TheSaffaGeek

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Category Archives: Virtualisation


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vSphere 4.1 to vSphere 5.1 Upgrade Resources and Experience

In the coming months I am due to upgrade at least one client from vSphere 4.1 to 5.1 and so I have been collecting some great notes and articles around doing the upgrade to 5.1. This is a blog posting in progress and I am planning on updating it with how the upgrades went after I have done them.

For the 4.1 to 5.0 upgrade of the environments I am planning on following what has worked for me in the past which I listed and blogged about in my posting here. The links and blogs I have found for the upgrading to vSphere 5.1 are listed below and are the ones I will be reading and following for the upgrades:

If you know of more please do tell me so I can update the list for myself and the community at large

Gregg


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VCDX Spotlight: Chris Fendya

Name: Chris Fendya

Twitter Handle: @ChrisFendya

Current Employer: World Wide Technology www.wwt.com

VCDX #: 96

How did you get into using VMware?

I first started using VMware back in the GSX days when researching a way to save data center space for a global supplier to energy products I worked for. I remember hearing about this “vMotion” thing which pushed me to look into ESX. I built a small environment, staged the scenario, issued the vMotion command, and was hooked. I will never forget that moment and what followed by relaying the good news to our CIO. He promptly challenged me on what I just described to him. The demo date was set, I again built the scenario, and in a small conference room showed our CIO the power of vMotion. He just smiled and said “Continue forward and get this stuff in our data center!”. I haven’t stopped with VMware since that day and that was over eight years ago. It’s been an amazing adventure seeing VMware grow and watching the changes and impact it has made to all our lives and how we work.

What made you decide to do the VCDX?

I was challenged by an old boss to go after it a couple of years ago back when it was in its infancy. I began reading up on what all was required, the process, and reading others blog about their experience of the journey. Saying I was intimidated is an underestimate but the funny thing was I was inspired and challenged all at the same time.

How long did it take you to complete the whole VCDX journey?

My journey lasted a couple years. I did not pass my first defense. That first defense was an eye opening experience for me and drove me to go after it a second time. When I received notice I failed after my second defense, I had a range of emotions and for a long time decided the certification wasn’t for me. When VMware announced a final defense for VCDX4 at VMworld 2012, I had many within the community contact me and encourage me to give it another attempt. Had it not been for them, I don’t believe I would be writing this right now 😉

What advice would you give to people thinking of pursuing the VCDX accreditation?

Take their time! It’s not a race to get the certification. Learn all you can about every aspect of an entire solution. Where the certification is obviously centered around VMware, it will challenge you on every aspect of a design and a total solution (Networking, Storage, Compute, Business impact, etc) and how each and every one of those relate to VMware and the end design. I found I was questioned on things I never thought of during my preparation and honestly, sometimes things I didn’t know. The panel isn’t there to make you look dumb or prove that they are smarter than you. They will help you through it as much as they can, so as much as it’s about challenging you on what you know, it’s also about your thought process and how you approach a problem and work through it.

If you could do the whole VCDX journey again what would you do differently?

I believe things happen for a reason so to say I would do it differently or have it happen differently…No. I obviously would’ve loved to pass on the first or even second try but not doing so had it’s own rewards 😉

Life after the VCDX?  How did your company respond?  Was it worth it?

I work for a pretty amazing company! Throughout the entire process they embraced my journey, encouraged me along the way, and in the end were extremely proud when I shared the good news. They wrote this blog article to celebrate the news which I was honored to have done.

I get the “Was it worth it” question a lot. Mostly from customers who have heard of the certification and want to know about it and my journey but also from others in the community. I always respond ABSOLUTELY! I learned an immense amount about designing solutions and myself as an individual. In addition and probably most important, I became a better Architect, Engineer, and Consultant. The people I met and interacted with throughout the entire process has been amazing… Many of those who I know will be a part of my career for a very long time!


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My VCAP5-DCA Experience

Yesterday the day finally came and I attempted the VCAP5-DCA exam. For anyone that doesn’t know what the exam entails then the below description for the VCAP5-DCA Blueprint should help:

The VDCA510 exam consists of approximately 26 live lab activities and a short pre-exam survey consisting of 9 questions. Live lab activities consist of multiple tasks, where each task is scored. The total number of activities provided is based on the total number of tasks. Because of this, the actual number of lab activities may vary slightly between exams.

