Welcome to vSphere-land!

There are over 180 blogs dedicated to VMware virtualization, here’s your chance to pick your favorites and determine the top blogs. The last voting was over a year ago and new bloggers are springing up every month. When casting your votes please keep the following in mind about the blogs.

• Longevity - Anyone can start a blog but it requires dedication, time & effort to keep it going. Some bloggers start a blog only to have it fall to the wayside several months later. Things always come up in life but the good bloggers keep going regardless of what is happening in their life.
• Length - It’s easy to make a quick blog post without much content, nothing wrong with this as long as you have good content in the post that people will enjoy. But some bloggers post pretty long detailed posts which takes a lot of time and effort to produce. The tip of the hat goes to these guys that burn the midnight oil trying to get you some great detailed information.
• Frequency - Some bloggers post several times a week which provides readers with lots of content. This requires a lot of effort as bloggers have to come up with more content ideas to write about. Frequency ties into length, some do high frequency/low length, some do low frequency/high length, some do both. They’re all good and require a lot of time and effort on the bloggers part.
• Quality - It all comes down to whats in the blog post regardless of how often or how long the blog posts are. After reading a blog post if you come away with learning something that you did not previously know and it benefits you in some way then you know you are reading a quality post. Good quality is usually the result of original content, its easy to re-hash something previously published elsewhere, the good bloggers come up with unique content or put their own unique spin on popular topics.

So please take all this into account when casting your votes, here are some more details on the voting:

• You can pick 10 of your favorite blogs and also rank them in your order of preference after you pick your 10. The results will be weighted with #1 ranking getting 10 points and #10 rankings getting 1 point. Point totals will be tabulated and from them the top 50 will be determined.
• Blogs are listed on the ballot  in alphabetical order with the current top 25 blogs highlighted in bold & underlined text, so please go through the whole list when making your choices (Duncan ended up on the bottom).
• New this year we also having voting in special categories to help distinguish certain types of blogs. The choices of which blogs to include in the categories was the result of this survey and my best guessing. The categories are independent of the general voting so first pick and rank your top 10 overall favorite blogs and then choose your favorite blog in each category.
• Voting will run until 2/7, afterwards the results will be determined and announced on a special podcast with myself, Simon Seagrave, David Davis and John Troyer live at VMware Partner Exchange.
• Several random voters will be picked to win a copy of the Train Signal’s  new vSphere 5 and View 5 video training courses.
• Duplicate vote protect is enabled, we’ll be using geolocation, IP addresses & cookies to protect against duplicate votes. This isn’t Chicago, please be honest and fair when voting, any suspicious votes will be tossed.
• If you are not familiar with a blog you can use my vLaunchpad to see links to them all. Try not to pick blogs based just on names but also take content into account. There are a lot of good blogs currently not in the top 25 that deserve to be there.

So what are you waiting for, head on over to http://vote.vsphere-land.com to cast your ballot and reward the best bloggers for their hard work and dedication by letting them know that you appreciate them. In case you need it here’s the direct link to the survey as well.

Special thanks to Train Signal for sponsoring the voting!

This is my final post highlighting the white papers that I did for SolarWinds. This one focuses on a white paper titled “Capacity Planning in Virtual Environments” which is a topic that is often not very well understood or executed in virtual environments. Capacity planning can be a real challenge in virtual environments and there is a lot more to it than meets the eye, below is an excerpt from this white paper, you can register and read the full paper over at SolarWinds website.

Virtualization is all about the sharing of resources. You have to plan with the big picture in mind and take into account your virtual environment as a whole. A balance of resources is critical in a virtual environment since the server hardware used for virtualization is bigger and more expensive than traditional server hardware as it has to support many virtual machines (VMs) running on it. If resources are unbalanced on a host, it can lead to wasted resources, and since the whole point of virtualization is to make the most efficient use of all resources, this goes against the reasons that we virtualize in the first place. For example, if a host runs out of physical memory, it limits the number of VMs that can run on that host despite having plenty of other resources available to it. Sure, you can use memory over commitment, but performance severely degrades once your VMs start swapping to disk to make up for the lack of physical host memory. As a result, the lack of having enough physical memory available for VMs means that you are wasting resources and money.

