This is the 7th part of my VCAP7-DTM Design exam series. In part 6 I covered the creation of a physical network design for Horizon 7. This time we take a look at section 6 of the blueprint, the creation of a physical design for Horizon desktop and pools:
Section 6 – Create a Physical Design for Horizon Desktops and Pools
Objective 6.1 – Design Virtual and Physical Image Masters
Objective 6.2 – Optimize Desktop Images, OS Services and Applications for a Horizon Design
Objective 6.3 – Incorporate Desktop Pools into a Horizon Design
Objective 6.4 – Incorporate RDS Pools into a Horizon Design
The desktops your customer provides must satisfy the use case requirements to ensure a good user experience and user acceptance. To provide desktops with Horizon you have to create so called desktop pools. VMware has a few recommendations and leading practices for the configuration and optimization of a Horizon desktop. These things will help you to enhance the overall scalability and performance of a Horizon implemenation.
The desktop build process would look like this:
You will start with the creation of the target VM
Installation of guest OS
Installation of VMware Tools
Perform image optimization
Installation of globally used applications and Horizon Agent
Creation of VM template
If you understand the customer’s use cases, you will understand what kind of desktops are needed to meet the requirements. The configuration of the desktop VM varies for each pool. The differences between them are often resource allocations like disk size, installed applications, memory or even the operating system.
For the most use cases VMware recommends only assigning two vCPUs unless it’s proven and really a requirement to have more CPU power.
Consider RAM reservation settings and keep in mind that high memory settings require more disk space as the VM swap file and the Windows pagefile sizes are related to these settings.
Globally used applications like MS Office or Adobe Reader should be installed within the desktop image. All other applications are delivered with App Volumes, if possible.
VMware recommends optimizing the guest operating system of a desktop image to positively affect the performance of a Horizon desktop.
Use VMware OS Optimization Tool (OSOT) to optimize your Windows desktops and server images. It is a great tool and will help you to disable OS components you don’t need and could help to enhance the overall scalability and performance. Make sure you know the optimizations you apply and what settings are changed to avoid any bad user experience or unexpected behaviour of your desktops.
If you are using Windows 10 for example, also make sure that you remove all unneeded native apps.
You can create desktop pools to give users remote access to virtual machine-based desktops. You can also choose VMware PC-over-IP (PCoIP), or VMware Blast to provide remote access to users.
There are two main types of virtual desktop pools. Automated desktop pools use a vCenter Server virtual machine template or snapshot to create a pool of identical virtual machines. Manual desktop pools are a collection of existing vCenter Server virtual machines, physical computers, or third-party virtual machines. In automated or manual pools, each machine is available for one user to access remotely at a time.
With Horizon 7.5 a instance is limited to 10’000 desktops and if the planned deployment exceeds this limit, then you must use the Cloud Pod Architecture (CPA) feature. With CPA you can link together 25 pods to provide one big desktop environment for ten geographically distant sites and provide apps and desktops for up to 200’000 sessions. See VMware Horizon 7 sizing limits and recommendations.
In a Horizon design you must state the use cases and use desktop pools which are the logical containers that represent each use case (desktop type, application set, access mode etc.).
With VMware Horizon it is also possible to provide hosted applications with the integration or Remote Desktop Services Hosts (RDSH) based on Microsoft Remote Desktop Services (RDS).
A RDS desktop pool is associated with a farm, which is nothing more than group of RDS hosts. Each RDS host is a Windows Server that can host multiple RDS desktop sessions.
The Horizon 7.5 handbook is a really great source for this part and I will allow myself to copy and past some part of it. 🙂
There are two options for a desktop assignment:
Each user is assigned a particular remote desktop and returns to the same desktop at each login. Dedicated assignment pools require a one-to-one desktop-to-user relationship. For example, a pool of 100 desktops are needed for a group of 100 users.
Using floating-assignment pools also allows you to create a pool of
desktops that can be used by shifts of users. For example, a pool of 100 desktops could be used by 300 users if they worked in shifts of 100 users at a time. The remote desktop is optionally deleted and re-created after each use, offering a highly controlled environment.
This means that a floating assignment is recommended because it decouples the user from a specific desktop and provides management and resource efficiency. This obviously could also reduce the licensing costs.
Dedicated desktop assignments are useful or required where users have applications or data that they install and keep on a specific desktop. A dedicated desktop can be assigned (fixed) to a specific user or also during the first logon where the next unused desktop will be assigned automatically.
