As the VCAP-DCV Design 2020 certification is going to be released (but the 3V0-624 exam is not scheduled to be retired yet) on Jan 1, 2020.
Recently I made another post about my experience with this exam where I failed, check it here.
For your information, at the moment the 3V0-624 is the current exam code for the VCAP-DCV 6.5 Design certification (Also named VCAP-DCV Design 2019), always check the code for the exam no matter which is the certification name.
I decided to share with you some notes for this kind of exams no matter which version.
This information will be more helpful for people that have never taken this exam rather than those who are experienced in these advanced exams.
The Design exams (VCAP-XXX Design) are mainly for IT Architects (sounds cool?) but, why for architects? Well, if you check the blueprint, you will see a couple of sections and not many objectives. The truth is hidden inside each section, which is huge and covers many aspects.
Could you pass this exam without being an IT architect? Of course!
Many did it (not in my case yet) by studying and having a lot of design experience, or also helped doing designs with other peers for example. Also, you can gain all the knowledge of all areas and study your main gaps.
The goal is to design VMware solutions to meet specific goals and requirements, ideally, you should have advanced knowledge of storage, network, compute, end-user computing environments and other components.
You will have to develop a conceptual design given a set of customer requirements, determining which requirements needed to create a logical design and after that creating a physical design with these items.
As you are aiming for a VMware certification, you must think in all solutions, features, and elements from vSphere.
Here is a list of the solutions that appear in the Blueprint and are related to VMware of course:
Inside each solution, you should know at least the most of the features, functionalities that they offer, dependencies between them and test them (if you can).
Apart from knowing about these technologies related to VMware, there are obviously the core areas that compose a general IT infrastructure: Storage, networking and compute.
So, be prepared to dig on each area and know about dependencies between each other and with other solutions.
Advanced knowledge is desirable (and you will be tested) on each area would deserve more than post so, I am not going to explain anything right now about it 🙂
Aiming for the exam
Your main guide must be the blueprint, no matter what other unofficial guides say (although they are very helpful). In the blueprint you will have all the sections and objectives that will be qualified.
This exam requires to read a lot (more if your daily job isn’t designing solutions) and not just books to gather information about how to gather requirements from the customer and match them to terminologies like RAMPS or RRAC (I will explain a bit of those later), also all the technical papers that the blueprint mention (+50).
Conceptual, Logical and Physical Design, you will see this a lot and once you understand it, you will see why.
You must check all the references (documents) that the blueprint mentions because most of them will appear in the exam.
Some key points from all the features, elements or products I think will be:
Dependencies: Know the dependencies between solutions. What do you need to enable vSAN, apart from at least 1 SSD/Flash and 1 SAS/SATA disk? It also requires vCenter and DNS.
Advantages and disadvantages: Does SRM perform replication? Is HA better to ensure availability than FT? Which solution can achieve a 5-minute RPO? vSAN
Maximums and limitations: vSphere 6.5U1 supports a maximum of 4 PSCs per site, behind a LB. Also a maximum of 10 PSCs per vSphere Domain.
Upgrade paths: How would you upgrade a vSphere 6.0 environment to 6.5 with external PSC?
Determine RCAR: Differentiate between requirements, constraints, assumptions, and risks.
RAMPS: Build recoverability, availability, manageability, performance, and security into a vSphere Logical Design.
Gather and analyze business and application requirements from customer interview data, determine customer priorities for defined objectives and categorize those requirements by infrastructure qualities.
In the post, I mentioned to you at the beginning there are some resources which are quite helpful in order to learn and improve your non-tech skills.
There is so much information to digest if you don’t have a certain level of knowledge in vSphere and the “art” of designing solutions, which could lead you to study a lot of products, methodologies, and features in probably, a great amount of time.
But don’t be impatient, it will take you time but, review each section and check the concepts, products or features that you’re not familiar with.
Check videos and other unofficial guides that probably will make other fellows from the community.
This exam is about theory so, you will be tested as an architect who designs solutions based on customer or application requirements and how to match them to a VMware design.
It is difficult to generalize all the things that can appear in past, present, and future VCAP-DCV Design certifications but I tried to give you as much information as I can.
Recently I took the 3V0-624 exam (a.k.a. VMware Certified Advanced Professional 6.5 – Data Center Virtualization Design Exam) and I failed (266/500).
I took it on September, 4th (a month and a half ago) and as I was on holiday and now preparing things for VMworld Europe I won’t be able to study after the event.
I recognize, I study a bit in a rush. In just one month for someone who is daily tasks aren’t about architecture, it can be hard (or not). In my case, this rush was influenced due to leaving on vacation for more than 2 weeks. Then, I decided to give it a try before leaving but, the outcome wasn’t what someone would like!
