Month: May 2015

Cluster Resource Pools – remember not to use them as folders!

So recently we came across a performance issue with a bunch of VM’s on one of our clusters. Turns out from doing so much digging that they all shared a common thread, they were part of the same resource pool. The net effect was the VM’s contained were being constrained for CPU over their non-resource pool counterparts(the reason for the sudden CPU spike was as a result of a dodgy AV update being rolled out across the VM’s).
Removal of the resource pool helped settle things down somewhat (+ removal of said DAT :)). Reminded me of a particular slide from the excellent VMworld session which discussed the vey subject (

resource distribution_2

As noted above in our environment we had 12 VM’s essentially competing for the same level of resources as a single VM in the root resource pool. This would only because an issue when resources started becoming scarce and the resource pool share values would kick in


Field tip: Lync 2013 sharing issue in Xenapp 6.5 environment? check this out

Environment: Xenapp 6.5 HRP05 published desktops – supporting 20000 users across 2 data centres.

Issue: Lync screen sharing failing between published desktop sessions between the 2 data centres – all ok within sessions that are occurring in the same data centre.

Come across this posting

And it pointed to a similar issue, spoke about endpoint agent and a different version of lync but I did update the image I was working on and removed the agent. So far it has been rock solid, tried now 10 different users in the EDC with both iFlex and QIC systems and 7/8 in the ADC with a mix of both and have been able to screenshare on every occasion.


So fix as per above URL

Add the lync.exe exclusion added to edgesight agent exclusion list


Ever need to view VSphere host utilization from a Windows guest VM? Here’s how

A while back got asked by one of the IT folks here if they could interrogate the current health of the host running the VM he was on. As it was a development environment thought maybe fair game. As it turns out it wasn’t too difficult to get the info.

From :

“Sending performance counters into PerfMon
You can integrate virtual machine performance counters for CPU and memory into PerfMon for Microsoft Windows guest operating systems. This feature makes detailed information about the physical host available to the guest operating system. An adversary could potentially use this information to inform further attacks on the host. By default this feature is disabled. Retain the following .vmx setting to prevent host information from being sent to the virtual machine:

tools.guestlib.enableHostInfo = “FALSE” This setting blocks some but not all metrics. If you set this property to FALSE, the following metrics are blocked:


Going with a 2 vNIC setup with your citrix provisioned VM’s ? remember to edit your ICA listener config

Last wk noticed terrible performance in a new xenapp 6.5 farm we built. Running the latest and greatest patch-wise (HRP05) and with Hotfix 19 for Citrix PVS 6.1 for our image target device software.
The 2 NIC setup was needed for a dedicated VLAN for the PVS Streaming traffic. Needless to say turns out the traffic for ICA was running on that line too, all by default of course. A quick edit of the
ICA Listener configuration to only listen the ICA traffic on the non ICA NIC and all was good with the world again 🙂

How to publish and access a RDS 2012 r2 session host from your iphone/ipad from Azure

Been busy on a few bits and bobs lately namely in the Azure arena. To do the above actually is v.straightforward thanks in no small part to a document that Microsoft recently released.

2nd guide:

The next part again is v.straightforward, to make accessible via your ipad/iphone

i) Download RDS client for ipad/iphone –
ii) Add Remote Resources

1. On the Connection Center screen, under Configuration tap Remote Resources.
2. In the Remote Resources window, enter information for the Remote Resource:
o URL: enter your cloud service URL from above
o User name: Enter your AD credentials from the work done above
o Password:
3. Tap Save. The remote resources will be displayed in the Connection Center.
4. Should see a desktop icon appear on your “Remote Desktops” app – eg Azure Desktop…
iii) Follow the on-screen prompts and should take you to it


Enabling HTML 5 Receiver in Xenapp 7.6 site environment



Enabling HTML 5 Receiver in Xenapp 7.6 site environment

Recently had a use case pop up for this for our environment which in fairness isn’t difficult as its chief advantage is it allows for the requirement of only a standard web browser to access XenDesktop / Xenapp published applications & desktops


Citrix Storefront 2.x

Latest versions use WebSockets, what’s useful about them is they support full-duplex communication using only a single TCP socket. Why that useful you say? It can optimize the network bandwidth usage, thus reducing the overhead needed in order to open multiple HTTP connections between your browser and the StoreFront server.


Relevant policy settings below, disabled by default