From the Blogosphere
Filling the Citrix Visibility Gap with an Application-Aware Network
Monitoring the end-user experience of applications
By: Sebastian Kruk
Jul. 4, 2013 05:00 PM
Citrix XenApp or XenDesktop is a perfect fit for lowering the costs of desktop management and simplifying access to the hosted applications from any device. Last week we discussed some challenges to application performance monitoring (APM) introduced by Citrix. Apart from getting yet another component in the data center to take care of, the virtualized application delivery becomes "black boxed" from the APM perspective. It gets harder to isolate the fault domain to the network, the infrastructure, or the applications themselves.
In the previous post we presented the case of The National Bank of San Borodin (NBSB -name changed for commercial reasons). The bank decided to expand its reach beyond the small island of San Borodin and render the access to its banking applications by its agents through Citrix XenApp. Ensuring good quality of service imposed additional challenges on the operations team. We analyzed how to discover and handle performance issues that can happen in the Citrix enabled environment in the last post. Today, we'll look into monitoring the end-user experience of applications delivered through Citrix.
Therefore it's indispensable to use an application-aware network performance monitoring (aaNPM) tool that can correlate end users to their interaction with applications virtualized with Citrix (see Figure 1).
Figure 1: Citrix-enabled architecture with an application-aware network performance monitoring (aaNPM) tool that is capable of analyzing the ICA protocol, understanding user sessions, seeing inside Citrix farm with Thin Client Analysis Module (TCAM) and monitoring the actual backend applications
The Operations team at NBSB used an aaNM tool to monitor the experience of the most active Citrix users (see Figure 2) and list each operation executed by the user (see Figure 3).
Figure 2: Checking the user experience of the most active users
Figure 3: Monitoring application performance through the actions of a single user
Monitoring Citrix Channel Consumption
Figure 4: Performance per Citrix channel shows that even with 25 users the Thinwire channel has much higher server realized bandwidth than other channels, e.g., Graphics that cannot deliver the same user experience even for only two users
The operations team used the aaNM reports to track bandwidth consumption and user experience across different Citrix channels (see Figure 4) and listed users using a selected channel (see Figure 5).
Figure 5: Listing users accessing one of Citrix channels
Applications Not Designed for Citrix
Figure 6: Exotic application (WebClient), not designed for Citrix, can consume resources that should be otherwise used by the main application (NBSB Access Exp)
The Operations team wanted to determine why the WebClient application affected other applications so much. They consulted the Operations report (see Figure 7) and saw that some users visited an online casino site frequently; that site happens to be a heavily interactive Web 2.0 service. The site transferred a lot of small files that affected the performance of other applications because Citrix could not leverage its delivery virtualization capabilities and had to transfer a lot of raw data across the network.
Figure 7: Accessing web applications via Citrix is not a good idea. Here some users were cannibalizing performance of key applications by playing online games
Performance Problems at the Client Side
Figure 8: TCP Zero Window problems reported by the aaNM tool
Last week we showed how to monitor network performance to ensure proper distribution of load over both Citrix servers and the backend servers.
In this post we illustrated that certain issues may only affect (or be caused by) some users at certain locations. The operations team at the National Bank of San Borodin required a holistic and in-depth end-to-end view of the whole application delivery to find the root cause of the problems. They achieved that by using Compuware APM Application-Aware Network Monitoring, a tool that enabled them to monitor not only the network, the infrastructure and the applications, but also analyze the end-user experience for degradation of the quality of service of applications and desktops delivered with Citrix XenApp/XenDesktop.
Reader Feedback: Page 1 of 1
Latest AJAXWorld RIA Stories
Subscribe to the World's Most Powerful Newsletters
Subscribe to Our Rss Feeds & Get Your SYS-CON News Live!
SYS-CON Featured Whitepapers
Most Read This Week