Let me share my experience in the exam, some thoughts, resources, and notes that maybe can help you.
What I want to say in this section is knowing your limitations and experience against the exam. I am not going to do a comparison against the blueprint right now but, check the blueprint and be honest to yourself.
This exam is called “Design” and that means having a broad knowledge on many areas (like networking, storage, computing, hardware, etc.), a different mindset than an engineer (the famous “holistic” view that architects have).
So, basically, check all the sections in the blueprint and match them against your knowledge. Are there too many gaps? Then, you probably need more experience and a lot of time to study (or both) but definitely, the experience becomes very handy for this exam.
(I recommend you to check the blueprint from the VCAP6-DCV Design which is quite better than the 6.5 version (in fact, it has the resources split into sections instead of giving you a list of 50+ resources like in the 6.5 version).
I am not an architect but I did some projects from the scratch (small ones) and participated in others that were normal (I don’t want to say big because it is subjective) as a technical reference so, I had some of the knowledge regarding how to approach a project
Expect to gather the requirements, find “RRAC” (Requirements, Risks, Assumptions and Constraints) and also I had knowledge in DC architecture, vSphere (obviously) and other products from VMware (this is a VMware exam so don’t expect another thing!).
There are many resources that you can find on the internet:
IT Architect: Foundation in the Art of Infrastructure Design: A Practical Guide for IT Architects
VMware vSphere Design 2nd Edition
Obviously I reviewed all the technical papers from the blueprint and you should too (at least check if you understand the main concept).
As the official webpage states, there are 60 questions and you have 135 minutes (2 hours and 15 minutes) to complete the exam. This is plenty of time for anyone I think.
I read other experiences and almost anyone had a lot of time left in the clock before finishing the exam. When I took it, I reviewed the questions and there were almost 30 minutes.
Questions can be large so, maybe you want to read it a couple of times or even when you’re answering it.
The format of the exam is multiple-choice, matching and drag and drop. That means that all questions won’t have a single choice solution.
Even I had time to finish the exam without looking at the clock too much, I failed with a score of 266 (passing score is 300 like many other VMware exams). That means that I need to review which were my weakest points, resolve my doubts and catch up with all I studied a couple of months ago.
As far as I know, this exam goes until ESXi 6.5 U1 (which is the latest release before the blueprint came out).
Review dependencies between all products and features within vSphere (especially the ones related to the RAMPS concept).
The conceptual, logical and physical design concepts must be mastered.
Review limitations on each feature (HA, DRS, FT, etc.) or product (vSAN, SRM, etc.).
The vBrownbag videos and books like the “VCAP5-DCD guide” can be very helpful even though are “older”. About books. the “vSphere Design 2nd edition” along with the “IT Architect series: Foundation in the art of infrastructure design” will give you a general vision of all concepts that an architect must know.
Check the blueprint from the VCAP6-DCV Design as the objectives are the same as the 6.5 version but better explained and with references on each section.
So, that’s all I wanted to say and I hope that even I didn’t pass in this first attempt, it can help other people willing to take it in the future.
VMworld 2019 Europe is almost here! And I made a local guide with tips about transport, restaurants, places to go, etc. to ensure you can enjoy more your experience in VMworld.
This event will take place from the 4th (Monday) to 7th (Thursday) of November at Fira Gran Via in Barcelona, Spain.
VMworld is always an amazing opportunity to learn from all the events that will happen there like the Hands-on Lab, Breakout sessions, General sessions, etc.
Also, it is a great way to connect with a lot of people from the community, vendors or other persons that you are interested in.
People are really friendly so, don’t be shy (you can try first on Twitter!) and try to speak to members from the vCommunity. Besides, be sure to meet the vBrownbag team in the VMTN Tech talks area 🙂
If you are interested in attending this amazing international event and enjoy many other advantages, you can register here.
In Spain, tipping is entirely optional and it’s not very common so, it’s up to you if you want to leave a tip in case the service was exceptional or you think it deserves it.
In restaurants, shops, etc. the VAT tax is included. Therefore, you don’t have to worry to calculate an extra amount of money.
Also, once you pay with credit card (VISA branded cards are the most used here) they will make you enter the PIN code of your credit card (a bit different than the US).
I know it’s late but, hotels near Fira are nice and a bit expensive. The best zone I think it is near Sants where there are cheaper hotels, nice transport connections, and great ambient.
The official language in Barcelona is Spanish but most of the population speak in Catalan. Saying that, don’t worry if you don’t understand some signboards from the street or public places.
