NetScaler VPX: Ready for Prime Time

Well NetScaler VPX is now GA, actually I’m a little late as it was announced last week.  If you recall, I touched on this subject a few weeks ago when harping on the importance of a true load balancing solution for high availability in a XenApp environment.  As a brief recap, the VPX line of NetScaler is a virtual appliance solution that gives you all of the functionality of the hardware based version but runs on top of a hypervisor, mainly XenServer at this point. 

But take heart VMware lovers, word on the street is NetScaler VPX will be released for vSphere by November of this year.  According to the NetScaler VPX site  a free Express Edition is available for download.  Upon further inspection of the license guide, link below, the Express edition allows unlimited use of the Standard Edition functionality at 1Mbps full-duplex throughput.

http://support.citrix.com/article/CTX122426 

While that isn’t exactly practical for full production use, it does allow you to adopt and gain experience with this technology in your environment without being confined to an evaluation period.  The Express Edition binaries can be downloaded from the following link:

https://www.citrix.com/English/ss/downloads/details.asp?downloadId=1857216

Once your ready to move it to production you have a few choices regarding full purchased versions.  The following is a breakdown of the different VPX appliance flavors along with retail pricing:

	VPX 1000	VPX 200	VPX 10
HTTP Throughput	1 Gbps	200 Mbps	10 Mbps
New SSL requests/second	500	500	500
SSL Encrypted Throughput	1 Gbps	200 Mbps	10 Mbps
HTTP Compression Throughput	750 Mbps	200 Mbps	10 Mbps

VPX 1000 Standard = $15K

VPX 200 Standard = $5K

VPX 10 Standard = $1,200

The Standard edition gets you all the critical functionality around load balancing, short of GSLB which I’m not happy about, and Access Gateway Enterprise edition.  There are also Enterprise and Platinum editions of the appliances, an outline of the features can be accessed here:

http://www.citrix.com/%2Fsite%2Fresources%2Fdynamic%2Fsalesdocs%2FDataSheet_NetScaler_Sept09.pdf

Once you’ve decided which version you will be implementing you can use the following guide to get started:

http://support.citrix.com/servlet/KbServlet/download/20331-102-577426/NS-VPXGettingStarted-Guide.pdf

XenApp 5.0 FR2: Automated Management

A classic stereotype for Citrix XenApp as a technology, in about any IT organization, is that it requires a lot of effort to manage.  This especially holds true in larger environments with a lot of concurrent users, therefore usually translating to a number of servers to maintain. 

While there are a lot of creative ways to add efficiencies into the management of XenApp environments, Citrix as taken the next step in building these technologies right into the product.  With the release of XenApp 5.0 FR2, several features have been integrated to add automation with provisioning, power and capacity utilization, as well as general management tasks such as allowing business units to add users to published resources.  The post listed  below by Vinny Sosa from Citrix outlines all of these critical new features as well as other interesting benefits of 5.0 FR2:

http://community.citrix.com/display/ocb/2009/09/16/What%27s+new+in+XenApp+5+Feature+Pack+2+in+plain+English

Provisioning Server and XenServer Interoperability

While working on a XenDesktop POC this past week I encountered an issue with communication between Provisioning Server 5.1 and the target device client which promptly caused a wave of deja vue.  Could it be the old retry issue that has been around since PVS 4.5 and XenServer 4.1?

As insinuated above by the old product versions referenced, this has been a problem with virtualizing Provisioning Server target devices on XenServer since Citrix first comingled the 2 products.  Apparently depending on the configuration of the network card in the XenServer host a problem can occur with excessive retries on the target device side.  This translates to slow boot times when streaming a VM from Provisioning Server as well as long image capture times when trying to build a vDisk.  It appears to be caused by TCP Offload parameters being enabled on the physical adapter of the XenServer host.

A workaround for the issue is outlined in the following Citrix Knowledge Center article but basically you can set a registry key on the target device side which disables Offloading.

http://support.citrix.com/article/CTX117491

UPDATE: Greg Bulla, a friend of mine and tenured engineer at Old Dominion, shot me an email after reading this post to share some of his personal experiences on this subject.  Upon building a XenServer based guest and executing a capture for a vDisk, Greg encountered the timeout issue noted in my blog.  However, the fix I posted did not address his particular issue. 

