Sunday, April 29, 2012

Device or Resource Busy Error on vSphere client

I can hardly count the instances where anyone working with VMware vSphere environment has not encountered this error "Device or Resource Busy"

There are  some reasons why this error coming up.

Few instances mainly can be listed as follows

  • When you browse a datastore, it does not have any files or folders.
  • Under /vmfs/volumes/ there are no files or directories.
  • While deleting a datastore, you see the error:

    Device or Resource Busy
  • Deleting the partition table of this datastore does not resolve the issue.
  • Deleting a vmdk fails for the VM which is not longer in use 
There are few articles you can find here which discusses all these conditions and how to resolve them.   and

If you have encountered other instances which are not documented then you can always provide the feedback to the article and it will be updated accordingly.

If you search you may find other articles which highlights other issues apart from the listed above.

Hope you will find this information useful.

Friday, April 27, 2012

vCO and PowerShell- Interested?

Recently came across a discussion on how to use PowerShell with vCO (vCenter Orchastrator) by Alan Renouf (@arenouf) and Igor Stoyanov (R&D @VMware).

These are some examples I am posting here for your reference.

vCO Powershell blog post:

Community posting on topic PowerShell script and the Orchestrator:

vCO PowerCLI blog post:

Official documentation:

Example of using vCO powershell plugin to integrated with the View powercli

Upon research I found few more blogs out there

One by a VMware employee Arnim van Lieshout (@avlieshout) on using esxcli with PowerCLI

and another one by Paul Woodward (@woodwarp) on scripting esxcli commands.

If you come across any other links then please send it off to me and I will update here.



Cloud Storage - Choose wisely

VMware ESX/ESXi/Hypervisor comparisons

Main Difference between ESX and ESXi

VMware ESXi is VMware’s most advanced hypervisor architecture. Learn about the differences with the previous generation architecture, VMware ESX
Capability ESX 4.1 ESXi 4.1 ESXi 5.0
Service Console Present Removed Removed
Admin/config CLIs COS + vCLI PowerCLI + vCLI PowerCLI + vCLI (enhanced)
Advanced Troubleshooting COS Tech Support Mode ESXi Shell
Scripted Installation Supported Supported Supported
Boot from SAN Supported Supported Supported
SNMP Supported Supported (limited) Supported
Active Directory Integrated Integrated Integrated
HW Monitoring 3rd party agents in COS CIM providers CIM providers
Serial Port Connectivity Supported Not Supported Supported
Jumbo Frames Supported Supported Supported
Rapid deployment and central management of hosts via Auto Deploy Not Supported Not Supported Supported
Custom image creation and management Not Supported Not Supported Supported
Secure syslog Not Supported Not Supported Supported
Management interface firewall Supported Not Supported Supported
See the KB article for a detailed comparison. There is one more KB for such comparison.

Compare ESXi to Other Vendors' Offerings

Hypervisor Attributes VMware ESXi 5.0 Windows Server 2008 R2 SP1 with Hyper-V Citrix XenServer 5.6 FP1
Small Disk Footprint

144 MB disk footprint
(VMware ESXi)

>3GB with Server Core installation

~10GB with full Windows Server installation

OS Independence

No reliance on general purpose operating system
(VMware ESXi)

Relies on Windows 2008 in Parent Partition

Relies on Linux in Dom0
management Partition
Hardened Drivers

Optimized with hardware vendors

Generic Windows drivers

Generic Linux Drivers
Advanced Memory Management

Ability to reclaim unused memory, de-duplicate memory pages, compress memory pages

Only uses ballooning. No ability to de-duplicate or compress pages.

Only uses ballooning. No ability to de-duplicate or compress pages. Does not adjust memory allocation based on VM usage.
Advanced Storage Management

Lacks an integrated cluster file system, no live storage migration

Lacks an integrated cluster file system, no live storage migration, storage features support very few arrays
High I/O Scalability

Direct driver model

I/O bottleneck in parent OS

I/O bottleneck in Dom0 management OS
Host Resource Management

Network traffic shaping, per-VM resource shares, set quality of service priorities for storage and network I/O

Lacks similar capabilities

Lacks similar capabilities
Performance Enhancements

AMD RVI, Intel EPT large memory pages, universal 32-way vSMP, VMI paravirtualization, VMDirectPath I/O, PV guest SCSI driver

Large memory pages, 
4-way vSMP on Windows 
2008 and Windows 7 VMs only

No large memory pages, no paravirt guest SCSI device, Requires inflexible SR-IOV
Virtual Security Technology

VMware VMsafe™
Enables hypervisor level security introspection

Nothing comparable

Nothing comparable
Flexible Resource Allocation

Hot add VM vCPUs and memory, VMFS volume grow, hot extend virtual disks, hot add virtual disks

Only hot add virtual disks

Nothing comparable
Custom image creation and management

VMware Image Builder allows administrators to create custom ESXi images for different types of deployment, such as ISO-based installation, PXE-based installation, and Auto Deploy.