There are 3 different train services: Renfe (Local Train), TMB (metro/subway/underground) and FGC (Regional Train).
Renfe and TMB are the most used because they have more combinations than the FGC and also better schedules. So, basically, you will see in this guide mentioning train for Renfe and metro/subway/underground for TMB.
Coming from the airport
Once you land at El Prat airport, there are a few ways to go to the city of Barcelona:
You can take a taxi (expensive but more convenient for people with less time or when the hotel is located in an isolated area). It will costs between 20-30 € from the Airport to Sants (always depending on the traffic). Put the hand luggage on the taxi trunk costs an additional euro.
You can use the app myTaxi to order one. Uber and Cabifiy are not available in Barcelona.
Use the L9 Sud line, this is the Metro (subway/underground) service and can be combined with other lines (like L5 at Collblanc stop for example) within the same ticket.
This metro service is more frequent than the train service and it costs 4.60 €. This can be the best option for most people because you can use the same single ticket to go to other places by combining lines.
By bus (Aerobus):
The least recommended option as it will be crowded but it depends on your preferences and where do you want to go.
The Aerobus will take you to “Plaça Catalunya” (Catalunya Plaza) but it costs a bit more than other services (5,90 € at the moment), you can review more information in this link.
If you plan to visit Barcelona, consider buying a T-10 ticket (which includes 10 single tickets or 10 journeys) as it will save you half the price of many single tickets. This T-10 card can be used for many people as you want so, consider it if you are a group.
T-10 cards are sold by zones (because they have other public services integrated), as you are going to stay in Barcelona, you only need 1 zone. Price for a T-10 1 Zone card is 10.20€, versus buying 10 single tickets (1 zone) will cost 2.20 € x 10 = 22€.
T-10 tickets can be used on any public transport (bus, Metro, Renfe and FGC services) with some exceptions covered here:
You cannot use the T-10 ticket from the airport on the Metro Line L9 Sud. This means the T10 ticket is not valid at the stops Aeroport T1 or Aeroport T2 on the airport metro link.
The Metro (subway/underground) is your best choice whatever you stay in Barcelona if you want a cheaper, frequent and reliable service.
With the metro (remember the name) you can travel through lines at the same cost. The main stops to consider will be Fira in L9 Sud, Plaça Espanya in L1/L3 and Sants-Estacio in L5/L3.
The fastest way to VMworld?
The closest stop to the VMworld event isFira in L9 Sud or theEuropa-Firastop which is another stop from the L9-Sud line that also combines with another train service(FGC trains) which is a different transport service than the metro and it has different stops.
If you stay near Sants, the Sants-Estacio stop in L5 will be your choice. Then, in Sants-Estacio station take the L5 to Collblanc stop and after that, change the line toL9 Suduntil you arrive at Fira stop.
You can see in the following map the VMworld precinct highlighted in yellow and the closest stops (marked in blue): Europa-Fira stop which combines FGC and Metro services and, Fira stop at L9 Sud.
Last year VMworld provided a free metro card; As I don’t know if it will be the same but if you are aiming to visit Barcelona and visit other places, consider to buy a T-10 travel card (10 single rides) which is multi personal and quite cheaper than buying 10 single tickets.
Events around VMworld
Fred Hofer has a magnificent post where it summarizes all the events and parties that will happen on these dates, check it here
I organized the vFit runs, review my post for more detailed information
In my case besides the vFit event (Monday and Wednesday morning), I will attend the vSoccer event on Monday night and vBreakfaston Tuesday.
Outside VMworld (Sightseeing)
Here is a summary of the places that you could visit if you come to Barcelona:
La Sagrada Familia
Probably the most iconic building in Barcelona. It is an unfinished church designed by Gaudí, an architect who made many iconic buildings here in Barcelona.
The most famous pedestrian street of Barcelona, you will see many kiosks and artists there while walking in the middle of the city. Note: Keep an eye on your belongings if you are watching an exhibition as pickpockets could be near you.
La Font Màgica de Montjuïc (Magic fountain of Montjuïc)
This fountain is amazing at night. You should check the exhibitions scheduled with lights and streams creating shapes. It is located near the Veeam party that will be on Tuesday so, maybe you can go earlier and check it out!
A gorgeous park with some designs from Gaudí and other architects that are interesting. You must buy a ticket in order to gain entrance to the Monumental Area (where you can see some monuments from Gaudí).
A famous building designed by Gaudí also named “House of bones”. Look at the facade which is something that you probably never seen before with the sculpted stonework, the windows or the painting. It is also a museum where you can visit (you need to buy a ticket) the inside of this building.
