28 Nov 2012
By Yendis

VMware VMFS: Technical Overview and Best Practices

VMware, , ,
The VMware Virtual Machine File System (VMFS) is a high performance cluster file system that allows virtualization to scale beyond the boundaries of a single system. This paper gives a technology overview of VMFS, including a discussion of features and their benefits. The paper highlights how VMFS capabilities enable greater scalability and decreased management overhead. It also provides best practices and architectural considerations for deployment of VMFS. Download http://www.vmware.com/files/pdf/vmfs-best-practices-wp.pdf Source: VMware
Read More
17 Nov 2012
By Yendis

Citrix Provisioning Services Console Timeout

Citrix,
Whilst modifying several objects in Provisioning services console the console took a long time and intermittently timed out with the following error:- Timeout expired.  The timeout period elapsed prior to completion of the operation or the server is not responding. The statement has been terminated. (more…)
Read More
17 Nov 2012
By Yendis

Citrix Xendesktop 4 with IE9 issues

Citrix, ,
I have recently come across an issue that became apparent when installing the latest VDA when IE9 is also installed. IE would completely freeze for no rhyme or reason or certain web sites with flash content would cause IE to become unresponsive.  After much analysis and late nights I have found that changing the following registry keys on the master image fixes the IE9 freezing/Unresponsive issues. Delete the following registry key HKEY_LOCAL_MACHINESoftwareCitrixCtxHookAppInit_DllsHDXMediaStreamForFlashiexplore Create the following registry key HKEY_LOCAL_MACHINESoftwareCitrixHDXMediaStreamForFlashServerPseudoserver Name: DisableInputSyncCallForSetObjectRects Type: REG_DWORD Data: 1 Since applying the above I have had no issues with IE9
Read More
12 Nov 2012
By Yendis

Storage performance – IOPS & Latency

Storage, ,
Storage I/O bottlenecks can have a big impact on virtual environments and can wreak havoc on the performance of the virtual machines within them. The guest operating systems and applications running inside VMs are constantly reading and writing to and from their virtual disks and anything that delays this can slow a VM to a crawl. Of all the resources a host manages, traditional storage devices are typically the slowest resource because they rely on mechanical spinning hard disks. In addition shared storage arrays are commonly used in virtual environments because of the many features that require shared storage and…
Read More
11 Nov 2012
By Yendis

Microsoft Windows 8 RT and Citrix remote access

Citrix, Microsoft, ,
Since the public release of Windows 8 RT people try to use Citrix remote access and fail.  The reason for that lies up on decisions made by Citrix.  Many companies have a Web Interface, Secure Gateway infrastructure and the reason why it doesn't work with Windows 8 RT. Requirements for Windows 8 RT Access Gateway Enterprise 10.x VPX (min) for remote access (Review the AG product simplification program for free upgrade http://bit.ly/VuhaAD) Citrix StoreFront 1.x StoreFront does NOT support Secure Gateway Receiver TechPreview from the store http://bit.ly/RsTKfm That means Web Interface and Secure Gateway needs to be replaced with StoreFront and…
Read More
11 Nov 2012
By Yendis

Web Interface replaced by Citrix Cloud Gateway

Citrix, ,
It's almost a year when StoreFront 1.1 was released. I posted a small comparison between StoreFront an Web Interface. Web Interface 5.4 is the last version an might get only security updates but EOL is 2015. Now this is a revisit of the list I posted but now for StoreFront 1.2 and Web Interface 5.4.   Since Web Interface is in "maintanance mode" no new features for WI, so just look at the bold changes at the StoreFront row. StoreFront got some unique features and addtions to match up with Web Interface. Still there are some things missing. My adivice: Start using StoreFront to…
Read More
04 Nov 2012
By Yendis

Citrix PVS and Antivirus exclusions

Citrix, ,
On a number of implementations that I've seen there is a lack of correct antivirus exclusions which can cause stability issues. Unfortunately it happens more often than one would expect and I have therefore decided to document the once that most people are missing. It should be noted that there are some different file names for various OS, and that some files doesn’t exist for some versions. I have tried to document everything as good as possible based upon some notes that I have taken over the years – however I still recommend that you review the recommendation below so they actually match…
Read More
02 Nov 2012
By Yendis

What is RAID?

Hardware,
I've had a number of emails asking me to provide details about RAID well here goes I think I've covered everything. RAID is a group of independent physical disks that provides high performance by increasing the number of drives used for saving and accessing data. A RAID disk subsystem improves I/O performance and data availability. The physical disk group appears to the host system either as a single storage unit or multiple logical units. Data throughput improves because several disks are accessed simultaneously. RAID systems also improve data storage availability and fault tolerance. Data loss caused by a physical disk failure…
Read More
24 Oct 2012
By Yendis

Broadcom 5719/5720 NICs using tg3 driver becomes unresponsive and stops traffic in vSphere

VMware, , ,
I have been experiencing on a number of occastions a loss of network connectivity on my VM server network.  After much analysis I have found in the errors logs excessive NetQueue messages similar to:- 2012-06-14T19:45:09.053Z cpu6:2092)<6>tg3 : vmnic3: RX NetQ allocated on 1 2012-06-14T19:45:09.053Z cpu6:2092)<6>tg3 : vmnic3: NetQ set RX Filter: 1 [00:50:56:6F:95:16 0] 2012-06-14T19:45:44.054Z cpu7:2092)<6>tg3 : vmnic3: NetQ remove RX filter: 1 2012-06-14T19:45:44.054Z cpu7:2092)<6>tg3 : vmnic3: Free NetQ RX Queue: 1 The performance enhancement from NetQueue does not benefit 1 Gb NICs.  This feature spreads the network load across multiple CPUs, and a single CPU can handle around 3 Gb of network load. (more…)
Read More
17 Oct 2012
By Yendis

Citrix license administration console password reset

Citrix,
I had an email today from a customer who had forgotten their admin password used for logging on to their license administration console.  Below is how you can reset the password. 1) Open the "server.xml" file located in the C:Program FilesCitrixLicensingLSconf directory 2) Find the entry that looks something like this: firstName="System" id="admin" lastName="Administrator" password="(ENC-01)UaFz17cJ2oNQ+LkskjkzUyVV5ZcmaoJCDCiuiusbB6zk2P0uR" passwordExpired="false" privileges="admin"/>; 3) Erase the contents between the double quotes after "password=" 4) Enter a plaintext password so it looks like this: password="test" 5) Change the passwordExpired value to be "true" 6) Save the server.xml file. 7) Restart the licensing services. 8) Close and re-open the…
Read More