Nothing comparable

Nothing comparable
Auto Deploy

vSphere Auto Deploy enables faster provisioning of multiple hosts. New hosts are automatically provisioned based on rules defined by user.

Requires in-depth setup in Systems Center Configuration Manager

Nothing comparable
Management Interface Firewall

ESXi Firewall is a service-oriented and stateless firewall that protects the ESXi 5.0 management interface. Configured using the vSphere Client or at the command line with esxcli interfaces.

Nothing comparable

Nothing comparable
Enhanced Virtual Hardware

32-way virtual SMP, 1TB virtual machine RAM, Non hardware accelerated 3D graphics, USB 3.0 device support, Unified Extended Firmware Interface (UEFI).

4-way virtual SMP only, 64 GB RAM per virtual machine

8-way virtual SMP only, 32 GB RAM per virtual machine

Product Update Releases by VMware

VMware has released the following upgrades to the existing products which are mainly categorized in to the following.

Datacenter & Cloud Infrastructure

             Application Platform

Infrastructure Operations Management

End-user Computing
     All the other downloads can be accessed from here.

My Linkedin Groups for Certifications

I have created few groups on Linkedin for all the VMware lovers which is focused on certifications such as VCP, VCAPx-DCD, VCPx-DT, vCloud and VCAPx-DT (coming soon)

Here are the links so please feel free to join and discuss.

You can also follow me on Linkedin and Twitter @mandivs

Thanks for your time.

Technological Terms with VMware

I came across various Technological Words while reading or dealing with issues


You are all welcome to add other words to this list and I will try to aggregate all the information available to clearly understand these terms (which may include the blogs by others as well) and official documentation from VMware on them.

Leave the Feedback here and I will update the post when things are ready.

Thanks for all your support.

Thursday, April 26, 2012

VCAP5-DCD - The Hot Target for VCDX

I am thinking to start blogging about the Objectives of both the exams soon.

VCAP4-DCD  - yes that's right this is version 4 for now as version 5 is not GA yet (but will be soon)

VCAP5-DCD - Once it becomes GA then link will be available.


All other certification details are available here.

You can also find out the blog posting by others on the similar subject.

All the discussion and material is purely made for my own study purpose so you can make the changes and use it accordingly.

Brain dumps people - this is not the place you should visit as there won't be any questions and answers here ;-)

Well lets get started.

I am going to start posting the objectives for the Design Exam as it will be GA in near future. If any one wants to do any guest posting, all are welcome to contribute and share the knowledge.

Just contact me offline through @mandivs


Objective 1.1 – Gather and analyze business requirements 
(e.g. current availability, manageability)

Skills and Abilities

·         Determine the relevant data set required to understand the current customer environment.
·         Given a design requirement and data set within a multi site environment, determine which components would be included in a design.
·         Given results of a requirement gathering survey, identify the business requirements.
·         Given one or more business requirements, analyze and determine the impact of the requirements on the design.


VMware Virtualization Case Studies                                 

-          A good  VMware design matches products, features, and capabilities to business needs
-          Business need is the combination of many things summarized by: requirements, constraints, assumptions
-          Resulting in the identification of – design decisions, justifications, impacts, risks
Architecture vision
-          Scope – project boundaries, eliminate creep
-          Goals – business problems we’re solving with measurable results
-          Requirements – must meet
-          Assumptions - valid but not proven, as few as possible
-          Constraints – limit design choices
-          Risks- every design will have them, find them and communicate them
The vision will guide the project through its phases
Which may not fall into requirements and constraints are fall in to assumptions
Take the assumptions from customer and get the clarity – valid but not proven
e.g. customer budgetary concern, don’t have enough infrastructure but will purchase additional hosts in future
Wrote categories on the board
Requirements, assumptions, constraints and risks (which are not conveyed properly or not clear)

Five steps of design
1)      Initial Design meeting – scope, goals, requirements, constraints, who should be invited?
2)      Current state analysis – complete datacenter inventory, virtualization candidates, tools, constraints, assumptions
3)      Stake holder and SME training educate SMEs who can help make informed design decisions
4)      Design sessions – design decisions with stakeholders/SMEs, no surprises later
5)      Design deliverable – documentation capacity analysis, hosts, vCenters, clusters, network, storage, monitoring, patching, backup, restore, DR, security, installation, operations, scalability, support, logical, physical etc.