After implementing the fix outlined in Citrix article CTX115658, he was able to correct the timeout problem with his VM.  This appears to be another method of disabling Large Send Offload.  The link for this particular article is listed below.  Thanks Greg!

http://support.citrix.com/article/CTX115658 

XenDesktop Design Resources

This one is going to be a short post as I just got home from the race track and I am wore out to say the least.  Tomorrow I will be starting a POC for a large educational institution in NC so I thought that I would share some of the resource which I find very in designing XenDesktop environments.  No matter if you are engaging with a consulting company, preferably us, or if you are going about it on your own, it is incredibly important to gain an understanding of the technology as well as best practice around configuration prior to starting an implementation.

http://support.citrix.com/article/CTX120760 - XenDesktop Design Handbook

http://support.citrix.com/article/CTX122044 - Migrating Users from Physical Workstations to XenDesktop

http://support.citrix.com/article/CTX121478 - Designing an Enterprise XenDesktop Solution

http://support.citrix.com/article/CTX120516 - Simplifying Application Delivery to the Virtual Desktop

http://support.citrix.com/article/CTX119775 - XenDesktop Scalability Analysis

http://jeremywaldrop.wordpress.com/2008/12/08/how-to-build-and-optimize-a-windows-xp-image-for-xendesktop/ - How to Build and Optimize a Windows XP Image for XenDesktop (Created by our very own Jeremy Waldrop)

Citrix XenApp Training, No Excuses!

It seems like all too many times I have witnessed people in the IT industry use training as an excuse not to learn something new…sounds backwards right?  Well basically, I think that people tend to get upset when their employers cut training or travel budgets  and use that as an excuse not to help themselves.  I think that a lot of us rely too much on structured training and do not leverage the resources readily available from an unlimited number of free sources.

A perfect example is located at the link below.  While browsing the Citrix Communities site I happened upon these great video tutorials which cover several technical topics around XenApp including profiles, Application Isolation and Streaming, CPU and Memory optimizations, XenApp policy, and the list goes on.  These are aspects which are often misunderstood, not properly utilized, and/or configured incorrectly in XenApp environments.  With just a little bit of time and initiative, leveraging resources such as this can make the aforementioned challenges simple to overcome.

http://www.citrix.com/English/ps2/products/subfeature.asp?contentID=164122

So take a few minutes out of your day to help yourself.  There is ultimately no excuse when it comes to bettering your skillset and your career.

Upgrading Provisioning Server vDisks: You’ve Got Options

I have been a huge fan of Provisioning Server ever since I started working with it when Citrix acquired Ardence a few years ago.  It is arguably indispensible in medium to large XenApp environments and provides the mechanism around efficient management of images for XenDesktop.  That being said I think a lot of organizations are turned off to using this technology based on the perception that it is overly complex.

Probably the 2 main reasons for this perceived complexity is the need for hardware commonality and the image upgrade process for specific items such as the PVS client, NIC driver, and certain other specific scenarios.  It is true that when streaming an image to bare metal the hardware needs to be relatively common, i.e. the same, across all systems consuming said image.  However, there are ways to layer in flexibility via a common image build process.  The second challenge around upgrading vDisk images has also recently been addressed with the release of Provisioning Server 5.1.

Prior to PVS 5.1 upgrading items in the image such as the PVS client or NIC drivers meant you had to lay your image back down to the  physical or virtual machine from which it was captured via  a reverse image process, upgrade the software or drivers, and then capture your image to a vDisk once again.  This process is time consuming especially if your a large environment and have many different vDisks.   Trevor Mansell, an engineer at Citrix, recently posted 2 great articles on how to leverage the new functionality called Direct VHD Boot in PVS 5.1 to enable the boot of even hardware based vDisk images on Hyper-V or XenServer eliminating the need for the reverse image process and recapture.

http://community.citrix.com/blogs/citrite/trevorm/2009/07/28/New+Way+to+Upgrade+with+PVS+5.1+and+HyperV

http://community.citrix.com/blogs/citrite/trevorm/2009/08/15/PVS+5.1+Direct+VHD+Boot+using+XenServer

This functionality adds a tremendous amount of efficiency to the vDisk upgrade process as well as many other benefits to XenDesktop environments, and physical and virtual environments where PVS is leveraged to centrally manage the delivery of operating systems.  Thanks to Trevor for this great information!

Citrix Port Number and Usage Explained

A customer recently expressed their frustration around not being able to find a document or resource that clearly outlines the network ports in use by the various Citrix products.  While most network engineers worth their salt can recite the ports used by ICA, there are a lot of other extraneous ports in use by not only the peripheral technologies around XenApp, but XenDesktop, Access Gateway, and a multitude of other products in the Citrix suite as well.

The document located at the first link below was created by the Citrix System III Interoperability Test Team of the Application Virtualization Group, say it 3 times fast, and covers the port usage and corresponding explanations for all of the major Citrix products.  I have also included an additional link which addresses XenDesktop specifically since only Desktop Server 1.0 is mentioned in the port usage document.

http://community.citrix.com/download/attachments/30311506/Citrix+Port+Number+Usage+and+Connections.pdf?version=1 - Citrix Port Number Usage and Connections

http://support.citrix.com/servlet/KbServlet/download/17436-102-18655/XD%20-%202.0%20-%20Pilot%20Reference%20Architecture.pdf - XenDesktop Pilot Reference Architecture

NetScaler VPX: HA for the Masses

Not too long ago Citrix announced the release of their NetScaler code in a virtual machine format.  While I’m a little late to the party concerning the announcement I don’t think many people have given justice to the importance of this addition to the Citrix product line.

