Eric Sloof

Here’s a short write-up regarding my VCAP5-DCD exam experience. The training course I was scheduled for this week was cancelled, so I decided to give the VCAP5-DCD exam another try. I already failed for the beta and my first attempt for the regular one but VMware was so kind to provide me with a voucher, which would expire soon.

So besides some household tasks, I’ve used this week for some serious prepping. One of the most important sources for my study was the lecture guide of the VMware vSphere design Workshop. I’ve delivered this training course several times and it has some great content. Especially the first chapters where the different types of design stages like logical and conceptual are well explained. They definitely need some extra attention. You have to know what happens at each specific stage.

Also take a very good look at this diagram, which explains abbreviations like RTO, RPO and MTPOD. Source (http://www.goh-moh-heng.com/wp-content/uploads/defining-RTO.png)

Before starting at a design question write down the number 1,2,3,4 or 5 and the time you’ve started designing. Don’t jump into Visio-mode, I nearly blew one by connecting the connectors to the wrong objects. Read the assignment well enough to be able to complete the lab. It is a myth that the design questions don’t count for your final score. They are responsible for a significant part of your end score, so take them serious. 

The drag and drop questions are sometimes a bit lengthy, but don’t skim the text. There are very important details hidden in it so read it fully. The other “multiple choice” and “choose all that apply” questions are not that hard. It’s the knowledge that you already posses that will get you through. Just think straight but don’t answer too fast and click next, because you can’t go back.

I finished the exam with only 3 seconds on the clock left. My end score was 338. I must admit, I had the feeling I did a bit better and would end-up near 400 points, but a pass is a pass. Good luck with your VCAP-DCD.

Apache Hadoop provides a platform for building distributed systems for massive data storage and analysis using a large cluster of standard x86-based servers. It uses data replication across hosts and racks of hosts to protect against individual disk, host, and even rack failures. A job scheduler can be used to run multiple jobs of different sizes simultaneously, which helps to maintain a high level of resource utilization. Given the built-in reliability and workload consolidation features of Hadoop it might appear there is little need to virtualize it. 

However, there are several use-cases that make virtualization of this workload compelling:

• Enhanced availability with capabilities like VMware High Availability and Fault Tolerance. The performance implications of protecting the Hadoop master daemons with FT were examined in a previous paper.
• Easier deployment with vSphere tools or Serengeti, leading to easier and faster datacenter management.
• Sharing resources with other Hadoop clusters or completely different applications, for better datacenter utilization.
  
  

In addition, virtualization enables new ways of integrating Hadoop workloads into the datacenter:

 

• Elasticity enables the ability to quickly grow a cluster as needs warrant, and to shrink it just as quickly in order to release resources to other applications.
• Multi-tenancy allows multiple virtual clusters to share a physical cluster while maintaining the highest levels of isolation between them.
• Greater security within each cluster as well as elasticity (the ability to quickly resize a cluster) require the separation of the computational (TaskTracker) and data (DataNode) parts of Hadoop into separate machines. However, data locality (and thus performance) requires them to be on the same physical host, leading to the use of virtual machines.
  
  

Nimble Storage fully integrates with VMware SRM to automate DR protection, test and recovery for the storage layer. Major points of integration between VMware vCenter Site Recovery Manager and the Nimble Storage Arrays are done via a “Storage Replication Adapater” (SRA) written by Nimble to the specifications provided by VMware. The SRA allows for a number of storage interaction workflows to be initiated from Site Recovery Manager, such as: Discovery; Test Failover; Cleanup; Planned Migration; Disaster Recovery; Reprotect.

The SRA helps SRM discover Virtual Machine File System (VMFS) datastores that are configured with cross-site replication. Arrays are pre-configured with replicated devices or consistency groups, which are then presented to the vSphere clusters. In the SRM server the SRA must be installed to allow visibility to these replicated devices. After the SRA is installed and configured, replicated devices are represented within SRM, available for use in workflows.

VMware Education is about to release a new training course called "VMware vCloud Networking and Security for vSphere Professionals". This intensive training course focuses on installing, configuring, and managing VMware vCloud Networking and Security for the VMware vSphere professional. vCloud Networking and Security is a suite of security virtual appliances built for VMware vCenter Server and VMware ESXi integration. 

vCloud Networking and Security is a critical security component for protecting virtualized datacenters from attacks and helping you achieve your compliance-mandated goals. The course is based on ESXi 5.1 and vCenter Server 5.1.