As I am under NDA and because I want to maintain the high level of the exam I’m not going to go into specifics but more my experience of the exam, what I used to prepare, how it compared to the VCAP4-DCA and what I would recommend to someone looking to attempt the exam.

The Experience

I did the VCAP4-DCA twice so I knew what to expect a lot more but my experience of this exam was fairly different. I arrived at the testing centre far too early (an hour and a half before my exam), my slot was at 11am but I wanted to miss traffic and forgot it is Half Term for UK schools so I had a very easy drive in. I waited in the testing centres cafeteria, ran through a number of commands, and advanced settings in my head that I wanted to remember just in case I was asked to do them in the exam. I was called through and did the usual security clearances, photo’s, signing sheets and removing my watch etc. as Pearson are very strict now on what you can take in (no drinks,watches,phones,food,sweets). I then got setup on my testing station, said a little prayer and began the test.

This is my third attempt at a VCAP-DCA exam although my first VCAP5-DCA attempt but for my VCAP4 attempts I had loads of problems of the screens hanging when I tried to flick over, making a stupid mistake by not reading a question carefully and essentially ending my exam early and for the VCAP5-DCA beta I never even got to question 1 as the lab wouldn’t show up for me. This time however the exam worked really well, the resolutions were much better and therefore allowed me to work in multiple screens without having to move around things too much and I made sure I read the questions very carefully so to not make any mistakes. Personally, I thought the VCAP5-DCA was harder than the VCAP4-DCA as for the VCAP4 they seemed to hand hold you a bit more and almost tell you what you should do to complete the task whereas for the VCAP5 they expect you to know what solution would fulfill the requirement outlined in the question. There were much less low-end questions and quite a few high-end ones where I had to rely on experience to know how to do things that I would not have learnt from any of my study resources. Although it was harder I personally enjoyed it more, now that’s not to say the exam is enjoyable as it REALLY tests your skillset but I felt it was more focused on real world requirements of a VI Admin/Consultant rather than the skill of regurgitating information. I was on my last task when my time ran out which I’m pleased about as it meant my time planning was almost perfect and I got through enough tasks and hopefully did them correctly to give myself a good chance of passing this time. I did skip one or two that I felt I wouldn’t be able to do in the fast paced way the exam requires you to do tasks but this did give me more time to do the things I knew correctly (I hope)

What I used to prepare and what I would recommend using

The resources I used to prepare are listed on my VCAP5-DCA and DCD Study Resources Page already so I’m not going to go into too much detail there but I do have to give special thanks to Josh Coen, Jason Langer,David M Davis and all the US vBrownbag guys as all their resources were priceless in my studying for the exam and I would highly recommend watching the vSphere 4 VCAP resources David did around troubleshooting and Management especially as even though they are on vSphere 4 they are highly applicable and as ever of a very high level.

What wasn’t and is not listed on that page which I did mention a bit about above that I needed in the exam was real world experience with the solution and the technology. I am very fortunate that I work for an IT consultancy specialising in virtualisation and for the past year I have been designing and rolling out vSphere 5 at an enterprise level to customers, which meant I had to really learn what everything did to ensure what I recommended and built for the customer was the best. Now I know everyone can’t/hasn’t had that kind of experience but what I also did that I didn’t do enough of for my VCAP4 attempts was spend loads and loads of time in my home lab building, breaking and fixing every single piece mentioned in the exam blueprint. I worked out that For the last month whilst preparing for the VCAP5 I spent around 55-60 hours practicing in my lab which is a serious amount seeing as I was at VMworld Europe a few weeks back. I believe this piece is as important if not the most important part of preparing for the exam as this exam isn’t like the VCP or any other exam I’ve done before as it is 100% lab based and you are under extreme time pressure to get things completed and so you need to know how to do something like it is second nature and know how things are connected. Micro servers are really cheap, it is worth the investment in getting one or two, and some shared storage and spending the time practicing.

Summary

The exam was very challenging but I hope I have done enough and the amount I have learnt by preparing for this exam is only going to help me do my job better and feel more comfortable doing my job now with the knowledge and skills I have learnt but preparing for the exam. If you are thinking of trying the exam then I would highly recommend it, it is a challenge but it’s one that isn’t impossible and it will push you to that next level. The resources out there for preparing are amazing and are extensive. Make sure you don’t cut any corners and practice, practice and practice some more as I was able to do a few things only due to me forcing myself to practice every single method of doing things. Also, let your partner know you are aiming for the exam, I know this is a drop in the ocean compared to the time you need for something like the VCDX but to fully prepare for the exam you will need to study in the evenings after work and for all of your weekends.