Trying to keep your resources balanced isn’t all that simple; you need to look at historical resource trends and usage to determine what that balance point is. Trying to calculate this manually is almost impossible. You need tools that can analyze your historical data and report how your environment has grown over time, how it stands today and how it will look in the future. Another area that further complicates resource calculations is spare capacity. If you are using High Availability in your environment, which most companies do, you have to maintain sufficient spare capacity to handle the load when host failures occur. So, you need a pool of resources that is unused at all times so you have enough resource capacity to handle VMs from failed hosts. Trying to factor spare capacity into your resource calculations can quickly get complicated, having a tool that can do this for you can make it a much easier exercise.

Full paper available here…

Today I wanted to highlight another white paper that I wrote for SolarWinds that is titled “Storage I/O Bottlenecks in a Virtual Environment”. I enjoyed writing this one the most as it digs really deep into the technical aspects of storage I/O bottlenecks. This white paper covers topics such as the effects of storage I/O bottlenecks, common causes, how to identify them and how to solve them. Below is an excerpt from this white paper, you can register and read the full paper over at SolarWinds website.

There are several key statistics that should be monitored on your storage subsystem related to bottlenecks but perhaps the most important is latency. Disk latency is defined as the time it takes for the selected disk sector to be positioned under the drive head so it can be read or written to. Once a VM makes a read or write to its virtual disk that request must follow a path to make its way from the guest OS to the physical storage device. A bottleneck can occur at different points along that path, there are different statistics that can be used to help pinpoint where the bottleneck is occurring in the path. The below figure illustrates the path that data takes to get from the VM to the storage device.

The storage I/O goes through the operating system as it normally would and makes its way to the device driver for the virtual storage adapter. From there it goes through the Virtual Machine Monitor (VMM) of the hypervisor which emulates the virtual storage adapter that the guest sees. It travels through the VMkernel and through a series of queues before it gets to the device driver for the physical storage adapter that is in the host. For shared storage it continues out the host on the storage network and makes its way to its final destination which is the physical storage device. Total guest latency is measured at the point where the storage I/O enters the VMkernel up to the point where it arrives at the physical storage device.

The total guest latency (GAVG/cmd as it is referred to in the esxtop utility) is measured in milliseconds and consists of the combined values of kernel latency (KAVG/cmd) plus device latency (DAVG/cmd). The kernel latency includes all the time that I/O spends in the VMkernel before it exits to the destination storage device. Queue latency (QAVG/cmd) is a part of the kernel latency but also measured independently. The device latency is the total amount of time that I/O spends in the VMkernel physical driver code and the physical storage device. So when I/O leaves the VMkernel and goes to the storage device this is the amount of time that it takes to get there and return. A guest latency value that is too high is a pretty clear indication that you have a storage I/O bottleneck that can cause severe performance issues. Once total guest latency exceeds 20ms you will notice the performance of your VMs suffer, as it approaches 50ms your VMs will become unresponsive.

Full paper including information on the key statistics related to storage I/O bottlenecks available here…

Continuing from my post on Monday which covered the white paper that I did for SolarWinds on the top 5 management challenges with virtualized environments, I wanted to highlight another of the white papers that focuses on one of those specific management challenges. This white paper is titled “Performance Management in a Virtual Environment” and covers how performance management differs from traditional physical environments, how to get started with performance management and knowing where to look and how to interpret the many statistics that are unique to virtual environments. The white paper also includes a table that details 13 key statistics that you need to pay attention to in virtual environments. Below is an excerpt from the first paper, you can register and read the full paper over at SolarWinds website.

So you’ve implemented virtualization and don’t know where to start when it comes to monitoring the performance of your virtual environment. In a traditional non-virtual environment you monitor performance through the guest operating system which is installed directly on the server hardware. Typically a centralized monitoring system relies on an agent installed on the guest OS or built-in components like Windows WMI to read performance statistics from the server. With virtualization this type of performance monitoring is no longer effective; the reason is the guest operating system is no longer seeing the physical hardware of the host. Instead it is seeing virtual hardware that is emulated by the hypervisor so performance statistics that are measured inside the guest OS are not an accurate reflection of the physical hardware of the host. As a result you need a monitoring application that is aware of the virtualization layer and can also measure the statistics that are unique to virtual environments.