Full Clones, Linked Clones or Instant Clones?
One of the most important questions for your design is whether users need a stateful or stateless desktop to work with. If the user has a stateful desktop, you have to think about the data which needs to be included in a backup (e.g. user profile or application data).
If you provide stateless desktop images you face other challenges. What happens to a user’s profile or data? Should it be saved and be available in the next session?
Stateless desktop images
Also known as nonpersistent desktops, stateless architectures have many advantages, such as being easier to support and having lower storage costs. Other benefits include a limited need to back up the virtual machines and easier, less expensive disaster recovery and business continuity options.
Stateful desktop images
Also known as persistent desktops, these images might require traditional image management techniques. Stateful images can have low storage costs in conjunction with certain storage system technologies. Backup and recovery technologies such as VMware Site Recovery Manager are important when considering strategies for backup, disaster recovery, and business continuity.
There are two ways to create stateless (non-persistent) desktop images in Horizon 7:
You can create floating assignment pools or dedicated assignment pools of instant clone virtual machines. Folder redirection and roaming profiles can optionally be used to store user data.
You can use View Composer to create floating or dedicated assignment pools of linked clone virtual machines. Folder redirection and roaming profiles can optionally be used to store user data or configure persistent disks to persist user data.
There are several ways to create stateful (persistent) desktop images in Horizon 7:
You can create full clones or full virtual machines. Some storage vendors have cost-effective storage solutions for full clones. These vendors often have their own best practices and provisioning utilities. Using one of these vendors might require that you create a manual dedicated-assignment pool.
You can create pools of instant-clone or linked-clone virtual machines and use App Volumes user writable volumes to attach user data and user-installed apps.
Whether you use stateless or stateful desktops depends on the specific type of worker.
There could be a lot more to tell you about when creating desktop pools, but those details can be found on Tech Zone and the available PDFs and Youtube videos.
The next time we take a look at “Section 7 – Incorporate Application Services into a Horizon Physical Design”.
This is the sixth part of my VCAP7-DTM Design exam series. In part 5 I covered the creation of a physical design for horizon storage. This time we take a look at section 5 of the blueprint, the creation of a physical network design for Horizon:
Section 5 – Create a Physical Design for Horizon Networking
Objective 5.1 – Plan and Design Network Requirements for Horizon solutions (including Mirage and Workspace One)
Objective 5.2 – Design Network and Security Components Based on Capacity and Availability Requirements
Objective 5.3 – Evaluate GPO and Display Protocol Tuning Options Based on Bandwidth and Connection Limits
Networking is also a very important and exciting when creating a Horizon architecture and a lot of questions are coming up when I think about Horizon and network access and devices:
How does the ISP infrastructure look like?
Do we have redundant internet uplinks?
Bandwidth in the data center?
How is the connection between Horizon client and agent?
ESXi host network interfaces?
Do we have mobile workers using WLAN?
I once had a customer who had a really nice and modern data center infrastructure, but their firewalls didn’t provide enough throughput. Make your homework and know how the routing and switching looks like and check every component’s limit.
Beside our VDI traffic, what about management, vMotion and vSAN traffic? Do we have enough network interfaces and bandwidth? If you think about management traffic, then 1Gbit interfaces are normally sufficient. But vMotion and vSAN traffic should have redundant 10Gbit connections and be on different subnets/VLANs.
Overview of the Network Architecture
In most network architectures two firewalls exist to create the DMZ.
The Unified Access Gateway (UAG) appliances are placed in the DMZ. UAG can perform authentication or pass a connection to the Connection Server for AD authentication.
Notauthenticated sessions are dropped at the Unified Access Gateway appliance and only authenticated sessions are allowed to connect to the internal resources.
UAG appliances in the DMZ communicate with the Connection Server instances inside the corporate firewalls and ensure that only the desired remote apps and desktop sessions can enter the corporate data center on behalf of this strongly authenticated user.
Inside the corporate firewall you install and configure at least two Connection Server instances. Their configuration data is stored in an embedded LDAP directory (AD LDS) and is replicated among all members of the group.
The used session bandwidth between the Horizon client and agent depends highly on the session configuration. For display traffic, many elements can affect network bandwidth, such as the used protocol, monitor resolution, frames per second, graphically intense applications or videos, image and video quality settings.