Good luck to anyone attempting the exam and hopefully I will be able to update this posting stating I passed in three weeks’ time

Gregg

*UPDATE* I’m super pleased to say that I got my results back and I PASSED!!! Super pleased and now onto my VCAP5-DCD


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EMEA #vBrownbag

vBrownBagLogo-150x150That’s right, after having spoken to the infamous APAC and US vBrownbag teams at VMworld and via the VMware vExpert communities Arjan Timmerman and I have thrown our hats into the ring and have asked to borrow the guys vBrownbag’s and show the world that the EMEA VMware guru’s are the some of the best in the world.

We are looking to start doing them within the next few weeks and need all the VMware talent in EMEA to put their hands up and come present and for everyone to join the calls/webinars and contribute. We are looking to possibly follow two different tracks so as to not repeat what the APAC and US guys have done and so will be looking for people to present on objectives in the VCP5-IaaS and VCP5-DT exam blueprints. You can do any of the objectives so if you want to do the last objective for the IaaS then first come first served/booked.

We are thinking of doing it every fortnight on a Tuesday starting on the 23rd of October although if there is a very good amount of interest which I trust there will be then we can make it a weekly occurrence. We are currently looking to do it at 7PM GMT to allow everyone in Europe the time to get home.Please spread the word and lets show the VMware community the talent EMEA has to offer. You can register here for the webinars

We have created a Google form for people to start putting in their interest and what they want to talk about here.

Gregg and Arjan


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VCDX Spotlight: Shane White

Name: Shane White

Twitter Handle: @ausvmguy

Blog URL: none (yet)

Current Employer: Southern Cross Computer Systems

VCDX #: 95

How did you get into using VMware?

In 2007, I started playing with Workstation. In the 2nd half of that year, I completed a training program I had been on for a while. I had seen ESX 2.5 installed but didn’t know a lot about it. When I asked my employer what the options were for continued training and/or specialisation and virtualisation was an option, I elected to go down this road. I got my VCP3 in October of that year and had the opportunity to do nothing but VMware onsite for the next 3 years or so with one of our clients.

What made you decide to do the VCDX?

I have always liked a challenge. With the exposure and skills I obtained onsite, and the satisfaction I got from working with VMware technologies, I decided that attempting VCDX would be enjoyable, definitely challenging, but not unachievable.

How long did it take you to complete the whole VCDX journey?

If you count from the time I decided to go for it, just under 2 years. Due to my commitments onsite, I couldn’t spend large blocks of time on my design. I achieved both VCAP4 exams in Nov 2010 (4 days apart!). I started working up the design in late November 2010 and had my 1st defence attempt in Singapore in November 2011, which was unsuccessful. The feedback received from this defense and from a 2nd unsuccessful defense in Toronto in May 2012 was applied to a revised submission aimed for defense at VMworld in San Francisco in August 2012. On the 3rd attempt, I was successful!

What advice would you give to people thinking of pursuing the VCDX accreditation?

I found it particularly valuable to have had practical experience working with a real environment. While a home lab is very useful as well, a real environment will encounter real design decisions and configuration issues that may not arise in a home environment.

Consider carefully the kind of design you are planning on submitting. My design was a totally fictitious one. My success shows that you can defend a fictitious design, but it is likely to be harder than if a real design is used.

Either way, read the blueprint and make sure you address ALL the criteria and that you know, not only what your design decisions are, but also understand why that choice was the most appropriate in your situation. This means having a good grasp on the business requirements that have a bearing on those decisions.

Don’t get discouraged if your 1st (or subsequent) attempts are unsuccessful. View it as an opportunity to improve. Achieving VCDX has been described as a journey, and the entire journey can be beneficial and bring satisfaction if you let it.

If you could do the whole VCDX journey again what would you do differently?

I’d read the blueprint more closely and more often! Apart from that, I wouldn’t do anything else differently. I enjoyed the whole experience and found the whole process immensely educational.

Life after the VCDX?  How did your company respond?  Was it worth it?

SCCS was definitely pleased with the successful defense.

As for me, the sense of satisfaction of achieving something significant is immense. The increased confidence when facing a situation is also noticeable.

Was it worth it? Absolutely. Even if I had decided not to reattempt, the process of developing the design, all the researching, and preparing for the defense and developing the presentation was of great benefit.


