Category Archives: VCAP

vCD SP 8.10 New Features Part 3 – Storage Tiering and Storage Management

vCloud Director SP 8.10 has been out for a couple months now and the general buzz around this release has been extremely positive. The decision to expose the previously API only features has been warmly welcomed by most vCloud Air Network Service Providers and I have heard of quiet a few looking to deploy or plan deployment of vCD SP 8.10 into their hosting platforms.

In Part One I went through the new NSX supportability improvements and in Part Two I went through the tenant ability to configure VM affinity and anti-affinity rules. In Part Three I am going to go through something that’s been available via the API since vCD 5.6.3 SP but is now exposed via the UI and also take a look at a new feature around the limiting of the max size of a tenant VMDKs in a vCD environment.

  • VM Disk Level Storage Profiles – Allows a single virtual machine (VM) to access different tiers of storage such as storage area network (SAN), network-attached storage (NAS), and local storage to help balance storage cost vs. storage performance. VMware vCloud Director 5.6 also supports VMware Virtual SAN.

Fast Provisioning:

Before showing the new UI Storage Profile features it’s worth mentioning that this will not work if you have vDCs configured with fast provisioning enabled. If you try to configure multiple profiles against a VM you will get a “Cannot use multiple storage profiles in a fast-provisioned VDC” error message.

Fast provisioning was introduced with vCloud Director 1.5 and enables speeding up a cloning process when deploying vApps from catalog or copying VMs. It utilizes vSphere linked clones where the base image is not cloned, instead a delta disk is created to record changed blocks.

Great in theory, but also carries some caveats…not allowing VM Disk level storage profiles being one of them. If turned on, head to the Storage Tab of the vDC and uncheck the option as shown below.

VM Disk Level Storage Profiles:

There isn’t a lot that needs explaining in terms of what can now be achieved through the UI to better provision and manage different storage requirements on a per VM disk basis. vCD Storage Profiles directly plug into vCenter Storage Policies and inherit the characteristics passed through from vCenter into vCD via the Provider vDC. These are then allocated to vDCs as shown in the image above. Generally speaking these policies map back to different tiers of storage and allow the Service Provider to offering different service levels at different price points.

As an example a tenant may have a requirement to have a large file server that doubles as a Domain Controller (it happens more than you think) for the System drive the requirements might state that you need SAS backed storage and SATA backed for a secondary volume. This can now be achieved through the vCD UI as shown below.

You can see above that Disk 0 is on ioSTOR-500 and Disk 1 is on ioSTOR-250. The example above is for the adding of new disks to a VM…you can also change the Storage Profile while a VM is on. This will trigger a Storage vMotion in the background if required as shown below.

Limiting Maximum Disk Size:

There are some scenarios where a Service Providers might want to limit the max size of tenant VMDKs in order to comply with capacity planning requirements or storage level constraints. The current max size for a VMDK in vSphere is 62TB and being realistic there are not too many Service Providers out there who provision datastores that size. Typically, the storage limits applied at an allocation pool should limit the creation of stupidly large disks by tenants, but there is the possibility that someone with deep pockets purchasing large amounts of storage could try to provision a VM (thin or not) Disk larger than the datastores underpinning the storage policy.

To set the global disk limit you use the cell-management-tool command on any vCD cell in the instance. Once run the value is honors immediately and without restart of the vCD services as shown in the example below that limits the disks to 500GB.

./cell-management-tool manage-config -n vmlimits.disk.capacity.maxMb -v 500000

Once configured, if a tenant tries to provision a disk bigger than the limit they will get an error stating that the “Requested disk size exceeds maximum allowed capacity“.


Attention IT Recruiters – VCDX | VCIX | VCAP | VCP – Letters That Add Value!

There has been some discussion in the vExpert Slack channel over the last couple of days discussing how the vExpert Program which is an advocacy program that VMware awards to engaged members of the community was more recognized than actual VMware based certifications including the coveted VCDX. Without diminishing the value of the vExpert Program, this has been discussed in many circles for a while now and generally revolves around the fact the the VCAP exams are almost non existent when it comes to desirable certifications on resumes. Even the VCDX seems to be generally relegated to a “Explain what a VCDX is and aren’t vExperts the Virtulization Experts of choice?” conversation.