The Olympic port of Barcelona (since recent events in the past months, I will avoid going at night)
It is one of the most exciting leisure and touristic spots throughout Barcelona, with a wide offering of shops, clubs, and restaurants. It’s the gateway to the Barcelona beaches and also there is the Barcelona zoo near to it.
In general, avoid going alone in the night, especially in “Las Ramblas”, “El Raval” or near “Olympic Port of Barcelona”.
Also, avoid the neighborhood known as “La Mina” which is farther from Barcelona but it still accessible by Metro.
The food in Barcelona is nice and some of you probably know it.
Let me suggest a couple of restaurants near Fira Gran Via (VMworld):
Gran Varela: A restaurant with great food (especially octopus). Also, the wines are great!
In Gran Via 2 (a shopping center pretty close to Fira Gran via) I can suggest you:
A great Japanese (Udon)
A good Italian (La Tagliatella)
Beers and tapas (Cañas y tapa)
Restaurant La Vid: A nice restaurant where you can try local food like the bread with spread tomato, the Spanish omelet, or the ham! This is also the restaurant that will be hosting the vBreakfast event on Tuesday morning.
The best places aren’t near Fira Gran Via but if you want to try better food, here are a couple of restaurants that are really nice:
Bacoa Burger: Amazing and customized burgers, also hand-made fries and sauces.
König: Amazing restaurant where you can try almost everything: tapas, amazing beer, flatbread, and many other options!
La Bella Napoli: Not many choices on the menu in this Italian restaurant but the food quality is amazing.
So, that web page mentions the “VM network” port group that is a default port group that is created once you deploy an ESXi host. In my case, it was auto-deployed with different port groups and that one didn’t exist.
Hence, I decided to create a port group called “VM Network” in the host that I am trying to deploy the vCSA and…it worked!
Now, as you can see, I can see that port group and I was able to continue the installation with success!
It seems that with you must have this port group if you are deploying a vCSA at least from your PC, so, bear in mind if you are trying to deploy a new vCSA and you don’t have the default port groups when deploying a vCenter Server.
As said in previous articles, this series is only focused on VMware vSphere hence, VMware Horizon View is not contemplated (Linked clones are commonly used in that product).
What is a linked clone?
What can you see here?
In the previous image, you can see 3 different characters but they share something in common…the actor!
Linked clones are the same! A linked clone is a type of clone (a copy of a virtual machine) where the parent VM shares virtual disks with their clones.
The resulting linked clone will be created from the parent’s VM snapshot and because of being a snapshot, it will have the same state that was the snapshot was taken.
When the linked clone is created, it shares his own virtual disk (.vmdk file) with the snapshot from the parent VM, this leads to some unique features:
The clone will be dependent from the parent VM because they are sharing their virtual disks. If you delete the parent’s VM snapshot, it will corrupt the clone’s virtual disk.
Even both VMs are sharing their storage, any changes performed in the clone won’t affect the parent VM and vice-versa.
The linked clone will have the exact same data as the source VM because it was created from a snapshot.
The save spacings are obvious because the clone will only write the new modifications in its own virtual disk. So, the clone’s virtual disk size will be only the amount of data that changed after it was created!
Use or prepare a VM (Parent VM) that will be used as a master/parent to deploy the linked clones
Power-off the Parent VM (Recommended but not mandatory)
Perform a snapshot of the VM.
Time to create Linked clones referencing the snapshot we created previously.
Power-on the clones and customize them (apply customization specifications for example).
(Extra) Before powering-on the linked clone, perform another snapshot of the clone to use it as a rollback (if the end-user needs it).
(Extra) Power-on the clone and is ready to be delivered.
(Extra plus) If you decide to keep the linked clone for any reason, you can perform a full clone of it and it will become an independent VM!
In the next section, I will show you how to create a linked clone with PowerCLI from a Windows VM and in my case, I will use Custom Specifications within the script to launch the clone.
Here we have the VM that we’re going to use as our Parent VM:
– Name: SQLMasterVM – IP: 192.168.1.174 – Disk allocation: Around 35 GB summing both disks. – Domain: vmug.bcn
Inside the Guest OS:
Space allocated in DS:
What are we going to do?
Shutdown the master image VM that hosts some DBs.
Create a snapshot when the VM is powered-off to ensure that is consistent (this is a VM with a SQL installed so, even more recommended)
Perform the linked clone via PowerCLI.
Start the VM (We aren’t going to do the extra step of creating a snapshot of the clone) and use custom specifications to fully customize the clone.