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VCDX Spotlight: Wade Holmes

Name: Wade Holmes

Twitter Handle: @wholmes

Blog URL: www.vwade.com

Current Employer: VMware

VCDX #: 15

How did you get into using VMware?

The year was 2004. I was an IT Specialist working in the IBM’s Business Continuity and Resiliency Services, and became aware of customers utilizing VMware for backup and recovery of their datacetners. I went to my manager at the time and told him about this trend, and that I was interested in becoming a VMware SME for IBM BCRS. I started working with ESX 2.0 and VirtualCenter 1.0, attended VMware training, and in 2005 became a VMware Certified Professional. During this time I spearheaded the creation and rollout of IBM BCRS’s first VMware based warm-site disaster recovery offering across the US, reducing the RTO of numerous fortune 500 clients. And so began the journey towards VMware excellence!

What made you decide to do the VCDX?

It was early 2008, and the VCDX certification was announced. The rigor of the requirements immediately attracted me to pursuing the certification. I knew this was a certification that could help further my career as an IT professional.

How long did it take you to complete the whole VCDX journey?

I completed the VCDX the summer of 2009, after taking the beta exam and defending during the first publically available defense. Below was the path I took before defending.

VCP on VI3
Enterprise Exam (beta)
Design Exam (beta)

I had no idea what to expect when coming to defend, and was extremely nervous. I spent countless hours preparing, reviewing my design, making sure I knew the in’s and out, and could justify every granular detail I documented. Luckily, that was exactly the approach necessary for me to be successful. I can’t describe how happy I was when I got a phone call that I passed and was a VCDX! (yes, back then I was actually contacted by phone to be informed I passed). In becoming VCDX #15, I was the first non-VMware employee worldwide to achieve the certification (as I worked for a partner at the time).

What advice would you give to people thinking of pursuing the VCDX accreditation? Dive in hear first to master your craft. Understand not just the what, but more importantly the why of architecture and design. Use the plethora of resources available to you online to become familiar with the format. Sign up for a VCDX Bootcamp to help prepare.

If you could do the whole VCDX journey again what would you do differently? Nothing except more sleep the night before the defense (if you can sleep).

Life after the VCDX?  How did your company respond?  Was it worth it

I believe I have a unique perspective on the VCDX program, having completed the VCDX program in 2009 as the first non-VMware VCDX worldwide, and then joining VMware and participating in the ongoing development of the program as a panelist. As an outsider looking in, the VCDX program was a goal that drove me to work on my craft, and become a better architect.

Since joining VMware, my participation in the VCDX program has only helped to hone my skills as a virtualization and cloud architect. It has forced me to sharpen my understanding of enterprise architecture principals, principals that aid me greatly in my day-to-day role dealing with virtualization and cloud solutions. I will be forever grateful to the VCDX program in providing a vehicle that forced me to push myself, and aiding me to take my career to another level.


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VCDX Spotlight: Randy Stanley

Name: Randy Stanley

Twitter Handle: @randystanley

Blog URL: http://www.randystanley.com

Current Employer: IT Partners

VCDX #: 94

How did you get into using VMware?

In 2003 I was working for a small software development company managing their business applications and supporting their software development team. Initially we began utilizing VMware GSX Server for those simple use cases trying to consolidate and save on our hardware spend where ever we could. In support of the software development team we also deployed ESX in a lab environment for testing and development purposes only. A fairly common introduction and use case early on in the adoption of VMware solutions. Plus, vMotion was the coolest freakin’ thing I had ever seen.

It wasn’t until I re-entered the consulting field in 2007 that I really started to dive deep into the VMware products and they have been an integral part of every solution we sell and deploy. It was this exposure to the VMware technology that really allowed me to develop my abilities and deepen my experience. I also should say that a large draw for me was the large, friendly and helpful community that supported and shared knowledge around the VMware products; easily the best community with which to be associated.

What made you decide to do the VCDX?

For me the decision was twofold, first because I’ve had the great fortune of working with one of the best consultants I know in Doug Baer, VCDX #19 and second for the shear challenge of obtaining the certification. A natural, underlying part of the equation has always been my love of the technology and interest in understanding how it works at its core. In my current line of work, utilizing the skills and knowledge measured by the VCDX certification is highly relevant and in many ways a validation of those abilities.

How long did it take you to complete the whole VCDX journey?