Current state Analysis and vApps
-          Identify virtualization candidates and applications (identify non-virtualization candidates)
-          Capture baseline performance metrics including average and peak loads (feeds into capacity requirements, feeds into consolidation rations, can be used for comparison purposes)
-          Identify unique dependencies
-          Identify reusable hardware for the design
Design best practice Gems
-          Avoid known problems and achieve predictable results
-          Use as flexible guidelines, not rigid rules
-          Blend with the business unit goals and requirements
-          Evolve with technological advances
-          VCDX defense caution (Requirements, constraint, Assumption or Risk?

Managing downtime

-          So while major disasters may be infrequent events, the risk of downtime is still constant and costly.  The graph shown here breaks down the average cost of downtime by industry, but you can see that the average is around $1.5 million dollars per hour.  This includes not only lost revenue to the company, but also lost employee productivity and damage to a company’s relationship with partners and suppliers.  

-          Another key fact to point out is that downtime is common.  More than half of companies experience some amount of downtime in a given year, and some analysts have found that around a quarter of companies have had to declare a disaster at least once in the past five years.  Often these events are due to causes like an extended power outage, something you wouldn’t normally think of as being a disaster.  Companies who weren’t prepared to handle such disaster recovery situations would stand to lose millions of dollars and, if recovery takes long enough or is ultimately unsuccessful, could also lose their business.

Recovery Risk

-          So while major disasters may be infrequent events, the risk of downtime is still constant and costly.  The graph shown here breaks down the average cost of downtime by industry, but you can see that the average is around $1.5 million dollars per hour.  This includes not only lost revenue to the company, but also lost employee productivity and damage to a company’s relationship with partners and suppliers.  

-          Another key fact to point out is that downtime is common.  More than half of companies experience some amount of downtime in a given year, and some analysts have found that around a quarter of companies have had to declare a disaster at least once in the past five years.  Often these events are due to causes like an extended power outage, something you wouldn’t normally think of as being a disaster.  Companies who weren’t prepared to handle such disaster recovery situations would stand to lose millions of dollars and, if recovery takes long enough or is ultimately unsuccessful, could also lose their business.

 Additional Reading

Recovery Time Objective (RTO) is the period of time within which systems, applications, or functions must be recovered after an outage. This defines the amount of downtime that a business can endure, and survive. Recovery time includes: fault detection, data recovery, and bringing applications back online.

Recovery Point Objective (RPO) is the point in time to which systems and data must be recovered after an outage. This defines the amount of data loss a business can endure. Different business units within an organization may have varying RPOs.

Business Continuity is a holistic approach to planning, preparing, and recovering from an adverse event. The focus is on prevention, identifying
risks, and developing procedures to ensure the continuity of business function.

Disaster recovery planning should be included as part of business continuity.

Objectives of Business Continuity:
- Facilitate uninterrupted business support despite the occurrence of problems.
- Create plans that identify risks and mitigate them wherever possible.
- Provide a road map to recover from any event.

Disaster Recovery is more about specific cures, to restore service and damaged assets after an adverse event. In our context, Disaster Recovery is the coordinated process of restoring systems, data, and infrastructure required to support key ongoing business operations.

Business Continuity Planning (BCP) is a risk management discipline. It involves the entire business--not just IT. BCP proactively identifies vulnerabilities and risks, planning in advance how to prepare for and respond to a business disruption. A business with strong BC practices in place is better able to
continue running the business through the disruption and to return to “business as usual.”

BCP actually reduces the risk and costs of an adverse event because the process often uncovers and mitigates potential problems.

In summary you have 3 major complications in a traditional DRP that is based on physical systems:

First, a variety of information and data that needs to be protected. All of which needs to be available to ensure recovery. These different kinds of data require different processes and tools. For example, backing up system disks (which are typically on internal storage) uses a different process than backing up data disks. Tracking hardware configuration requirements is also difficult. A common approach is to use spreadsheets, which easily become out of date or get lost. And backups used to protect data can be easily misplaced or corrupted.