Virtualization built-in performance monitoring tools like VMware’s vCenter Server can provide raw performance statistics for the virtual environment but doesn’t help you interpret them. The information returned by vCenter Server can be overwhelming and knowing what to look for and what the numbers mean can be difficult. Additionally vCenter Server is designed to mainly monitor and report at the virtualization layer and doesn’t extend to far into the guest OS layer so it does not provide a complete monitoring solution. There are hundreds of performance statistics that are generated by ESX/ESXi and vCenter Server that cover many different areas. Not all of these statistics are useful in most cases and if you tried to monitor them all you would be quickly overwhelmed. Some statistics are only useful in certain situations such as troubleshooting a resource bottleneck but there are others that can provide key indicators to the overall health of your vSphere environment and should be constantly monitored. Some statistics are specific to hosts and others only apply to virtual machines, the below table lists some of the more important statistics that you should focus on when monitoring vSphere.

Full paper including the table detailing key performance metrics available here…

The polls will open next week for the annual VMware/virtualization top blog voting, so if you want to make sure your site is included make sure I have your blog listed on my vLaunchPad. This year will be a bit different, instead of just a top 25 we’ll also have categories kind of like they do at many awards shows. Some of the categories will be Best New Blog, Best Storage Blog, Blogger You Most Want To Meet, etc. I’m still playing with the categories so sound off in the comments if you have any ideas.

The iPad is becoming more and more popular in the enterprise, and not just for mobile workers. There is also a slew of iPad applications for VMware admins.

Many IT vendors see the iPad’s potential and are developing iPad apps that can manage their traditional hardware and software products. Xsigo Systems, for instance, has a very nice app called Xsigo XMS , which manages virtual I/O through the company’s XMS servers. There is also an iPad application called SiMU Pro that manages Cisco Systems Inc.’s Unified Computing System.

In addition, there are several iPad applications that can supplement the traditional VMware admin toolkit, including the vSphere Client and Secure Shell (SSH) applications. With the right iPad applications, VMware admins will reach a new level of management flexibility that’s not possible with traditional desktops and laptops.

TABLE OF CONTENTS

I. Top iPad applications for VMware management

II. Applications for remotely connecting to hosts and workstations

III. Top iPad applications for VMware networking

IV. General purpose iPad apps for VMware admins

I. TOP IPAD APPLICATIONS FOR VMWARE MONITORING AND MAINTENANCE
With the top iPad applications for infrastructure management, VMware admins can control basic functions, such as powering virtual machines (VMs) on and off and using vMotion.

These iPad apps mimic some of the functionality of the vSphere Client and service console, but they aren’t a full-fledge replacement. Even so, these iPad applications allow VMware admins to perform key virtualization tasks without a full-scale computer.

Read the full article at searchvmware.com…

It’s John Troyer’s birthday, for those that do not know John he’s VMware’s dynamic, social media and community person who will give you the shirt of his back if you ask. For those who do know him, well you probably already know this. I know John very well and he has graciously written the foreword on both my books. Two years ago I arranged a special surprise involving dozens of bloggers and community people for John in appreciation for everything he has done for the community, be sure and check out the videos to see his reaction to the surprise.

ESXi 4.1 brought changes to the patching process. Previously, the Host Update utility — an application included with the vSphere Client — could patch ESXi 4.0 hosts. VMware removed Host Update from ESXi 4.1, presumably to encourage users to upgrade to paid versions that are managed and patched with vCenter Server’s Update Manager. As a result, the only method left to patch the free version of ESXi is with the vihostupdate command-line utility, which is included in the vSphere Command-Line Interface (CLI).

Before using this method, it’s important to understand how the patches work and where to find them.

Read the full article at searchvmware.com…

VMware announced that ESXi will be the exclusive hypervisor of vSphere 5. As such, we will likely see a greater adoption of VMware’s smaller hypervisor.

ESXi can be either embedded on a server (boot from flash) or installed on existing servers, using the Installable version. The free version of ESXi, the VMware vSphere Hypervisor, includes support for virtual symmetric multiprocessing (vSMP) and thin provisioning. No additional features are included, which means the free version of ESXi cannot be managed by vCenter Server, because it does not include a vCenter Server agent. To gain additional features and a vCenter Server agent, you need to upgrade your ESXi license.

The ESXi installation uses about 5 GB of space. Any remaining space on the drive is automatically formatted as a Virtual Machine File System (VMFS) partition. The hypervisor needs roughly 32 MB; the additional space is used for VMware Tools as well as swap and core dump partitions.