It’s hard to say exactly when the journey started, as I had wanted to go after it for the last couple of years, but it seemed so far off and I never really got going. In May 2011, I started and then stopped my journey with a failed attempt on the required VCAP-DCA exam which in combination with a heavy load of customer commitments limited my ability to focus on it. Since I wasn’t accustomed to failing an exam, the DCA failure caught me off guard and I needed to regroup. It was then about 6 months later over the 2011 Thanksgiving (US) holiday that I had a little heart-to-heart with myself and decided regardless of the time, effort or success, I was going to go after the VCDX4 before it was updated to version 5. I was leaving too many good designs on the table which I had worked on with vSphere 4 to not try to at least defend one of them. That’s when my real, 6-month journey toward VCDX began. This involved the DCD4 exam in December, the DCA4 exam in January, the VCP5 upgrade and the DCD5 beta in February, the VCDX4 Design and application in March and then the VCDX4 Defense in May. Approximately 6-months start to finish, but ultimately the journey never ends or at least I hope it doesn’t.

What advice would you give to people thinking of pursuing the VCDX accreditation?

My advice to those interested in the VCDX would be to dedicate themselves to the investment of time and resources necessary in the effort. This may mean the setup of a home lab, the time to read product guides, the repetition of product implementation and design, and/or the review of countless blogs and knowledge base articles. But beyond having a sound technical and architectural knowledge it will also require comfort in the spotlight, an ability to present from a white board, a quickness to think on your feet, an ability to envision the big picture design, and an openness to feedback, critique and improvement. With all that said, bottom line for anyone seriously considering it, I would say go for it. You’ll never know what could have been if you don’t try. I believe many will be surprised by what they can accomplish when they focus on a goal like the VCDX.

If you could do the whole VCDX journey again what would you do differently?

I probably would have started it earlier. Overall I felt the execution was successful once I got going, but for me it was just the issue of starting and sticking with it. Beyond that I don’t think I would have changed much.

Life after the VCDX?  How did your company respond?  Was it worth it

In my consulting position, the certifications are very much a part of the role and needed by the company to market, sell and deliver the solutions that we focus on. The certification definitely brought some recognition and accolades. It also provided some instant credibility amongst those in our community. For the most part, I do believe it was worth it mainly because of the challenge it provided to me and the opportunity to do what I love most which is work with the technology, understand the architecture of the products, solve the business problems of my customers, and participate in a community that is passionate about all these same things.


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VCDX Spotlight: Rick Scherer

Name: Rick Scherer

Twitter Handle: @rick_vmwaretips

Blog URL: http://www.vmwaretips.com

Current Employer: EMC

VCDX #: 21

How did you get into using VMware?

I first heard of and started using VMware Workstation in late 1999. I was a UNIX Administrator that was forced to live in a corporate Windows world. Workstation allowed me to have the best of both worlds. After thorough use and testing of the GSX and ESX products, by 2003 I was able to convince my (then employers) management that virtualization was a must for our datacenter. The rest is history.

What made you decide to do the VCDX?

Since day one I’ve been convinced that virtualization was a huge benefit for organizations large and small. Obtaining my first VCP (VCP2 #7315) in 2006 I’ve been following the work of the education team closely. When I was invited to be a beta participant in the then newly created VCDX program I saw it as an opportunity to validate my dedication, knowledge and experience. By making a candidate jump through as many hurdles that the VCDX program has, it really shows that VMware users are dedicated to the cause. This is a great way to give VMware additional validation to the industry.

How long did it take you to complete the whole VCDX journey?

From start to finish, an extremely long year, it was extremely rewarding being part of the beta program process though. Being able to assist in the shaping of the program, how the Design and Administration exams were written was really fun.

What advice would you give to people thinking of pursuing the VCDX accreditation?

Know your stuff, inside and out. The VCDX is really a mixture of everything, knowing not only how to fully design and architect a virtualized infrastructure (not only from a VMware perspective but the associated compute, network and storage), but also how to implement that design, manage that design, upgrade that design and operate that design.

Get as much hands on as possible. Learn as much as possible about how compute, network and storage relate to virtualization. Learn how applications relate to virtual machines. Know your design. That’s probably the most important thing, for your defense do not design your dream architecture, keep it simple and keep it to something you’ve done before. Know it inside and out, know what failed and how you fixed it. Don’t say you designed a specific thing to meet Best Practices, know why it’s the best practice.

Also, if you’re married… get your spouse’s buy-in on the journey as well. You’re going to spend a lot of time away from them while you’re on the journey and you’ll need more support than you’ve ever needed before.