Second, a very complex recovery process. Organizations are also faced with a complex recovery process with lots of steps, which can cause recovery to fail. For example, it is easy to miss a hardware dependency that leads to a failure and additional steps. Given the number of manual steps, it is easy for the staff who are executing recovery to make errors that impede recovery. All in all, the process can easily take days, and maybe even longer.

Third, DRPs are very difficult to test. Organizations face significant difficulties testing recovery plans. Tests may require additional servers and storage arrays so that the recovery environment is not disturbed. It is also very difficult to test without disrupting production systems and protecting the process.

Disaster protection for services tends to be tiered. Tier one includes services for which no downtime at all can be tolerated. These services tend to be deployed from the start in active-active configurations. For the remaining services, however, disaster recovery plans are typically in a three-ring binder to be used in the event of a disaster. Instructions in the binder describe how to recover a particular server, configure particular hardware, reinstall the operating system, recover from tape, and so forth.

Of course, these steps are very manual, and they are often very difficult to test.

A Recovery Point Objective is the point in time restored systems have to be started with. A Recovery Time Objective is the amount of time allowed between the disaster and the time when you will have recovered systems to match the RPO. The terms “recovery point objective” and “recovery time objective” will be discussed in more depth later in this course.

Disaster recovery planning  and business continuity planning  are two different things. A DRP is designed to be a plan or a set of procedures that guides employees during the chaos of a disaster and the time immediately following a disaster. It is focused on safeguarding assets and personnel and it is procedure-oriented. It will include things like a step by step procedure on how to get critical systems back online fast at the recovery site. By nature, it is designed to provide a temporary safe harbor for the business. This involves failover planning. Failover is the process by which key business systems are transitioned rapidly during an emergency to a remote recovery site. In contrast business continuity is the process of keeping daily operations running after the disaster.

A Business continuity plan, or BCP  provides guidance on how to keep day to day business operations going at the recovery site. Business continuity planning also changes depending on perspective. For example, the IT department might be concerned mainly about data backups. (Data backups must continue to be made even while operating at the recovery site.) Other departments might have a wider view. To get a call center back online, you not only need your customer data, you also need a facility with desks and phones.

BCPs  should specifically address three things. First, how to run business operations with the smaller capacity of the recovery site. Second, how to prevent interference between recovery operations and the production operations that were formally run at the site. And third, how to eventually failback to the original primary site.

Talk about RPO (recovery point objective) – which is about how much data is lost, i.e., since the last BU.  We can handle most anything, from minutes to years.

Also talk about RTO (recovery time objective) – which is about how quick we can get back to work.  We cannot do real time or near real-time.  Hours is generally what we can do, but it is very important to understand we must test to determine exactly what is possible 

Continued .......
Objective 1.2 – Gather and analyze application requirements [soon]

Virtual Disk Format 5.0 on VMware ESXi

Let me ask you a question.

How much you know about the virtual disk format in detail??

Its in the format of vmdk, it resides on VMFS volume, Descriptor file and Raw Data files stored in two separate disks etc. etc.

Anything else you can think of now.............

Here I am ending your anxiety to know everything about the virtual disk format version 5.0 (which is the recent one).

Have a look at the document here.

If you are reading this through Twitter then DO NOT forget to RT the Tweet ;-)

Enjoy reading something interesting which you will not find in any published book either. Just Kidding.

Take care.

Wednesday, April 25, 2012

Why my versions are not matching? eg. ESX/VC/VMware Tools

Lot of people are curious about the versions numbers they see on ESX/ESXi/vCenter/Virtual Center server, VMware Tools etc. etc.

Have a look at the following article

This article has all the information about the version matrix

Additional Information section has 3 more links

Try matching all the build numbers in your environment and verify if you are not missing any critical and Important Patches.

As always leave the Feedback !!

Data Recovery Services for Data Loss

Recently I attended onsite session from Seagate Recovery Services and few weeks back from Kroll Ontract Services.

These two companies are PROs in the Data Recovery services.

For media they can recover could be from anything which can store data. Yes - anything.

Now lets come to the point where you have a definite corruption with VMFS volume or have a major impact on your storage devices which are used to store virtual machines.

Once you open the case and find out there is no other alternative apart from contacting Professional Data Recovery Services to recover the lost data, refer and bookmark our KB 1014513 which has the contact information of both companies.

Now if you know any other company who provide similar services like Kroll and Seagate then provide the feedback to the article with contact information  for that company.

There are few goodies offered by Seagate and one has really critical steps on it which I like to share with all the VMware users. These steps are very useful in order to recover the data properly. Stick the print out on your desk so that visitors can read them :-)

Good Luck !!