If you already have existing licenses for ESX, you can also choose to deploy ESXi in place of ESX on a server. Simply download ESXi installable. Install it and then license it with vCenter Server, as you would a traditional ESX server. Follow the steps below to install and configure ESXi.

Read the full article at searchvmware.com…

Host resources are a precious commodity in virtual infrastructures. To maximize your return on investment and the benefits of virtualization, you must make the most of them.

VMware vCenter CapacityIQ reports on CPU, memory and disk I/O usage, which enables you to right-size vSphere infrastructure and prevent common virtualization challenges, such as virtual machine (VM) sprawl.

CapacityIQ is available as a standalone product and is also bundled with vCenter Operations, VMware’s new operations management software. At some point, CapacityIQ and Operations may merge into a single product. Until then, here’s what VMware’s resource-reporting and planning tool can do.

The capabilities of vCenter CapacityIQ
VCenter CapacityIQ is a pre-built virtual appliance, deployed from an Open Virtualization File format, so it can be exported directly into vCenter Server. VCenter CapacityIQ focuses on three areas in vSphere:

Read the full article at searchvmware.com…

I did a 3-part series on VMware snapshots years ago for Tech Target that was based on VI3, I recently updated the series to include changes that have occurred with the technology since the release of vSphere.

Part 1 - How VMware snapshots work

A disk “snapshot” is a copy of the virtual machine disk file (VMDK) at a certain point in time. It preserves the disk file system and system memory of your VM by enabling you to revert to the snapshot in case something goes wrong. Snapshots can be real lifesavers when upgrading or patching applications and servers. This article will go over everything you need to know about using snapshots with VMware, including what they are, how they work and advanced techniques.

Snapshot disk space used and rate of growth
If you create more than one snapshot of your virtual machine (VM), then you’ll have multiple restore points available to revert to. When you create a snapshot, what was currently writable becomes read-only from that point on. Using in-file delta technology, new files are created that contain all changes (delta) to the original disk files.

The size of a snapshot file can never exceed the size of the original disk file. Any time a disk block is changed, the snapshot is created in the delta file and simply updated as changes are made. If you changed every single disk block on your server after taking a snapshot, your snapshot would still be the same size as your original disk file. But there’s some additional overhead disk space that contains information used to manage the snapshots. The maximum overhead disk space varies and it’s based on the Virtual Machine Files System block size.

Read the full article at searchvmware.com…

Part 2 - Deleting virtual machine snapshots without wasting disk space

Taking snapshots of your virtual machines (VMs) is a useful way to preserve and restore VM configurations. But proper management is needed to avoid performance problems. In this tip, we’ll explore advanced snapshot management topics. (For a review of snapshot basics or review how VMware snapshots work, see my previous tip.)

Disk space and deleting multiple snapshots
It’s important to plan ahead and allow for ample disk space on your VMware virtual machine file system (VMFS) volumes for snapshot files. A good rule of thumb is to allow for disk space of at least 20% of the virtual machine’s total disk size. But this amount can vary depending upon the type of server, how long you keep the snapshots, and if you plan on using multiple snapshots. If you plan on including the memory state with your snapshots, you’ll also need to allow for extra disk space equal to amount of RAM assigned to the VM.

A VM with only one snapshot requires no extra disk space when deleting, or committing, it. (The term committing is used because the changes saved in the snapshot’s delta files are now committed to the original virtual machine disk file, or VMDK.) There is also an extra helper delta file that is created when you delete snapshots. It contains any changes that are made to the VM’s disk while the snapshot is deleted. The size of the helper delta file varies and it’s based on how long the snapshot takes to delete. But it’s generally small, because most snapshots are deleted in less than an hour.

Read the full article at searchvmware.com…

Part 3 - Troubleshooting VMware snapshots

Virtualization administrators can use snapshots in vSphere to travel back in time and figure out what went wrong with their virtual machines (VMs). In part one of this series, I discussed how to use VMware snapshots. In part two, I explained how to delete snapshots without wasting disk space. But what do you do when your snapshots start acting funny? In this tip, we’ll troubleshoot potential problems that may come up when using snapshots in vSphere.

Locating VMs that have snapshots
Finding out which VMs have snapshots can be challenging. In VMware Infrastructure 3, there wasn’t a centralized, built-in way to accomplish this task in the vSphere Client or vCenter Server. You had to use methods, such as scripts and command-line utilities, that made locating snapshots difficult. But there were some enhancements in vSphere that made locating snapshots much easier. Here are a few of the methods that you can use.

