cannot see the need to go full vdi and just want to put reasoned arguments on the table to SLT.

 

Would love to come up to Rotherham, not to far for me but think to far for SLT to let me go!!!!

Edited May 27, 2012 by ozydave