Because the effects of each configuration can vary widely, it’s recommended to monitor the session bandwidth consumption as part of a pilot. Try to figure out the bandwidth requirements for each use case.
I would say that Blast Extreme is the way to go, because it has been optimized for mobile devices and can intelligently switch between UDP and TCP (Adaptive Transport). PCoIP has been developed by Teradici, but Blast is VMware’s own creation and that’s why I think that Blast will be “the future” and that RDP still can be used as fallback for some special scenarios.
Display Protocol Tuning Options
I will not cover this topic and explain you how you can configure the maximum bandwidth for PCoIP via GPO. There are several options to decrease and increase the used session bandwidth:
Nowadays, every client device is connected with 1Gbps. LAN connections and the user experience are most of the time perfect. How is it with WAN connections where you will have latencies that could be between 50 and 200ms? Do you apply Quality of Services (Qos) policies to prioritize Horizon traffic?
WAN optimization is one of the keywords when talking about WAN connections and is valuable for TCP-based protocols which require many handshakes between client and server, such as RDP.
PCoIP is UDP-based and this was the reason why everyone in the past said, that you should prefer this protocol for connections with higher latencies and then no WAN optimization or acceleration would be needed.
Then inside the corporate network you would use RDP because your network is stable or did you leave this choice to the user?
With Blast Extreme, Adaptive Transport will automatically detect higher latencies and automatically switches between TCP and UDP if needed. Higher latencies could also occur with mobile devices working of WiFi networks.
In my opinion there are almost no reasons anymore to use anything else than Blast because it’s also more network efficient than PCoIP.
Use separate networks for vSphere management, VM connectivity, vMotion and vSAN traffic. Make sure you have redundancy across different physical adapters (NIC, PCI slot) and devices (switches, router, firewall). Consider the use of a vSphere Distributed Switch (vDS) to reduce management overhead and provide a richer feature set. Maybe NSX could be interesting for micro segmentation.
Load balancing is a very important component of a Horizon architecture. The primary purpose of load balancing is to optimize performance by evenly distributing client sessions across all available Connection Server instances. The same is valid for UAG appliances, Identity Manager or App Volumes Manager. NSX comes with a virtual load balancer, but F5 and NetScaler are also fine.
Depending on your customer’s requirements and needs, the network design is another key part to remove single point of failures.
In part 7 we will figure out how we have to design Horizon desktops and pools.
This is the fifth part of my VCAP7-DTM Design exam series. In part 4 I covered the creation of a physical design for vSphere and Horizon components. This time we take a look at section 4 of the blueprint, the creation of a physical design for horizon storage:
Section 4 – Create a Physical Design for Horizon Storage
Objective 4.1 – Create and Optimize a Physical Design for Horizon Infrastructure Storage
Objective 4.2 – Create and Optimize a Physical Design for View Pool Storage
Objective 4.3 – Create and Optimize a Physical Storage Design for Applications
Objective 4.4 – Create and Optimize a Tiered Physical Horizon Storage Design
Objective 4.5 – Integrate Virtual SAN into a Horizon Design
This article is not a comparison between HCI and traditional storage architecture and if you build hosts by yourself or buy Dell EMC’s VxRail or any other vSAN ReadyNode.
Since it is VMware’s strategy to push vSAN and get away from traditional storage, I only cover vSAN. For my VCDX design I will also move away from traditional storage and use vSAN – it’s also my customer’s strategy. The price for flash storage is decreasing constantly and makes a hybrid vSAN architecture less attractive – at least for our use cases.
In general the storage design of a Horizon implementation is very critical. You have to think about capacity, growth capacity, data/object placement, disaster recovery, kind of SSD disks and so on. But in my opinion, HCI or vSAN makes your life a lot easier and simplifies the storage deployment.
If you fail to correctly size the storage and I/O capacity, your customer’s user experience will suffer or the deployment of new desktops is not possible anymore. So, storage performance and sizing is vital for the satisfactory of your customers and their users!
All-Flash or Hybrid Architecture
The first thing you have to figure out and define is the vSAN platform you are going to deploy – All-Flash or hybrid architecture. A All-Flash vSAN configuration aims at delivering very high IOPS with low latencies. Also in a All-Flash configuration you use two different grades of (flash) disks: lower capacity and higher endurance device for the capacity tier and more cost-effective and higher capacity disks for the capacity tier
There is no read cache available in a All-Flash configuration as all data is directly read from the capacity tier. Because you aim for extremely high IOPS, make sure you provide a dedicated 10Gb network for the vSAN traffic.