All of this will be performed by this simple script:
##Creating SQL Linked Clone from a Parent VM "SQLMasterVM"
$OSSpec = Get-OSCustomizationSpec -Name 'Win-SQL'
$BaseVM = "SQLMasterVM"
$LinkedVM = "SQL-LC1"
# Delete snapshots on the Parent VM
Get-Snapshot -VM $BaseVM | Remove-Snapshot -Confirm:$falseStart-Sleep -Seconds 2
New-Snapshot -VM $BaseVM -Name "Linked-Snapshot" -Description "Snapshot for linked clones for $LinkedVM"
#Gather information of the created snapshot
$snapshotParent = Get-Snapshot -VM $BaseVM | Select Name
$snapshotParent = $snapshotParent.Name
Start-Sleep -Seconds 5
#Create Linked Clone referencing snapshot and start the VM.
New-VM -Name $LinkedVM -VM $BaseVM -Datastore "VMS" -ResourcePool (Get-Cluster -Name Gaiden-Cluster | Get-ResourcePool) -OSCustomizationSpec $OSSpec -LinkedClone -ReferenceSnapshot $snapshotParent -DiskStorageFormat Thin
Start-VM -VM $LinkedVM
In this script, I am also using the OSCustomizationSpec parameter, while using the sentence to create the linked clone, to change the IP, name and join again to the domain the resultant clone. Also, I am changing the SQL instance name in my case because it’s a server with MSSQL server installed.
Once the script finished, a new linked clone is created and powered on with the name “SQL-LC1”.
We can see the amount of time that takes to create a Linked clone (5 seconds):
And now look at the storage allocated by the Linked clone (powered off), 750 MB approximately:
After the Linked clone is created and powered on, you can do whatever you want.
I had to wait some minutes (around 10 min. in my case) until the OS customization specification finish all the actions specified (power on the VM, join to the domain, reboot the VM, execute a script to update SQL instance, etc.)
Here is the “real” space allocated after the Linked clone has booted up and I logged in with a user, around 4 GB:
A look inside the Guest OS of the linked clone (new hostname, IP and has the same storage as the Parent VM:
It’s commonly used in VDI and DEV environments but here are some examples:
DB server testing
File server testing
Benefits and limits
Let’s summarize which are the benefits and limits that we can find in linked clones:
Super fast cloning compared to a Full/Normal clone, it takes seconds instead of minutes to clone large VMs.
Space savings due to changes are stored in a separated disk (clone’s flat disk).
Useful for development environments or if you want to keep the clone just, perform a full clone of it!
Deploy as many linked clones as you want, they will reference the snapshot in the Parent VM hence, there is no disk chain on that (except for the snapshot you created of course) and the benefits of replicating .
Ongoing changes made in the virtual disk of the source VM don’t affect the linked clones and changes to the disk of the linked don’t affect the parent.
It can be performed with the parent VM powered on but, it will have some performance degradation and probably inconsistent data (if for example, the parent VM hosts a DB).
Recommended but not mandatory that the parent VM has to be powered off.
There is a storage/disk dependency as the linked clone is created from the parent’s VM snapshot then, if you delete that snapshot, inconsistencies will occur in the clone (and at the end you will delete it).
Performance on the destination clone will be impacted (as virtual machines are sharing storage)
Linked clones have multiple benefits compared to full clones and it has many use cases as we saw before.
You can easily replicate the status of a VM (snapshot) and deploy linked clones to your end-users with all the benefits as for example space savings or the deployment speed.
To end this series, we will look at instant clones, another type of clone that is even faster than linked clones but, with some particularities.
I am going to talk about my experience at a local VMUG, in my case the VMUG from Barcelona (BCN). It was my first time at a local VMUG event and this is why I decided to share my thoughts about it.
VMUG – What is?
As you probably know VMUG stands for VMware User Group. Basically, you will find an international community of people where they share their experiences and discuss things related to VMware and other technologies.
At your local VMUG, you will find VMUG members that you can meet online or in person, sponsors. There you can find many passionate people about VMware and connect with them, so I highly recommend to attend to the VMUG events as it is a great experience to learn concepts or technologies and connect with a lot of people.
There are many communities around the world if you want to find your local VMUG go and register at https://www.vmug.com/
VMUG – Why attend?
Because you won’t regret it!
I didn’t imagine that the environment and people were so good, everyone is passioned about technology, mainly VMware things, and you can hear their stories and share experiences that both probably lived in your life.
Hence, it doesn’t matter if you’re presenting or attending your local VMUG, the thing is to go there, meet people and learn about the sessions! You will find that a lot of people share some passion for VMware and technology so, don’t be shy to say hello and try to meet them.
Presenting at a local VMUG
I’ve been involved in this local VMUG for a year approximately but, I never had the chance to attend any event. Since VMworld I didn’t hear anything about a new event so, I spoke with the VMUG forum about when would be a new event and finally, it ended with myself presenting my session.