If you could do the whole VCDX journey again what would you do differently?

No regrets, I loved every single part of the process. I wish I didn’t rush through it as fast as I possibly did, but I was so excited to be part of something new, something fresh and something fun! How awesome is it to be VCDX #21! J

Life after the VCDX?  How did your company respond?  Was it worth it?

I think obtaining the VCDX certification opened a lot of new doors and opportunities. Since obtaining my VCDX I’ve joined EMC as part of their vSpecialist organization, here I’m able to put my knowledge and experience directly to use as I evangelize companies about all of the amazing benefits of virtualization, application modernization, end-user computing and now cloud computing.


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VMware vSphere Data Protection

vSphere Data Protection (VDP) is a robust, simple-to-deploy, disk-based backup and recovery solution. VDP is fully integrated with VMware vCenter Server and enables centralized and efficient management of backup jobs while storing backups in de-duplicated destination storage.

Benefits:

•VDP leverages VMware vSphere API for Data Protection (VADP) which includes Changed Block Tracking (CBT) along with the EMC Avamar variable-length segment de-duplication engine to optimize backup and recovery times. Initial backups take a fair amount of time, but subsequent backups can be as little as a few minutes depending on the number of changes that have occurred since the last backup.

•Backup agents are not needed as VDP leverages VADP. VMs are backed up to disk-based storage (.vmdk files attached to the VDP virtual appliance).

•De-duplication occurs not only within each VM, but across all backups jobs and all VMs being backed up by the VDP appliance.

•A VM that utilizes an agent for backup and recovery require the VM to be in a powered on state. With VDP, that is not the case – backups and recoveries can be performed regardless of the VM’s power state.

•The is no need to install backup management software on an administrator’s workstation. Configuration and management of VDP is web browser based. Currently supported browsers: IE 7, 8 on Windows. Firefox 3.6 and higher on Windows or Linux. Adobe Flash is required.

•Restores can be entire VM or individual files and folders/directories. The file-level restore user interface (UI) is web based, simple, and intuitive meaning end-users can perform self-service file-level restores (administrator permissions required).

•Deployment, configuration and management of VDP is done via a web browser based graphical user interface (GUI). The majority of configuration tasks are completed using intuitive wizard-driven workflows.

vSphere Data Protection Key Components

VDP VM Appliance

•VDP is a virtual machine appliance deployed from a .ova (open virtual appliance or application) file.

vSphere Infrastructure

•vSphere API for Data Protection (VADP) is utilized by VDP. This includes the Changed Block Tracking (CBT) mechanism. CBT tracks the changes made to a VM at the block level and provides this information to VDP so that only changed blocks are backed up. This significantly reduces storage consumption and speeds up backup and recovery times with VDP.

•VMware Tools on Windows contains Volume Shadow Copy Service (VSS) components to assist with guest OS and application quiescing when backing up Windows VMs. More details on VSS can be found here: http://technet.microsoft.com/en-us/library/ee923636(v=WS.10).aspx

VDP Architecture

•The appliance is deployed by default with 4 vCPUs and 4 GB RAM.

•Available in three sizes: 5 TB, 1 TB, and 2 TB – these are usable destination datastore sizes. The actual amount of disk space (thick provisioned) consumed by the appliance is 850 GB (3 .vmdk files), 1600 GB (7 .vmdk files), and 3100 GB (13 .vmdk files) respectively. Thin provisioning can be used, but the administrator should closely monitor disk consumption. It is important to note that once the VDP appliance is deployed, the size cannot be changed.

•The VDP appliance guest OS is SuSE Linux 11.

•vCenter Server 5.1 is required to use VDP. VDP can backup VMs on hosts running vSphere 4.0 and higher.

•VDP management is done via the vSphere Web Client. There is no plug-in for the vCenter Server “thick” client.

 


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vSphere 5.1 Announced with Enhanced vSphere Replication

vSphere Replication

vSphere Replication (VR) is the industry’s first and only genuinely hypervisor-level replication engine.

It is a feature first introduced with Site Recovery Manager 5.0 to allow for the vSphere platform to protect virtual machines natively by copying their disk files to another location where they are ready to be recovered.

VR is a software based replication engine that works at the host level rather than the array level.

Identical hardware is not required between sites, and in fact customers can run their VMs on any type of storage they choose at their site – even local storage on the vSphere hosts, and VR will still work.