You can enable the deduplication and compression setting (not available when using a hybrid vSAN) in the vSAN cluster to reduce redundant copies of blocks within the same disk group to one copy and to compress the blocks after they have been deduplicated.
Erasure Coding (RAID 5/6 is only available with All-Flash) provides the same level of redundancy as mirroring, but with a reduced capacity requirement. In general, erasure coding means breaking data into multiple pieces and spread them across multiple devices, while adding parity data in the event data gets corrupted or lost. This is a good and short video about this feature:
When using vSAN without further adjustments, your virtual desktops and infrastructure servers are using the default vSAN storage policy. For infrastructure servers this might be okay, but for our desktops we need to create a new policies. Cormac Hogan has very good material about Horizon and vSAN Storage Policies:
The Number of Failures to Tolerate defines the number of host, disk or network failures a storage object can tolerate. This number of Failures to Tolerate (FTT) has the greatest impact on your capacity in a vSAN cluster. Based on your configured availability requirements for a VM, the settings in the policy can lead to a higher consumption on the vSAN datastore (more copies of your data). For “n” failures tolerated, n+1 copies of the object are created and 2n+1 hosts are required.
Consider to configure FTT = 0 for the OS disk for linked-clone floating pools or if you use full-clone non-persistent desktops. If vSAN should experience a failure, only non-persistent data will be lost.
I hope this information was helpful even we didn’t go to deep. If you need to know more about vSAN, then you’ll find tons of documents and other blogs about this technology.
In part 6 I’ll try to give you more information about the design for a Horizon network.
This is the fourth part of my VCAP7-DTM Design exam series. In part 3 I covered the creation of a logical design for Horizon 7. This time we take a look at section 3 of the blueprint, the creation of a physical design:
Section 3 – Create a Physical Design for vSphere and Horizon Components Objective 3.1 – Create a Horizon Pod and Block Architecture Design Objective 3.2 – Extend Horizon Architecture Design to Support Additional Horizon Suite Components Objective 3.3 – Design vSphere Infrastructure to Support a Horizon Implementation Objective 3.4 – Add Required Services to Support a Given vSphere Design
Physical diagrams contain more details than the logical architecture and could can brand names or models of storage arrays, network switches and so on. In the physical design we will describe individual parameters or settings for each component.
VMware Horizon Block and Pod Design
A VMware Horizon solution includes one or more Horizon instances, where a Horizon instance is a pod that includes one or more building blocks.
A building block consists of physical servers, a vSphere infrastructure, Horizon 7 servers, shared storage, and virtual machine desktops for end users. A building block is a logical construct and should not be sized for more than 2’000 Horizon desktops. Customers usually include up to five building blocks in a Horizon 7 pod, although in theory you can use more blocks than that, as long as the pod does not go above 10’000 sessions and 7 Horizon Connection Server instances.
The Cloud Pod Architecture (CPA) feature allows you to link multiple Horizon pods together (using the View Inter-Pod API (VAPI) protocol) to provide cross-data center administration and to perform local or global user-to-desktop mappings (entitlements). In a traditional Horizon implementation you manage each pod independently.
There are two different kind of building blocks, the management block (only one) and the resource block (up to 5 in a Horizon pod)
VMware recommends about 2’000 sessions or desktops in a Horizon resource block which includes at least one Horizon Connection Server (CS). In addition to the CS other components like ESXi hosts, vSphere clusters, desktop and application pools and storage form a VMware Horizon resource block.
One Horizon pod can contain up to 10’000 sessions or desktops and 7 Connection Server instances. For environments exceeding the 10’000 users, you have to leverage the Cloud Pod Architecture feature with the usage of load balancers.
In the image above each Horizon 7 resource block has its own vCenter Server. Since View 5.2 and later customers have the ability to use a single vCenter Server instance to manage a 10’000 desktop environment. Although using one vCenter Server for 10’000 desktops is possible and supported, doing so is not recommended because this design creates a single point of failure. The loss of that single vCenter Server prevents any desktop power management, provisioning and other operations.
