Tuesday, October 30, 2012

vDisk + CIFS + ONTAP = :-)

Hi Everybody,

Something I'd really like to share.  In ONTAP 8.1.1 for 7 and Cluster-Mode we now support SMB 2.1!  For PVS folks this is huge news because we can put our vDisk images on CIFS shares now.  We've been testing this and all I want to say is, where has this been all my life?!  No more block storage for vDisk!  I have nothing against block and think it's a great protocol, but this is sooooo easy.

If I've got multiple PVS servers, I no longer need multiple vDisk images and have to worry about updating all of them.  I only have to update one image!.  If you choose to store your vDisk on block, we've got a great procedure using our FlexClones so you only have to update one vDisk image.  I'll include the link later on.  This also eliminates the need for clustered filesystems to share out the vDisk image.  You can now use CIFS that's built right into the controller!  Remember to make sure you have a version of PVS that will support this.

Dan Allen has a great blog on this regarding why this works and does a much better job than I could do.  Take a look.

Here's the link to the article if you want to use FlexClones to clone out your vDisk on block storage.

All for now.

Monday, October 29, 2012

Virtualizing XenApp Using Citrix PVS or NetApp VSC

Hi Everyone,

This blog is WAAAAAAAAAY over due.  I had this paper published in January and here it is October.  The cool thing is it's still relevant.  Well, I think it is anyway....

A growing trend in the XenApp world is to virtualize your XenApp servers.  It's easier to manage, less hardware, and it melds very nicely with your current virtualized Citrix environment.  XenApp is a very flexible tool and allows you to do MANY things in MANY different ways.  In my paper I discuss launching an application from a Citrix streaming profile using a NetApp CIFS share to store the profile.
If you have plans to virtualize your XenApp servers, you'll probably want to use a product like Citrix PVS or NetApp Virtual Storage Console, VSC, because it will keep the images from changing.  Remember, you've got users connecting to these things and the last thing you want is for them to be different if they connect from one to another.  Some applications don't take very kindly to that.  What's even cooler is you have one master image and all of the other images are read only, this makes for really easy OS updates!

In the paper I chop up the storage to reflect 1/2 using PVS and 1/2 using VSC, in the real world, you would really only do one method.  I was just showing both methods to be thorough.  Both are great products, but today I'm going to focus on VSC.  If you'd like to try this architecture, you'll need vSphere for your hypervisor and VSC installed as a plugin. 

I know what you're thinking, "But Neil, I thought VSC clones were full read/write clones, how are they helpful here?"  Ah, good question!  It is true that the clones created by VSC are full clones, but I'm using the Redeploy feature available to keep things in sync.  If you haven't tried Redeploy yet, it's a very cool feature.  Clones created from a parent can be redeployed from that parent and will retain their MAC addresses so when they come back your applications won't freak.  The product works in conjunction with the Customization Specification tool built into vCenter. (Another very cool tool!)  This way machines will be given their unique names and set everything correctly in Active Directory.  When the servers come out of the redeploy, they have any new patches or OS changes from the parent and will be ready to stream out your XenApp application.

There's so much more I could tell you, but I wanted to share the NetApp VSC and Redeploy capability in this architecture.  If you've got any questions or comments, please feel free to write one!

Thanks for your time.


Thursday, October 25, 2012

Why Enterprise Storage for Writecache?

Hi Everyone,

I'm often asked, "Why should I put my writecache on your storage?  It's only transient data."  While I was somewhere over the Atlantic I had a thought (yes, yes, occasionally I do get them.) regarding RPO and RTO.  For those of you who don't know, these are terms used in disaster recover and backup recovery.  RPO is the Recovery Point Objective and RTO is Recovery Time Objective.  Basically, how fast and at what point in your data do you want to recover from.  So what does any of this have to do with the writecache?  Good question!

Our best practice states you should put the writecache on disk so you don't overwhelm your PVS server and for lots of other good reasons.  Yeah, yeah, I know there will be tons of people saying, "Just put the writecache on the server." but that just raises a whole new set of problems.  Even though that disk is just transient data, it's still an integral part of the OS, so I asked my performance engineer to try a test!  He had 100 desktops running LoginVSI and he pulled the writecache datastore.  Things were not pretty after that.  The desktops hung and were even grayed out in vCenter.  vCenter still functioned, but it was slow and clearly did not like we had just done.

So imagine your writecache is on a less expensive storage that has no fault tolerance.  Will user data be lost?  Probably not, but your users will be stuck until you can get something online again.  Hence RTO.  We're always so concerened about protecting data, that I think we forget about protecting the infrastructure too.  Think of this as the public transit of VDI.  Writecache won't make you the new super start up, but it will get you to work so you can focus on becoming that super start up.

Hey, for more information on NetApp and PVS take a look here:
NetApp and PVS

Its a great paper written by Rachel Zhu and myself.

Wednesday, October 24, 2012

Hello World

Hi and welcome to my Blog.  My name is Neil Glick and I'm a Virtualization Architect for NetApp.  I focus primarily on storage and Citrix technologies, but from time to time I'll throw in some other things.  I hope you enjoy!

I just got back from Citrix Synergy in Barcelona.  Here's a picture of me and our Flexpod.  Don't we look great together?  The event was great, but I got a cold.

While there I taught a course with Citrix and Cisco with my mentor Rachel Zhu.  Our portion of the class focused on Virtual Storage Console for XenServer, NetApp System Manager and OnCommand Insight Balance.

VSC for XenServer is a free **(Edit 02/07/2013 - Regarding VSC for both VMware and XenServer - They are free to download, but do require specific licenses for some features.)**  XenServer plugin created by NetApp to enable provisioning of storage, creation of virtual machines and much more from within XenServer!  please see this link for more information:
VSC for XenServer

OnCommand Insight Balance is an awesome reporting application from NetApp that can help zero in on your virtualization environment and find problems before they become problems!  Here's a YouTube video I did with Mike Laverick.

That's all for now!