NetFlow usage on ESX / vSphere Environment

I came across with few articles and official documentation on using NetFlow on Virtual Switches and vDS.

For using NetFlow on vSwitch/es look at this guide

Configuring NetFlow on ESXi 5.0 is described here.

There is a Evaluator's Guide also available for vSphere 5.0

For vDS Best Practice Venky @VMWNetworking (from VMware) has nicely explained here.

Monday, April 23, 2012

Thinking of Hardening your VMware Environment - check this out.

Today's technological advancement has given the users access to the information very easily. With proper set of rights and permissions are not available as Standards as the design and implementation varies from company to company.

To harden your vSphere Environment you need to either develop your own custom tool to monitor and impose your security standards or you can go with some existing tools developed by experts which are listed here.


By William Lam @lamw

Script is available here.

By Alan Renouf @alanrenouf

Security Public Drafts available for vSphere 5.0

If you want the difference between ESX/ESXi 4.1 and ESXi 5.0

Looking for information on vSphere 4.0

And if you still running ESX/ESXi 3.0


Finally for vCloud Director 1.x

Online Diagrams - how cool is that?

I just came across with this cool tool which you can find at

Explore the endless possibilities when you are on conference call with people using Webex or any other tool and wanted to show them right away some designs, (without using the MS Paint like tool of Webex), that's where this HTML5 based tool coming in to the picture.

You can export the drawings, color them, save them, make flowcharts, put arrows, etc. etc.

Enjoy and leave the feedback if you like it.

Friday, April 20, 2012

How to search a KB with specific Title on VMware?

I came across this questions few times with my own questions while troubleshooting the issue and I was in need of getting the results from to give me the results of specific article with the search criteria/words inside.

One of our Knowledge Architect has given a nice hint on how to search the article which contains specific word/s.

e.g. To find out all the article which as "My VMware" in the Title then put the search "allintitle: "My VMware"" on the site.

Test the search results with your requirements and let us know through the feedback if the results needs an improvement or if the results are missing some information which you expected to get. e.g. purple screen, vDS, Nexus etc. etc.


I just saw this image and was thinking how perception can make things different.

The Title is mis-communication but we can see in real life the same thing happens a lot with different level of mind set and the thought process behind each perception on interpreting the facts.

No vExpert for you - what's next???


By the time you read this post you will be definitely in the same boat as me (or may be not).

I did not get vExpert this year (even being an employee) but I have rather take this as a challenge and will apply next year to get that.

Whomsoever is missed this opportunity, I have just one suggestion, try harder and prove yourself.

Bring all the VMware you know and flush it down to people who are waiting for such Info.

@rayheffer @vcdxnz001 and @gurusimran has supported in this stance and I'm sure others too.

I just want to thank all the people who are there for us to get the vExpert.


Running VMware Workstation 8 as a server with shared virtual machines

This is a cool video which will make you think what else can you do with Workstation 8 from VMware.

There are other possibilities which you can uncover and let us know about it by leaving the comments here.


Creating Custom Persistent Firewall Rules on ESXi 5.0

With ESXi 5.0 you dont have to worry about having persistent custom rules for Firewall on ESXi server.

With the following two steps you can make that happen.

1. Copy the newly defined service.xml file onto persistent storage (such as /store/), or onto a VMFS volume (/vmfs/volumes/volume/).

# cp /etc/vmware/firewall/service.xml location-of-xml

Note: A VMFS volume can be stored in a single location and copied to multiple hosts.

2. Add these lines to the/etc/rc.local file on the host:

cp location-of-xml-file /etc/vmware/firewall
esxcli network firewall refresh

Note: Where location-of-xml file is the location to which the file was copied.

For more information check out KB 2008226.

vExpert - Announcement

@jtroyer has released the final list of VMware vExperts so check it out.

If you see your name on it, start the party!!

Enjoy the status.

Well if you are curious then I am not vExpert yet.

Wednesday, April 18, 2012

VMworld 2012 - Call for Papers

VMware is calling all VMware community to San Francisco to attend the VMware 2012

Submit your presentation here and cross your fingers

Good Luck!!

vSphere Security --> Hardening Guides differences

There is another Draft available which is discussing the differences between ESX 4.1 and ESXi 5.0 Hardening guidelines.

Feel free to leave your comments which will be very important to improve the functionality.

vSphere 5 Security Hardening Guide Draft


VMware has released a Draft for vSphere 5 Security Hardening Guide in .xls format which you can find here

Leave your feedback to improve the content.