The Horizon 7 management block consists of the VMs that are supporting the block and pod infrastructure:
vCenter Server instances, Horizon infrastructure servers, Connection Servers, database servers, Composer, UAG, Active Directory, DNS, DHCP, Certification Authorities etc.
Horizon Component Design
To be able to deliver the Horizon 7 services, we first need to design and build the required infrastructure components.
VMware Identity Manager (vIDM) provides the optional WorkspaceONE portal which provides access to different types of applications (Horizon desktop & apps, SaaS-based web apps, ThinApp packaged applications and even Citrix-based application an desktops). Even vIDM is available from on-premises installation, VMware recommends a SaaS-based implementation.
Following VMware’s recommendations, you will need at least three vCenter Server instances:
– 1 vCenter Server for every 2’000 desktops – 1 vCenter Server for the Horizon management block – 1 vCenter Server for the vCenter Server Management cluster (with all vCenter Servers including networking and security instances)
Each Horizon Connection Server provisioned with the minimum supported system specifications should be able to manage the connectivity for up to 2’000 users. If you are using Blast Secure Gateway connections to desktops using HTML access, the Connection Server only can have a maximum of 800 connections. A minimum of two Connection Servers is recommended for failover and redundancy reasons. VMware supports a maximum of seven active Connection Servers per replication group because of Java Message Services (JMS) performance limitations.
Connection servers are active only if they are enabled in Horizon Administrator to accept connections. A disabled connection server communicates with other connection servers in the group and replicates the LDAP directory.
This means that, if you have deployed the maximum of 7 Connection Servers, five have to be enabled and two disabled.
Although View Composer can be installed on the same server as the Windows vCenter Server, for larger environments VMware recommends that you install View Composer on a standalone server. Each Composer server requires a unique Composer database. However, multiple Composer databases can be placed on a single SQL instance. A View Composer server is always paired with a vCenter Server for each Horizon block. If possible, VMware recommends using the Instant Clone technology which doesn’t need additional infrastructure servers.
The Unified Access Gateway (UAG) is the new way to allow remote connections and has the same features like the old View Security Server. The UAG appliance (VM based on Linux) is normally installed in the DMZ and enables secure access from outside the corporate network to the internally hosted desktop and application servers. Unlike a Security Server, the UAG appliance doesn’t need to be paired with a specific Connection Server. VMware recommends the usage of a UAG than Security Server.
This is it. 🙂 The next article focuses on section 4 where the design for Horizon storage is the topic.
This is the third part of my VCAP7-DTM Design exam series. In part 2 I covered the creation of a conceptual design for Horizon 7. This time we take a look at section 2 of the blueprint, the creation of a logical design.
As you already know, the conceptual design or architecture is the one you begin with and is driven by the most essential requirements (the ones you gathered during the assessment). Typically you do not mention any specific solution or product in the conceptual design. To provide more details you will create a logical design of the Horizon solution.
The logical architecture should provide a high-level overview of the proposed architecture for the customer’s Horizon environment and helps all involved people in the early phases of planning, designing and deploying the solution.
As you can see, it now contains components like connection servers, Identity Managers, Composer Servers, database servers etc. The logical diagram shows you more details than before but the more specific (technical) details for each component will be described in the physical design which is part of section 3 of the exam blueprint. Example: Amount of App Volumes Managers Permissions of UEM shares Applied GPOs Load balancing solution
As you may know from the first article, I successfully passed my VCP7-DTM exam and now I’m studying for the VCAP7-DTM Design certification.
Before we take a closer look at the different objectives or requirements, there is one important information about the VCIX7-DTM track. Since no VCAP7-DTM Deploy exam is available and it’s not clear yet when this exam will be published, you only need the VCAP7-DTM Design certification to earn the VCIX7-DTM status. I have got this information from VMware certification.
Section 1 – Create a Horizon Conceptual Design
Let’s have a look at the different objectives from section 1 and see what they mean for me using my learning resources.
Objective 1.1 – Gather and analyze requirements Objective 1.2 – Gather and analyze application requirements Objective 1.3 – Differentiate requirements, risks, constraints and assumptions Objective 1.4 – Evaluate existing business practices against established use cases
The gathering of requirements (functional and nonfunctional) is an essential part of the whole design and deploy process.
A functional requirement describes what the solution must do or accomplish. Example: Limit access to a specific user group
A nonfunctional requirement describes the characteristics of a solution. Example: Horizon service uptime of 99.99%
To have a good and valid design you also have to define goals, requirements, risks, constraints and assumptions.
