Another one of our presenters at Citrix TechEdge 2010 is Michael Rock. Michael is a member of the Escalation Team, with a focus towards XenDesktop. His roles include working technically complex mission critical or hot customer issues, developing and delivering training to other teams and engineers, and the development, design, and coding of new tools which aid in troubleshooting Citrix products. Prior to joining Citrix two years ago, he spent four years as an IT support specialist, working also in development and design, with organizations including Florida International University, University of Indiana Bloomington and MNB Technologies.


Michael Rock, Escalation Engineer

Michael gave us some insight into what’s new with XenDesktop, and the session he’ll be co-presenting with Karen Sciberras, also on the Escalation team, at Citrix TechEdge during Citrix Summit and Citrix Synergy 2010: Troubleshooting XenDesktop deployments.

Q. How has Troubleshooting XenDesktop Deployments improved and/or how are you able to troubleshoot an issue more quickly from a support perspective this year?
Michael: An understanding of the process involved has made the biggest difference for me, from the points of view of both general improvement and the ability to more quickly bring an issue to resolve. If you know how a product is supposed to work at an in-depth level, problems are much easier to identify.

The following CTX article is a good example of this:

CTX119736: Troubleshooting XenDesktop Service Startup Issues

This article provides in-depth knowledge as to the mechanics involved during the startup process of various XenDesktop related services – a must in my opinion. Another general example is the study of CDF trace messaging output, and the idea of scanning through and realizing what a good example of a particular set of events should look like. This allows you the ability to filter out errors and failures that may act as red-herrings and brings you much closer to pinning down the real problem. An in-depth understanding of how the product works along with CDF trace messaging, this has been my potion for success.

Q. What Troubleshooting XenDesktop Deployment tips will attendees learn at your session this year?
Michael: As part of the presentation Karen and I will do, I plan on giving a walkthrough of CDF Trace Messaging, detailing the involvement of the Citrix Desktop Service (WorkstationAgent.exe) on the VDA and the Citrix Desktop Delivery Controller Service (CdsController.exe) on the DDC, and their roles in the Desktop launch sequence (or registration sequence – still being decided). This will provide some of the in-depth knowledge I’m referring to in my previous statement. Launch and Registration are two of the main areas which tend to result in problems, whether due to environmental atmosphere or product deficiency.

Q. What’s the most interesting case you’ve worked on this past year? Why?
Michael: I had a case where the only indication of failure during the creation of a new XenDesktop Desktop Group, was the following generic error:
“A problem has been detected with the desktop group “<Group>”. This could be a database or Desktop Delivery service issue.
Please check the IMA database, connection and that all the services on the Desktop Delivery Controller are running correctly before re-running discovery.”Review of CDF Trace messaging, along with review of the code and an understanding of the context in which the issue occurred, brought me to a quick resolve. CDF displayed the following, where we see an uncaught exception.:===Begin Exception Dump===
System.NullReferenceException: Object reference not set to an instance of an object.
   at Citrix.CMI.PSE.PoolManagement.IdleData.get_DefaultTimeZone()
   at Citrix.CMI.PSE.PoolManagement.IdleData.get_TimeZone()
   at Citrix.CMI.PSE.PoolManagement.PoolProvider.ConfiguredBusinessHours()
   at Citrix.CMI.PSE.PoolManagement.PoolProvider.ConfigureIdlePoolDetails(GroupAssignmentBehavior assignmentBehaviour, IdlePoolDetails poolDetails)
   at Citrix.CMI.PSE.PoolManagement.PoolProvider.CommitConfiguration(String poolName, GroupAssignmentBehavior assignmentBehaviour, Boolean machinesChanged)
   at Citrix.CMI.PSE.PoolManagement.Pool.CommitConfiguration(GroupAssignmentBehavior assignmentBehaviour, Boolean machinesChanged)
   at Citrix.CMI.PSE.Cmo.App.AppDataModel.CommitMemento(Boolean rollingBack)
===End Exception Dump===

Further review brought resolution to a Microsoft time zone related Hot Fix:
KB970653 August 2009 cumulative time zone update for Microsoft Windows operating systems

The following CTX article was published as a result:

CTX123944: Error: A problem has been detected with the desktop group

This example is interesting because it provides a scenario where both the use of product knowledge and CDF tracing led to a quick identification and resolve of the issue. The relevance of CDF tracing can be seen clearly in the above output, while product knowledge came into play via my on-the-fly research of the Desktop Group creation process. Specifically the role of a time zones and a certain time zone validation check which is performed by looping through all available time zones in the registry of the DDC.

Q.When you’re not working how do you spend your free time?  
Michael: When I’m not working, I’m either working or practicing in the second thread of my multi-existence, I’m a classical pianist. Check out my site: www.michaelgrock.net. Amongst other things here, I’ve set up a nice flash presentation of some old competitions / performances.

More Technical Training – Hands on Learning Labs at Synergy
This year at Synergy (Wednesday, May 12 – Friday, May 14), the Hands on Learning Labsare free to all Summit and Synergy attendees!  This event has been expanded and enhanced. Now there are even more labs to choose from for technical training in XenDesktop, XenServer, XenApp and NetScaler. Citrix has increased capacity from 600 seats to 3,000 to give Synergy attendees the in-depth, IT training they need. Visit the Hands on Learning Labs page to learn more. 

Learn more about TechEdge 2010, www.citrix.com/techedge

TechEdge schedule and class descriptions

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Let Michael know any thoughts, questions or feedback you might have for his session.

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TechEdge Close-up – Interview with Dave Hawkins

TechEdge Close-up Interview with Jamie Baker

Join us at TechEdge 2010 – Troubleshooting Tools, Methodologies