How To Properly Un-Present a LUN in ESXi 5

I have recently been working with a customer that was having an issue with ESXi 5, the problem was that the client unpresented a physical LUN to ESXi 5 by simply deleting the datastore and physically removing the LUN from the storage array software. That led to the condition knows as APD (All paths Down).

What happened is while the datastore was deleted, ESXi continued to try and access that device and since ESXi uses hostd to access devices and also uses hostd for ESXi to vCenter communications, that led to a slew of issues. In this blog, I want to focus on the correct way to delete and unpresent a LUN in ESXi 5. Here are the steps:

Posted by Elias Khnaser on 01/25/20122 comments

Three Ways of Looking at Mobility

It's interesting to discuss mobility with the different departments in an organization. They each define mobility differently and want to address it separately.

Talk to the networking team and all they want to talk about is wireless and how to enhance their wireless infrastructure and what features they can offer for a better user experience. For them, BYOD is a matter of enabling their users to use these devices on wi-fi securely and effectively.

Posted by Elias Khnaser on 01/23/20120 comments

Multi-Stream ICA for XenDesktop 5.5 & XenApp 6.5

In previous blog posts, I covered some new features of XenDesktop 5.5 and XenApp 6.5. I want to continue with that, and this time, let's look at the new QoS support via Mutli-stream ICA/HDX.

First, some background: The ICA packet today is comprised of multiple virtual channels that carry different types of data within them. For instance, each ICA packet could be carrying virtual channels of the following types: graphics, keyboard, mouse, audio, printing, clipboard, drive mappings etc. The challenge for QoS today is, if I want to classify ICA/HDX traffic from a network perspective, I would have to do the same for all the virtual channels inside of that ICA packet.

Posted by Elias Khnaser on 01/18/20122 comments

vSphere Tip: Processor Power Management Settings

I was meeting with a new customer right before the holidays and part of the conversation was that they were very unhappy with the performance of their blade system in a virtualized environment. They told me that they benchmarked the same workload on rack-mount servers versus blades and they saw the CPU Ready Time drop significantly using the rack-mounted servers. They asked if I I had seen that with other customers because, they were considering moving away from blades. This was a large customer with over 2,000 VMs in production.

Posted by Elias Khnaser on 01/09/20121 comments

7 Virtualization Predictions for 2012

As we bid farewell to 2011 and welcome 2012, I figured we would end this blogging year with a reading of the crystal ball "Eli style." It has been a great year and I have enjoyed all the comments and the responses that I have received from all of you on all the social media channels I am connected on. That being said, let's see if we can end this year with a bang of predictions:

Desktop Virtualization
I am sure you were expecting this one from me so I will keep it brief. In 2012, the adoption of desktop virtualization will continue to grow and enterprises will recognize that the effects of consumerization will force them at some point to start rolling out Windows 8 even as they've yet to complete or even start their migrations to Windows 7. Couple that with the expiration of Windows XP in 2014 and I think 2012 will be the year of the desktop.

Posted by Elias Khnaser on 12/29/20117 comments

How To: Add Multicore vCPUs in vSphere 4.1

With the release of VMware vSphere 5, VMware added GUI capabilities which allows you to tweak how many virtual CPUs and how many cores per virtual CPU each VM was configured with. This is a very useful tool because many times you come across operating systems and even applications that are limited in terms of the number of CPU sockets that they support, conversely, having the ability to add cores per virtual CPU socket increase performance quite a bit. This is a cool new GUI addition, but the technology exists in vSphere 4.1 as well, albeit not very apparent and requires manual configuration.

Posted by Elias Khnaser on 12/20/20114 comments

Cool Free Tool: SolarWinds Storage Response Time Monitor

Virtualization has changed the game as far as how we troubleshoot issues in our environment. It is no longer as simple to determine as it was before. Now that resources are shared, it is sometimes tricky -- is it a VM problem? Or is it the network? Or compute? Or all of the above?

That being said, at the heart of every virtualization infrastructure today is storage. Some have large, enterprise-shared storage of different sorts, while others have smaller ones, but we all have shared storage one way or another. Monitoring the latency between VMs and the storage that they're running on is crucial. SolarWinds for its part has released a really cool and free storage response time monitoring tool that plugs directly into your VMware infrastructure and reports back on virtual machines' IO.

Posted by Elias Khnaser on 12/15/20111 comments

Citrix XenApp 6.5 Instant App Access

One of the coolest features of Citrix XenApp 6.5 has got to be the new Instant App Access feature, what this does is dramatically reduce the amount of time it takes to launch published applications. So instead of the traditional login and wait for your profile to be created locally, settings to be applied, policies and so on, Instant App Access gives instant access to your applications -- as soon as you click on an application you are ready to use it.

Posted by Elias Khnaser on 12/12/20111 comments

Changing the World for the Better with Big Data, The Cloud

It's an exciting time to be in technology. As IT professionals, we get to say we are the generation that witnessed how Big Data transformed the world. we saw how virtualization revolutionized IT and gave birth to the cloud. But more importantly, we get to say that we are the generation that witnessed how technology helped us feed the world quicker, warm the world quicker, cure the world and maybe even heal the world.

You see, everything we do on a daily basis as IT professionals means something if we can put it in context. They say every action generates a reaction, an event could lead to a sequence of events or could have a trickle effect, but there is so much data out there, so much information and our brain can only process small nuggets, can only address information from a very narrow perspective.

Posted by Elias Khnaser on 12/05/201110 comments

ESX-to-ESXi Migration Key to Success? The ESX System Analyzer

As you plan your migration from ESX to ESXi, you should be pleased to learn about the ESX System Analyzer, a tool from VMware that helps you gather information about your ESX environment to ensure a successful transition to ESXi. As consultants, admins, engineers, our most valuable resource is information. Once we have all the information we need, we can design the best solutions, ESX System Analyzer collects the following information for your review, design and planning exercise.

Posted by Elias Khnaser on 12/01/20112 comments

Desktop Virtualization's Role in Mobile Device Management

Mobility is defined mainly by who you ask to define it. For instance, ask Citrix and mobility is all about apps, desktops and data on any device. Ask Cisco and mobility might be about wireless. If you ask other folks in the industry, you will learn that mobility is about mobile device management. Ask me and I say mobility is about all three of them combined and not separated as they fulfill a complimentary role to one another.

Desktop virtualization is definitely a building block when it comes to mobility. The influx of mobile devices from smartphones to tablets has invaded enterprises and users have demanded their applications, desktops and data to be accessible on these devices. Desktop virtualization directly addresses these concerns and enables the user access to applications, desktops and data on any device. Still, that is not the sole definition of mobility. How do we control these devices? How do we separate personal data from business data and how do we secure it, encrypt it, remotely wipe it? All these questions and more lead me into Mobile Device Management, aka MDM.

Posted by Elias Khnaser on 11/29/20116 comments

Release the Citrix Universal Print Server Now!

While browsing through the Citrix downloads section, I noticed that the Citrix Universal Print Server (UPS) snuck up on me, peeked its head out and said hello. Well, hello back! You are finally here? No, not yet, I am still a technology preview. Darn it.

So what the heck is the Universal Print Server? UPS brings the Universal Print Driver's Enhance Metafile format functionality to network print servers. (In English, Eli, English, you might be saying...)

Posted by Elias Khnaser on 11/17/20111 comments