Normally, defining goals is one of the easier parts when it comes to a design. When you interview the different key stakeholders and use the right questions, you already have the business objectives or goals. The goals are the business drivers and it’s important for you as architect to understand all the objectives to fulfill the customer’s needs.
What are the company’s business needs? Do they want to increase user mobility? Lower the operational costs with a faster deployment method? Is remote access needed?
If your design process is based on the VMware Delivery Excellence Methodology, then you know that the assessment phase focuses on the scope of the project and the data-gathering for the design. You need to understand the customer’s requirements and for that you need to interview different key stakeholders to create a design which meets all the needs. After you have gathered all the requirements, you must document them and write down the constraints, assumptions and risks.
With all the information about the current state, the business requirements and the application requirements, you are able to create an enterprise infrastructure design based on a three-step model. The conceptual design is the first one to begin with:
I give myself two months to study and prepare for the exam. If I fail to pass in October then at least I know my weak spots. 🙂
Kyran Brophy has also written down how he prepared himself for the VCAP7-DTM exam and was so kind to bundle all the PDF documents mentioned in the exam blueprint.
VMware Certified Professional – Digital Workspace 2018 (VCP-DW 2018)
Since WorkspaceONE is also listed in the exam prep guide, I decided to earn the VCP-DW 2018 certification before I would go ahead and prepare for the VCAP7-DTM Deploy exam next year. Anyway, it seems that the VCAP7-DTM Deploy exam still has not been published yet.
In the next article I will cover first section of the exam blueprint:
Section 1 – Create a Horizon Conceptual Design
Objective 1.1 – Gather and analyze requirements Objective 1.2 – Gather and analyze application requirements Objective 1.3 – Differentiate requirements, risks, constraints and assumptions Objective 1.4 – Evaluate existing business practices against established use cases
In Switzerland sites are often located in the same data center building and two separate rooms represent these sites. To keep management and the architecture simple, some customers or partners would like to take advantage of a vSAN Stretched Cluster.
This question came up several times already at the product management: “Are Instant Clone desktops supported in combination with vSAN Stretched Clusters? And can we use App Volumes?“
The short answer of our product management was that Horizon 7.x (all clones) and a vSAN Stretched Cluster are supported, but that we advise customers to follow the reference architecture design and to test the scalability of the combination of Horizon 7 and a vSAN Stretched Cluster. The caveat is that App Volumes is not supported in this scenario.
But it was not 100% clear if it’s supported to use non-persistent desktops together with a vSAN Stretched Cluster. This gap has been closed with the appendix H:
This new appendix is saying that a stretched active/active architecture is not supported and the use case described in the RA is for full clones only. So, please carefully read our guidelines when working with vSAN Stretched Clusters and Horizon 7.
App Volumes Caveat: There is no support for App Volumes at this time when using a vSAN Stretched Cluster.
My name is Michael Rebmann and I am a “Senior Solution Architect EUC” working for VMware since May 2018. I have just started my journey to become a VCDX-DTM certified architect. As a solution architect I have a customer facing pre-sales role and therefor only need limited technical knowledge, which doesn’t make my life easier to earn the VCDX-DTM certification. 🙂
It’s a long way and I have to start from scratch: Earn the VCP7-DTM certification including the vSphere 6.5 Foundations exam. This means I have to study a lot of PDFs, probably attend a few classroom trainings and also get a lot hands-on experience.
I already passed the online vSphere 6.5 Foundations exam which proves my fundamental skills of vSphere 6.5 environments. My experience from the past with the help of the vSphere 6.5 Install, Configure, Manage course was enough to reach the required score.
On August 16, I will start my first attempt to pass the 2V0-751 VCP7-DTM exam. According to the exam guide the candidate should have between 6-12 months experience working with VMware Horizon including Mirage, App Volumes, User Environment Manager and VMware Identity Manager.
I’m three months with VMware now and let’s figure out on Thursday if the Horizon 7.x Install, Configure, Manage training, VCP-DTM path on Pluralsight and the self-study is enough to pass the exam.
In addition to my VCDX journey I try to share my personal experience from the field. Let the adventure begin!
By the way: So far only 16 people worldwide have earned the VCDX-DTM certification from VMware! Check out the VCDX Directory.