In my case, I presented a session (in Spanish) about Clones in vSphere (I’ll do a post about presenting in the near future) on March, 15th.
You didn’t expect something like my case, I was lucky to present at my first time in this event but, usually, it’s better to go there and meet the people before presenting and not in the other way.
I am glad that I finally was able to attend and meet a lot of VMUG members, you can learn a lot from people through their sessions and also make connections that will be valuable in the future.
I would highly recommend attending and experience the passion of VMUG members and the knowledge that you can gather from them.
Also, I would like to acknowledge the VMUG leaders from the BCN VMUG for letting me present and the sponsors that make it possible.
Continuing with the cloning virtual machines in vSphere series, today I am going to write about the full clone, how it works and some useful information about it.
So, let’s talk about clones… but just full clones.
How does it work?
As you probably know a full clone is an exact copy of a source VM, meaning that, everything from the parent VM is copied (VM settings, disks, files, etc.).
This action can be performed if the parent VM is powered off or powered on and, if it has snapshots it will consolidate them once the clone is done.
When you clone a VM be aware that, all data will be identical so, if you power on the clone without performing any customization, probably you will have conflicts with IPs, MAC addresses, SIDs (Windows), etc.
The great thing about a full clone is that, after the cloning operations are performed the clone will be an independent copy of a virtual machine that doesn’t share anything with the parent virtual machine (we are talking about from a compute and storage perspective within vSphere).
Ways to do it
First of all, you will need VMware vCenter to do it.
There are other ways (not official) like copying all data related to the virtual machine (.vmdk and .vmx files) and then register the “new” VM with another name.
Let’s continue with the usual ways:
vSphere Web Client
You can do it through vSphere Web Client, as simple as, right-click a VM -> “Clone to Virtual Machine…” :
Once it finishes, it takes some time (depends on the storage that the source VM has allocated) but in the end, you will have your new clone.
Likely you are more familiar about deploying templates…
Deploying a template is the same as cloning but. aside from copying the same data from the parent virtual machine, vSphere lets you customize the deployed VM for creating many clones and with different configurations as you wish.
Of course, you can do it with PowerCLI. These are the minimal parameters needed to perform it (Disk Storage Format parameter is optional but recommended because, by default, it will convert all disks to Thick Provision Eager Zeroed):
In the previous screenshot, you can see the minimum parameters required to perform a full clone, if you want to see more options you can check it here.
As you can see in the code, it’s similar to deploying a template, isn’t it?
The main use case is deploying from a template, maybe we are not aware but, deploying from a template is just cloning our source VM (Master template) and then customizing it.
I saw many customers use it as a “rollback” when they have to perform a destructive task within the Guest OS. In this way, just shutting down the parent VM and powering on the clone.
If you think a snapshot can do the same as a clone well, not always… some applications don’t handle well doing a quiesced snapshot.
This is why, as a solution, you can create a full clone when the virtual machine is powered off and then, have a copy that will be consistent and without corruption.
Another use case could be to perform a full clone to use it in other environments. Although there are better ways to do this (with other products), when the Guest OS has many customizations, this can be an alternative solution of re-creating the entire virtual machine.
Benefits and limitations
The benefits of a full clone were mentioned before:
If the cloning operation is executed when the source VM is powered off, it can be used as a rollback in many cases (there are better options like a VM backup but, it can help a lot).
Creation of an independent VM that shares nothing with the source VM.
Used in templates, so, they are very useful!
These are some limitations instead of disadvantages that we can find:
It takes some time to create a full clone (it depends on the allocated storage) as it has to copy all storage from the source VM.
It can only be performed with VMware vCenter (there are other ways as I explained before but they are not official).
If done when the VM is powered on, it has an impact on the source VM that can be noticed by the business so, isn’t the best option to do it while the virtual machine is in running.
To sum up, a full clone is a great way to have an identical copy of another VM to use it as a permanent virtual machine once you configure it accordingly.
As said before, is the same as deploying a template because you are just cloning a VM (deploying a template) and then customizing it.
It usually takes some minutes to finish the clone (depending on the storage allocated in the parent VM), this is why there are other ways to deploy clones in a faster way (on the next posts!).
Most of you already know how to clone virtual machines within vSphere, and I mean cloning from the vSphere Web client within vCenter but, beyond that, there are other types of clones you can use in vCenter like, Linked Clones or Instant Clones (aka Project Fargo/VMfork)
Due to the large content that can be discussed about each clone’s type, I decided to make a short series of posts talking about cloning VMs!