The NetScaler software, yes I said software as that is where the magic lies, is truly the Swiss Army knife of network appliances.  Wait, did I just call it an appliance after calling it software?  Well yes, but it’s hard to compare it to anything else in the market place without placing in the context of hardware.  While the hardware aspect of the technology is important, ultimately it is just a vessel for the functionality rooted in the code.  That is precisely why the release of the VPX edition is so important.  (The purpose of this post is to focus on VPX but click here if you need a rundown on the general features and benefits of NetScaler).

But to understand the importance of this release you really have to break it down into a few aspects.  First, the ultimate downfall of a lot of Citrix environments resides directly with resource uptime or a lack thereof.  Companies who cannot afford a dedicated, hardware load balancer a lot of times rely upon manual intervention during a critical system outage or they use sub-par measures to ensure availability such as DNS Round Robin load balancing.  While these tactics are arguably better than nothing, they leave much to be desired and a lot of times give the system a bad reputation with users due to an interruption in service.

Even when an IT staff gets a hardware load balancer approved, the project can fall apart for a lack of support from the network team or vice versa.  I have seen it all too many times…when the true benefits of a technology such as NetScaler are not realized because the IT organization cannot decide who should manage the appliance.  The network team points the finger at the server group because the appliance has a ‘Citrix’ logo, and the server group states that it is a network appliance, etc, etc.

I feel that the VPX edition of NetScaler will work to change the adoption of dedicated load balancing in the server/application world and allow organizations to improve service delivery to the business as an ultimate result.  This acceleration of adoption will come from the fact that no specialized hardware will be required.  The appliance can be hosted as part of the virtual infrastructure facilitating faster integration and a reduction of cost in implementation.  This should hopefully also help to speed adoption by breaking down barriers between the different IT silos.

Of course the biggest, current caveat is the fact that it will only run on XenServer.  Citrix has made commitments that there are plans to allow for multi-hypervisor support.  To me this is goal #1 as if you have an ESX environment you remove the benefits of using it over the hardware edition due to the fact that at least a couple of physical servers would need to be allocated or purchased for the setup of a separate XenServer resource pool.  Once this is addressed I feel that VPX will be an extremely crucial and much more common addition to not only SBC/VDI environments, but IT resource delivery in general for all organizations.

More information as well as a link for downloading a tech preview can be found here:

http://community.citrix.com/blogs/citrite/craigel/2009/05/06/NetScaler+Virtual+Appliance

Wyse Virtual Desktop Accelerator (VDA): PCoIP Alternative?

Wyse recently announced the release of a software-only based solution for accelerating RDP and ICA traffic using both Wyse thin clients and standard workstations.  This is pretty exciting news as we all know that the user experience can often make or break a VDI/SBC deployment and anything that can make it better, specifically for remote users, is critical. 

With the software-based flavor of PC-over-IP on the horizon it is yet to be determined how the two will pair up, but Wyse currently claims that it can improve the performance of RDP and ICA connections by as much as 3x with 300ms latency and 768kbps downstream bandwidth.  This is pretty important for a few reasons.  First, it gives organizations that are not using VMware View an option for improving usability for their WAN-based users and second it extends the capabilities of existing environments who are in need of better performance.  Last, the solution does not require the purchase of specialized hardware on the server or client end to enable use which can typically hamper adoption of an alternative approach to deploying physical PC’s due to initial cost.

Wyse accomplishes this impressive boost in performance by designing their own custom transport protocol combined with a mixture of proxies, tunneling, and packet correction.  The following links contain more information about this exciting new technology as well as a download section for obtaining a trial version.

http://www.wyse.com/fulfillment/downloads/Wyse_Software.pdf

http://www.wyse.com/products/software/vda/

Performance Best Practices for vSphere 4.0

vSphere has been in the marketplace as a production release for about 2 months now and is becoming more prevalent across the install base of virtualization environments at a rapid pace.  This quick adoption is good for the community as a whole but can be challenging for the initial organizations that dive into this unchartered territory.

Part of reducing the amount of pain with a new version of a product or eliminating it altogether is thoroughly planning all aspects of the upgrade or new environment including the use of every piece of knowledge available.  The following document located on VMware’s site outlines the best practices for configuring a vSphere environment with performance specifically in mind.  Naturally as the rate of adoption accelerates industry knowledge and information will grow but this white paper is definitely a good start.

http://www.vmware.com/pdf/Perf_Best_Practices_vSphere4.0.pdf