Within the VMware community we know and understand exactly when it means to achieve a VCP. We know the step up and the experience required to achieve VCAPs and VCIXs and many know the absolute effort and commitment it takes to persue and gain a VCDX. While the VCP can be achieved via braindumps the consensus is that the VCP 5 and 6 versions are no walk in the park. VCAPs and VCIX administration and design exams can’t be braindumped and to pass those exams shows advanced skills with VMware products. The VCDX is a whole different level and in addition to having to pass VCPs, at least two VCAPs/VCIXs successful candidates go through hundreds of hours of design documentation before sitting a defence in which candidates are put under immense pressure to be able to get enough points to become a VCDX…a master of architectural design and thinking.

So whats the problem here and why are these certifications not as well known and recognized as they should be? It’s apparent that there needs to be more education in the Tech HR and Recruitment space that goes some way to having these certs (and other industry certs) recognized more and have their true value understood. In addition to that IT managers who do the employing need to understand what each exam gets you in terms of the candidate filling a role.

How this is achieved I am not sure but maybe IT recruiters will stumble across this post and use it as a springboard to better understand the certifications listed above. It’s also up to the hiring manager to start understanding the value by adding them to job descriptions as desired certifications. These exams are not cheap and they represent significant investment in time and effort to pass and as the numbers around the globe show below…these certifications are not gained without effort.

Looking at data below it’s clear to see that with only 220 odd VCDXs, 4000 odd VCAPs and with the number of VCPs similar to the CCIE’s rough 50,000 you can start to see the uniqueness of the VMware certifications. Weather that translates to better skilled employees I can’t answer that and I’m certainly not advocating increased dollar values of potential candidates just because they hold these certifications but the aim here is to increase the understanding of the value that each certification brings.

I’d be interested to hear is this sentiment if felt in other certification areas such as Microsoft, Citrix and in newer areas like AWS and other vendor certifications…feel free to comment below.

VCDX Links:


VCP Links:

Example Certification Path:


VCAP Exam Retirement – Not Well Received…

VMware Education dropped somewhat of a bombshell today when they announced the almost immediate retirement of the VCAP CIA/CID/DTA/DTD

Effective March 2, 2015 the following certification exams will be retired and no new registrations accepted:

  • VCID510 – VMware Certified Advanced Professional 5 – Cloud Infrastructure Design
  • VCIA510 – VMware Certified Advanced Professional 5 – Cloud Infrastructure Administration
  • VDTA510 – VMware Certified Advanced Professional 5 – Desktop Administration
  • VDTD510 – VMware Certified Advanced Professional 5 – Desktop Design

There has already been a fairly big outcry in the VMware Community around the decision to scrap the exams…and even though this move had been expected with the announcements of the new VCIX Advanced Exam Roadmaps, what I think people didn’t expect was the chopping off at the head of these VCAPs. This has left some people’s plans of VCDX defense attempts in limbo…specially for those who where looking to defend for Cloud based on vCloud Director…vCloud Director has been pulled from the vCloud Suite for Enterprise but is still very much alive for Service Providers…I know of a few guys (myself possibly, though not 100% committed) who where already building documentation around vCloud for a defense.

To me I this shows a clear disconnect from the VMware Education and Certification team from what is actually happening in customer and partner land…the way this has been done is a mistake and VMware needs to retract the immediate retirement and put a 3-6 month period of these exams to EOL. There also needs to be some direction as to a roadmap for Service Providers who will continue to use vCD+NSX+VIO who would not be looking at vRealize Automation.

Feel free to comment below on your thoughts around the retirements…hopefully VMware Edu Services will read the communities thoughts and respond with something positive.


VCAP-DCA – Experience

I couple of months ago I wouldn’t have seen myself writing up one of these blog posts which seems to be customary for any blogger who has taken a VCAP. Having only secured my VCP last October I wasn’t thinking about VCAPs until the lure of the 50% discount and realisation that I needed to push myself further. Four weeks before VMworld I decided to accept the challenge and booked the exam for the Sunday at 2pm. Another big driver for me to take the exam at VMworld was that I thought it was means to avoid the dreaded latency that seems to plague takers in Australia.