Types of clone
Here I will summarize each type of clone that exists in vSphere, some of them are used in different products or interfaces but in the end, all of them are accessible through PowerCLI.
This is the “classic” clone you can perform in vSphere Web Client no matter which is the VM’s status (powered on or off), that you can perform a copy of the VM.
If you want to perform a consistent clone, it’s recommended that you power off the VM and then perform the clone.
This is an independent copy and has no dependency from the parent virtual machine after the clone is complete (meaning that you can remove the parent VM if you need it).
The main advantage is that you can have a reliable copy of the Parent VM (remember this is not a backup) if you want to replace it. As this is a full copy of the VM (it will copy the entire disk), this might take several minutes depending on the size of the VM.
After you perform it, remember that everything will be the same then, all configuration (SID, network configuration, hostname, etc.) within the VM will be identical hance, it can lead to problems if both VMs co-exist at the same time without the proper configuration.
Is a clone made from a snapshot of the Parent VM. This means that both VMs (the Linked clone and the parent VM) have in common virtual disks.
So, the linked clone is dependent on the parent VM, meaning that the linked clone needs access to the parent VM. The clone must be done while the Parent VM is powered off (as a best practice).
Once a linked clone is performed, changes on the parent VM doesn’t affect the linked clone and in the other way, changes in the linked clone don’t affect the original VM. Mainly the benefits of using linked clones are:
Saving disk space because only the differences between the origin snapshot and the linked clone are allocated and the fast.
Quickly deploy tens or hundreds of VMs in a fast way as it doesn’t need to copy the entire disk.
This is a technology commonly used in VMware Horizon View to provide desktop deployment (rapidly deploy a lot of VMs). The thing is that we can also use it with PowerCLI without having Horizon View and use it for more use cases.
Similar to the linked clone, Instant Clone is like an improved version of linked clone technology. This is something “new” in vSphere 6.7 as is available through the API.
Like the linked clone technology, there is a parent VM which will share the disk with the clone (Instant clone) but, in this case, it will share the memory too (even if TPS is disabled).
There are two types of Instant Clones that I will explain in more detail in the next posts but, as a summary, you can do an instant clone from a source VM from a point in time and deliver many VMs (instant clones) as you want.
The Parent VM must be powered-on instead of powered off like other types of clones, in this way, it can provide even a faster way to deploy VMs because it will not require to power-cycle the Instant Clones.
As benefits, we will have the same as in Linked Clones technology plus memory efficiency (because it shares memory between VMs) and the ability to resume the VM in a point of time without power cycling the clone.
In the other hand, depending on which type of instant clone you can run with a lot of delta disks.
I tried to summarize each clone’s type that we can perform within vSphere and if you want to read more, stay tuned to go in more detail in the coming series of posts related to cloning VMs within vSphere.
Also, I’ll be at VMFest on Wednesday and maybe other parties but I can’t assure anything.
I am going every day except for Thursday that I’ll leave before 1 PM.
My schedule is built with sessions, workshops, parties (just a couple) and obviously a couple of hours of free time, to network and do whatever I want (also relax, as it seems that can be exhausting). Remember that all sessions will be recorded so if you can’t attend it, you can watch it later.
About the parties, I won’t be able to stay too late because I need to come back home and we have more days to enjoy VMworld.
If you want to talk or something (like play some video games), you can find me on Twitter (I am really active). I’ll be open to everyone in the community!
Even I know I am not a famous guy, (and don’t pretend to be it), talking with new people can be satisfying and it’s always great to meet someone new. If you are shy you could try to engage someone on Twitter and let him/her know that you are there!
As it is my 1st time I can’t give any advice on this, you should check other blogs for that.
P.S. I wanted to meet especially (among other people) Ariel (@arielsanchezmora) but it couldn’t be as he can’t assist.
Hi! I am going to talk about my VCAP6-DCV Deploy exam experience.
I thought about making a huge post about the VCAP6-DCV experience (resources, notes, etc.) but, I don’t want to overwhelm you know. Hence, I am going to make another post for that, hence this post will be shorter and more readable.
1st attempt (Java error at the beginning)
At September, 21st I sat down to take my first attempt in a VCAP exam. I was confident because I was studying the previous 10 weeks approximately and I covered all the objectives.
Well, my exam was scheduled at 10:00 AM, I sat down and my exam starts. The interface is exactly the same as the HOLs, so, if you familiarized with it, you will gain a lot of time!
The lab was deploying and the manual on the right side showed some information but as soon as the lab finishes to deploy…bum!
A Java error appeared: Java error: Unhandled Exception, then I pressed OK and my exam finishes itself!