Method 1: Find command
Use the find command in the ESX service console or ESXi Tech Support Mode

1. Log in to the console.
2. Change to your /vmfs/volumes/ directory.
3. Type find -iname “*-delta.vmdk” -mtime +7 -ls to find snapshot files that have not been modified in seven days or simply find -iname “*-delta.vmdk” to find all snapshot files.

Read the full article at searchvmware.com…

Hyper-V Dynamic Memory is Microsoft’s answer to VMware memory overcommit.

Dynamic memory allocation and memory overcommit both aim to improve memory management in virtual server infrastructures, and they even use common technologies. But they take different approaches and offer very different user experiences.

These differences — plus the fact that Hyper-V lacked dynamic memory allocation until this year — have spurred much debate among VMware and Microsoft users about the merits of each feature. In this face-off, two virtualization experts debate the pros and cons of Hyper-V Dynamic Memory and VMware memory overcommit.

Hyper-V dynamic memory allocation: A superior approach
vs.
VMware memory overcommit: Do it right to begin with

Read the full article at searchservervirtualization.com…

VMware products have come a long way since the mid-2000s. Back then, virtualization was more of a niche technology with a cult following.

Today server virtualization has become ubiquitous, and VMware products dominate the market. The company has capitalized on this success and now offers other data center platforms, tools and services. Currently, VMware is making a concerted push into the cloud-computing market with products and initiatives such as vCloud Director, VMforce and Cloud Foundry.

Recently VMware has enjoyed record growth, as demonstrated by its recent acquisitions and Q1 revenue. To trace the company’s success, let’s review its recent milestones, product launches and initiatives. We’ll start in 2004, with the first VMworld conference.

In the Beginning: VMworld 2004

The first VMworld had 1,400 attendees — which isn’t bad, but far less than the 17,000 attendees in 2010. Over the past seven years, VMworld attendance has increased dramatically, which reflects the growing popularity of virtualization (see Table 1).

Read the full article at searchvmware.com…

Your customer’s vSphere environment may seem healthy enough at first glance, but external appearances can be deceiving. Hidden problems may lurk under the cover that can eventually cause the environment to become unhealthy.

Not all problems that can occur are obvious to VARs because virtualization is much more complicated than traditional computing environments. There are many more moving parts that can lead to more complications. Seemingly trivial things such as simple configuration settings can have a ripple effect on the environment if they aren’t set correctly. Virtualization is all about sharing a limited set of resources amongst many virtual machines (VMs) and ensuring the optimum performance and availability you need to ensure the environment stays healthy.

A vSphere environment health check is one of the most valuable services that you can offer to customers because vSphere needs constant maintenance to keep it operating efficiently and problem-free. A good health check should be done on a periodic basis and is similar to a home inspection in that it documents the environment and checks the many different vSphere components to identify any existing or potential problems that can occur. Health check results can also be used to identify potential optimization and performance improvement opportunities that VARs can turn into value-adds.

Read the full article at searchsystemschannel.com…

I just launched my new vBookshelf section of vSphere-land which can be found under the vInfo drop-down menu. I’ve gathered together over 30 books related to VMware and virtualization and have links and information on them. I think I’ve put together a pretty complete selection of good books that are available but if I’ve missed any please let me know. I’d also like to highlight 4 good books that have been recently released.

Click here to access the vBookshelf section of vSphere-land.com

Title: Visible Ops Private Cloud: From Virtualization to Private Cloud in 4 Practical Steps

Authors: Andi Mann, Kurt Milne, Jeanne Morain

Publish Date: April 8, 2011

Title: VMware vSphere Design

Authors: Scott Lowe, Maish Saidel-Keesing, Forbes Guthrie

Publish Date: March 8, 2011

Title: VMware vSphere PowerCLI Reference: Automating vSphere Administration

Authors: Luc Dekens, Alan Renouf, Glenn Sizemore, Arnim van Lieshout, Jonathan Medd

Publish Date: April 12, 2011

Title: VMware ESX and ESXi in the Enterprise: Planning Deployment of Virtualization Servers (2nd Edition)

Authors: Edward Haletky

Publish Date: February 18, 2011