It provides simple and cost-efficient replication of applications to a failover site

VR is a component delivered with vSphere editions of Essentials Plus and above, and also comes bundled with Site Recovery Manager. This offers protection and simple recoverability to the vast majority of VMware customers without extra cost.

•With VR, a virtual machine is replicated by components of the hypervisor, removing any dependency on the underlying storage, and without the need for storage-level replication.

•VMs can be replicated between *any* type of storage platform: Replicate between VMFS and NFS, from iSCSI to local disk. Because VR works above the storage layer it can replicated independently of the file systems. (It will not, however, work with physical RDMs.)

•Replication is controlled as a property of the VM itself and its VMDKs, eliminating the need to configure storage any differently or to impose constraints on storage layout or management. If the VM is changed or migrated then the policy for replication will follow the VM.

•VR creates a “shadow VM” at the recovery side, then populates the VM’s data through replication of changed data.

•While VR can be deployed through the “thick client” all management and interaction with VR is done strictly through the vCenter 5.1 web interface.

•Only vSphere 5.0 and 5.1 will work for vSphere Replication as the VR Agent is a component of the vSphere 5.x hypervisor.

•vSphere Replication can not co-exist with the vSphere Replication pieces originally shipped with SRM 5.0. If an existing SRM 5.0 vSphere Replication environment is in place it will need to be uninstalled and replaced with the standalone vSphere Replication from vSphere 5.1.

•While both Storage DRS and sVmotion are supported, they will cause certain scenarios to be aware of

•While Storage vMotion of a VR protected VM can be done by an administrator, on vSphere 5.0 this may create a “full sync” scenario in which a VM must be completely resynchronized between source and destination, possibly violating the configured recovery point objective for that VM.

•Storage DRS compounds this problem by automating storage vMotion, and thereby may potentially cause the protected virtual machines to create continual full sync scenarios, driving up I/O on the storage, thereby creating cyclical storage DRS events. Because of this it is unsupported with 5.0.

•Storage vMotion and SDRS are only able to be run on the *protected* VM and can not execute against the *replica* of the VM.

•When using vSphere Replication with Site Recovery Manager, storage vMotion and storage DRS are *not supported*

•Neither of these scenarios is true with vSphere 5.1 as the persistent state file that contains current replication data is migrated along with the rest of the VM, which did not occur in vSphere 5.0.

vSphere Replication is not “new” as it has more than a year-long track record of success with Site Recovery Manager.

VR is a non-disruptive technology: It does not use vSphere file-system snapshots nor impact the execution of the VM in any abnormal way.

Since VR tracks changes at a sub-VM level, but above the file system, it is completely transparent to the VM unless Microsoft Volume Snapshot Service is being used to make the VM quiescent. Even then VR uses fully standard VSS calls to the Microsoft operating system.

Virtual machines can be replicated irrespective of underlying storage type • Can use local disk, SAN, NFS, and VSA
• Enables replication between heterogeneous datastores
• Replication is managed as a property of a virtual machine

• Efficient replication minimizes impact on VM workloads

vSphere Replication Use Cases

Protecting VMs within a site, between sites, or to and from remote and branch offices.

Can use dissimilar storage, low cost NAS Appliances, even independent vSphere hosts with only local disk.

VR Deployment

VR is deployed via a standard virtual appliance OVF format.

The OVF contains all the necessary components for VR.

•What used to be both the “VRMS and VRS” in the SRM 5.0 implementation of VR are included in the “VR Appliance” now

•This allows a single appliance to act in both a VR management capacity and as the recipient of changed blocks

•Scaling sites is an easy task, simply deploy another VR Appliance at the target site and it will contain the necessary pieces to either pair and mange replication for a site or simply receive changed blocks as per the VRS

vSphere Replication Limitations

vSphere Replication is targeted at replicating the virtual disks of powered on virtual machines only. It is based on a disk filter to track changes that pass through it, therefore static images can not be tracked.

Powered-off or suspended VMs will not be replicated. The assumption is that if the VM is important enough for protection, it is powered on.

That also means non-disks attached to a VM (ISOs, floppy images, etc) are not replicated. Also any disks, ISOs, or configuration files not associated with a VM will not be replicated.

Files that moreover are not required for the VM to restart (e.g., vswp files or log files) are not replicated by VR.

Since VR works above the disk itself at the virtual device layer, it can be completely independent of specifics about the VMDK it is replicating. VR can replicate to a different format than its primary disk – i.e. you can replicate a thick provisioned disk to be a thin provisioned replica.