I contacted the TA and she told me that my exam was finished, and I was like “What? In 2 minutes?”. After spending some hours with Pearson VUE, the TA (Test Administrator) opened a case with Pearson VUE and I left the Test Center.
I left with a feeling that this test center has serious issues, the TA didn’t know how to speak in English (I was taking it in Barcelona, Spain) and finally, I ended talking my self with Pearson VUE and explaining the problem. They couldn’t do anything as my exam was finished (it wasn’t my fault obviously)
A week later I received a voucher code for my crashed exam.
2nd attempt (Manual stuck in loading)
This second attempt was scheduled at October, 5th. I rescheduled in another Test Center as I didn’t trust the TA for that Test Center.
The problem you face with the VCAP exams is that they are delivered in fewer Test Centers, therefore, there are less available spots to take it. I found another Test Center here in Barcelona, so I scheduled there even I didn’t know that one.
Well, my exam started at 10:00 am, the server’s console loaded correctly after the lab was deployed (nice!) but, the manual didn’t appear, there was only a grey window without content.
After waiting for 5 minutes, I spoke with the TA, and he told me to wait another 5 minutes. So, as expected, the manual was stuck loading and even trying to stop and start the exam didn’t fix the problem.
Hence, the TA contacts Pearson VUE and Pearson VUE fixed the problem this time! But what happened with all the time I lost in my exam? Well, the TA told me Pearson VUE would contact with VMware and the time will be added meanwhile I am taking it.
At that time, the exam started again but I had a weird feeling about.
In the exam, I finished writing down each question number and a brief description on the erasable board, in this manner, I could check quickly which questions I can take first and cross out which I have done.
It was curious that at times, backspace and shift keys worked in Putty. Also, occasionally, during 5-10 minutes I experienced quite delay with the Web Client. I continued with the exam, contacted with the TA about the time but no response from Pearson VUE and time were running out…
The time isn’t going to be added, hence, I had to left like 4 or 5 empty questions because I didn’t have more time (I lost 30 minutes) and the exam finalizes automatically. I felt bad because of the 30 mins. would be nice to try other questions.
After that, I spoke with the TA and he opened a case with Pearson VUE about the time lost. One hour later, I received my score report, 278/500 (almost got it!).
After a few days, Pearson VUE reviewed my case and, as I was close to passing the exam (remember that you need 300/500), I suppose they decided to give me another voucher code, so I felt good about the free re-schedule but bad for the score and the time lost.
3rd attempt (Redeployed lab and final attempt)
Well, this is really a lie, because I “took” 2 exams in a row. Let me explain…
On October, 16th, my exam was scheduled at 10:00 AM, I studied a bit the previous night just to remember some things. My last attempt was 11 days ago and I was focused on other things so, it’s always good to brush up some concepts.
Well, the exam started and the lab was deploying itself… then, it appeared a notification like “Query not found”. This time the manual loaded correctly, but the pop-up appeared all the time, appearing and disappearing, and the console didn’t load as the error appears instead.
Therefore, the TA (Test Administrator) contacted Pearson VUE and for my surprise, Pearson VUE this time could contact VMware quite fast. The TA told me that VMware was going to redeploy another lab (Now my time wasn’t wasted at all!) and I could try in 30 minutes.
Finally, I tried again and it worked correctly, the manual and console loaded correctly so, I took the exam. The connection seemed a bit better so I can’t complain about. Also, the backspace and shift keys worked as in my previous exam, therefore, I took advantage of it.
Now, I tried to answer all questions (I left 1 answer empty because I didn’t want to lose more time) and I finished my exam (well the lab finished and it closes automatically) with a good feeling.
In 1 hour approximately I received the email and…a PASS! Couldn’t be happier! Finally, a full exam without issues made me pass the exam!
I can do a recap of what I learned about my experience with that exam and all the issues I experienced:
If you have any problem, contact your TA, don’t waste time to wait for the manual or console to load.
Test if backspace and shift keys work! I was concerned that these keys were blocked but I was able to use it and avoid the On-Screen keyboard, maybe it can work for you.
Manage your time, manage your time. Everything you will read about this exam (or new ones) is about managing your time and I couldn’t agree more.
Use the erasable board! I used to write down each question number and a brief description, it helped me to know if I was running out of time and focus in the “easy” questions.
Be aware of the dates, it was like a month ago since I scheduled the first attempt, so, if you are going to take it because your certification is expiring, be sure to schedule it in advance.
I am not going sugar coat the fact that I was happy with the exam’s delivery because I suffered many issues…but, finally, with some patience it was paid-off.
I hope this can be helpful for someone and I will write another post about the resources and how I prepared my self about this exam.