Citrix Diagnostic Facility (CDF) & PVS 7

Many of us, logging geeks, are used to debugging problems in our infrastructure by looking at historical logs (which most every application nowadays has) to pinpoint these issues. Why? Because generally logs never lie. And people do.

If you deploy or manage a Citrix environment, you are also well aware by now how important logs are for troubleshooting regardless if you do it yourself or you call Citrix Support. In PVS 5.x and 6.x, if logging is enabled, you would normally see the following logs under C:\ProgramData\Citrix\Provisioning Services\Logs:

LogsPicture

Each log corresponded to a process. For instance, if you are troubleshooting an issue with the Console GUI you would be looking at Console.log, the stream process would log to StreamProcess.log, etc. In PVS 7.x, however, server-side historical logging is no longer enabled through PVS nor it’s located under the same directory. Our modules are now integrated in Citrix Diagnostic Facility (or CDF) much like XenApp, XenDesktop and Citrix Receiver/ICA Client. There are two options that you can use to generate and collect a single CDF trace from PVS:

1. CDF Control (download it from CTX111961)

This tool is nice and easy. All you need to do is download it on your PVS server, extract it, run it as an Administrator, and start a trace (preferably select all modules). This works great if your issue is reproducible at will (for example, a MAPI error when launching the PVS Console). The trace is generated as a .ETL file in the same folder you installed CDF Control and can be viewed from the same tool or parsed to a .CSV file to open in a more convenient program such as Excel.

2. CDF Monitor (download it from CTX129537)

This is a very, very powerful utility. A bit more complex to install but adds a real value to your environment. It runs as a Windows service and generates a circular CDF trace under C:\Windows\CDF Monitor. There is a config file that comes with it and for PVS there is an extra step to go to CTX138698 and download the PVS-specific config and place it in the CDF Monitor installation folder to replace the original one. Luckily, full instructions on how to deploy CDF Monitor are provided in the same article. I highly recommend this tool for capturing intermittent issues and root cause analysis of production outages.

Note: CDF tracing is only integrated with PVS 7.x. There are no CDF modules for previous versions. Target-side logging can still be enabled from the PVS Console and is logged into CDF. ConfigWizard and Console logs are still available under the old folder.

Enjoy the deep dive!

 

About That New Cache Type…

As many of you have noticed, PVS 7.1 has a brand new cache type called “Cache in Device RAM with Overflow on Hard Disk.” This new feature of PVS is designed to provide better performance by combining the light speed of RAM with the efficiency of hard disk storage and at the same time avoiding previous hurdles such as unexpected BSOD when using RAM cache due to the memory getting filled up. The new differencing format of the file (VHDX) also resolves the issue when caching to device HD where applications accessing printer drivers would randomly crash.

As some of you have noticed, however, target device performance has not increased dramatically in terms of speed. In fact, some folks out there with IOMeters have reported that IOPs have not improved at all with the new cache type. This is currently a known issue due to a problem turning on the RAM portion of the cache and I know for a fact that Citrix is working on fixing it in the next hotfix release for PVS 7.1. So stay excited!

Edit:

The RAM portion of the this cache type is fixed in CTX140338 which is a target device hotfix.