VM snapshots in and of themselves are not replicated but instead are collapsed during replication. A VM with snapshots may be configured for protection by VR (and you can take and revert snapshots), but the remote state for such VMs will be “flat” without any snapshots. Snapshots are aggregated into a single VMDK at the recovery location.

Note: Reverting from a snapshot may cause a full sync!

VMs can be replicated with a recovery point objective (RPO) of at most 15 minutes and at least 24 hours. This means that a recovery of replicated VMs will lose at least 15 minutes worth of recent data.

How it works

Fundamentally VR is a handful of virtual appliances that allow the vSphere kernel to identify and replicate changed blocks between sites. The configuration and deployment is a handful of simple steps.

Once the administrator has deployed the components it is a matter of pairing a source and destination.

Lastly, configuration of an individual VM for protection tells VR to start replicating its changes, and where to put them at the recovery location.

Only replicates changed blocks

On an ongoing basis, after the first sync, VR will only ship changed blocks.

Within the RPO defined by the administrator, VR tracks which blocks are being dirtied and will create a “lightweight delta” (LWD) bundle of data to be transferred to the remote site.

Pointers to changed blocks are kept in both a memory bitmap as well as a “persistent state file” (psf) located in the directory of a VM. Memory contents are always current, the PSF file represents the current shipping LWD. After an LWD is shipped and completely acknowledgd, the memory bitmap is copied to the PSF file and the memory bitmap is restarted for the next LWD.

VR will use the defined RPO to determine how often to create a LWD. Time must be allowed to create the block bundle, transfer it, and successfully complete writing the entire bundle to ensure that the RPO is not violated. In order to do this, VR will track the length of the previous 15 transfers to create an estimate of how long it will take to complete the transaction of the subsequent LWD.

For example, if a transfer takes 1 minute to create, 8 minutes to transfer, and 1 minute to write, by the time the data is successfully written the original VM is now 10 minutes old. With, for example, a 1 hour RPO set for a VM, the next transfer would need to take place at least within the next 40 minutes. This presumes 10 minute old data plus the next 10 minute transfer = 20 minutes gone out of the 1 hour RPO to ensure the data at the recovery site is never older than the RPO defined.

If a transfer of a LWD takes more than half the time of the RPO it is very likely that the RPO will be violated based on the incremental “catch up” to the RPO period and it will be flagged as a potential RPO violation.

VR will create a per-host replication schedule by taking into account *all* the VMs being replicated from that particular host. This allows it to do host-wide scheduling for each replicated VMDK and allows transfers to take place according to variables such as length of transfer, size of LWD, etc. and gives the scheduler flexibility to send data when appropriate.

The scheduler will execute each time an event occurs that alters replication patterns, such as a power task on a replicated VM, changes to RPOs or a full sync, or an HA event such as a host crash.

Only the most-recent transfer information is persisted. If hostd crashes, or the VM is migrated, or reconfigured, the historic transfer state is lost, and must be re-accumulated for the scheduler to be most effective.

It is important to note that VR is *not* using vSphere based snapshots to create redo logs of the primary VMDK. The VMDK is not interrupted in any fashion at all, and there is no snapshot created.

It also does NOT use “CBT” or “Changed Block Tracking”, another feature of the vSphere Platform. The vSCSI filter of VR is completely independent of CBT by design. This allows CBT to remain untouched for other tools such as VADP and backup software. If CBT were to be used it would reset the changed block tracking epoch, breaking backups and other uses of CBT.

VR is 100% isolated from snapshots and CBT.

Recovering a VM with a few clicks

A VM can be recovered only if it is not powered on somewhere else or is not reachable by the recovery vCenter Server. This is to avoid having duplicate VMs running at the same time.

For further safety, the VM is booted with no networks connected to help avoid duplicate VMs colliding.

Once the recovery is processed, you can not reconnect and re-enable replication of that VM. You must re-start protection all over again. You may, however, use the old VMDK that might remain at either site as a seed to begin replication again.

Four steps for full recovery

As long as the replication has completed at least once a VM can be recovered quickly and easily directly from the vCenter Web Client.

From the Replication location in the Web Client, choose a VM that has been replicated, right-click and choose to recover.

Choosing a target folder and resource (Cluster, host, or resource pool) will then instantiate the replicated vm, create and register the vmx, attach the VMDK and power-on the VM if chosen.

This can not be automated, and can only be done a single VM at a time.