510 or 550?:

This was an interesting choice for me…it seemed that even with the 550 available most people where choosing the 510. To make up my mind I read through both blueprints and saw that certain sections where missing from the 510 (vMA, Autodeploy) while newer features like vSphere Replication and vFlash Read Cache where added along with vCO. That said when I booked my exam I decided to do the 510, however there where no slots at VMworld so I was forced to book the 550. End of the day I think that that was the right DCA and from what I understand the exam format has been better optimized for takers. I can see how the additional items on the blueprint could put people off, but in reality it shouldn’t be daunting for seasoned vSphere Admins. So end of the day I gave myself just over 3 weeks to prep.

Materials and Study:

Having the Blueprint by your side throughout the prep is critical…know it back to front and use resources out there like Chris Wahls Study Guide to work through the objectives and know what you know…and what you need working on…you really can’t afford to skip any section.

Having had a spare Amazon Voucher I had back ordered the VCAP-DCA Official Study Guide in February without any real intent of taking the DCA any time soon, however having this book allowed me to structure study based on it’s excellent chapter content which follows the 5.1 and 5.5 Blueprint objectives.

Pluralsights pay per the month for all training content is worth its weight in gold and Jason Nash’s Optimize and Scale Course is what I considered to be my most valuable study asset. The offline mode can be consumed anywhere and I spent most train rides and gym sessions working through chapters. I went through the content about 4-5 times in total stepping up the play speed each time…by the end of it I had Jason coming at me in 2x…

I also took the official VMware Optimize and Scale Course 5.1 in October of 2013. While I don’t think it ultimately helped me pass or fail the exam, its still worth a shot if the training expense can be justified.

The Lab:

For me, without a decent lab there is no chance of passing this exam…I am/was lucky in that I have a very decent lab at my disposal through ZettaGrid, but I still loaded up a mini lab on my Mac Book Pro to help me study and revise while on the plane ride over to VMworld. You need to go over and execute CLI commands because speed is the key in this exam…I would also learn up on 5.5 Web Client menu context and where to configure the new features listed in the Blueprint. A Lab with access to iSCSI/NFS shares is recommended and work through relevant blueprint items again and again…see how I am saying that repetition is key here? ☺

The Exam:

The format has changed fairly significantly from the 500 and 510 exams from my research and in asking others of their experience…You now get 23 questions over 180 minutes and the Exam Lab has five ESXi Hosts, 2 vCenters and a bunch of datastores…you also get a vSphere Replication Appliance and vCO Server instance.

Throughout the exam you are repeatedly warned to not change anything but what actions are stated in the question…Modding the Management Networking in error could end the exam. There seems to be a little more leeway on that and I found out the hard way when I completely misread one question and almost bricked a host..lucky it was a 5.5 host or else my dVS might not have come back.

As expected I didn’t have any issues with Latency and performance of the lab…this was a big thing and meant I could attack questions without the worry of screen refresh issues due to latency or sticky keys for CLI commands.

On that note, time management is absolutely key…I was working on 8 questions an hour, but quickly found the time coming down quick…some questions take longer than others, but I felt each question was roughly equal in terms of whats expected. Two questions stumped me initially and I left them for the end if I had time. I got to the end of question 23 with about 14 minutes left and attempted to go back and answer the 2 that caused me trouble…end of the day I had to leave those unanswered.

When time expired I got the message saying that your results would be sent out in 15-20 days. Overall I left the exam fairly positive I had done more than enough to pass.

The Result and Final Thoughts:

I got a Tweet from SOSTech_WP later in the evening while enjoying the Redwood Room at The Clift saying to check my email…when I got back to the hotel I was extremely surprised to see the results email waiting for me in my inbox. And while I didn’t smash it like I thought I was going to upon coming out…a pass is a pass is a pass! I was relieved and fairly happy that the plan had worked and all the hard work of the previous three weeks had paid off.

In reality it wasn’t just about the last three weeks and this VCAP-DCA exam is a true representation of an acquired skill level in administrating a complex vSphere platform and in that it was a validation of the work I do in and around vSphere. People commented to me prior to taking the exam that it was a fun exam to take…and I certainly understand that point of view… I had a great time taking it…but had a better time passing it!

Next for me is to decide on a more challenging path and journey…certainly one that may have me taking at least one more VCAP Administrator Exam and a Design Exam.

Good luck to all those taking the VCAP-DCA in the future.