Category: VMware

Achievement Unlocked: VMware VCAP 6.5 DCV 3v0-624 Exam – Summary and Tips

I wanted to start off my Monday morning with a bang, so decided to schedule my VCAP 3v0-624 exam for the first in the morning. Well, I passed!

Before walking into this exam, I wasn’t sure if I prepared enough, but I felt kind of comfortable once the exam started. I’d like to share what I did to prepare for this exam, although this is my first ever VCAP-Design.

Summary of Study Material

  1. VMware Education Courses
    1. I took the vSphere: Design Workshop 6.5 course online a few months ago. This was good at providing a fundamental understanding of VMware’s approach to a virtualized design.
    2. However, I’ve taken other design courses (vCloud Director) so I felt that the approach is very similar. While I reflect positively on this class, I think if you’ve taken other design workshop classes and have a firm understanding of the design methodology, you probably can skip (or take another 6.5 class for my next point).
    3. One valuable thing was the instructor was careful to point on what has changed in vSphere 6.5 (or what’s new). This is very important in my opinion for the Design Exam. So again, positive and a good use of time.
  2. Books I read
    1. VMware vSphere 6.x Datacenter Design Cookbook
      1. I thought Hersey Cartwright’s book was solid on giving me a practical understanding of what to expect for a design and items to be thoughtful on.
      2. While Hersey did write this in the vSphere 6.0x days, it’s still very pertinent and covers many of the important business aspects which seem to be overlooked.
    2. IT Architect: Foundation in the Art of Infrastructure Design
    3. While I enjoyed reading this book, I thought there was more VCDX-preparation level material than specific material for this VCAP-Design test. Perhaps it provided me with a well-rounded approach and drove the thought process. Either way, this is one to keep around for any future planning.
  3. Material I used
    1. Print out BOTH the 6.5 Exam Guide AND 6.0 Exam Guide and review both. For my own study method, I ensure I go through EVERY topic and write them out on my whiteboard. I ensure I cover each one to the best of my abilities.
    2. vBrownBag VCAP6-DCV Video Series
      1. This was AWESOME! I spent quite a bit of time going through each video and taking notes.
      2. I felt this material was very pertinent to the 6.5 Design Exam. Although the Visio drawings are not on the test anymore, the design methodologies remain constant and everyone did a great job of walking through each subsection.
    3. VMware Material
      1. Review the VMware Validated Design Material
      2. I downloaded ALL vSphere 6.5 new documents, along with the following:
        1. vSphere 6.5 DRS Performance Whitepaper
        2. Deploying Extremely Latency Sensitive Applications in vSphere Whitepaper
        3. vSphere 6.5 Virtual Machine Encryption Performance Paper
        4. vSphere 6.5 What’s New? Whitepaper vmw-white-paper-vsphr-whats-new-6-5
        5. vSphere 6 Fault Tolerance: Architecture and Performance Whitepaper
        6. Platform Services Controller 6.0 Topology Decision Tree
        7. vSphere Availability – VMware vSphere 6.5 Document 
        8. vSphere Storage – VMware vSphere 6.5 Document
          1. I was pretty comfortable here, so did not review all of this since it’s the standard documentation.
    4. Other Material
      1.   CADs- Constraints, Assumptions (Risk, Requirements) & Dependencies- see attached.
      2. Conceptual_Logical_Physical_It_is_Simple – see attached
      3. Design Example – pretty sure I found this on the VMware Community Forum. design examples – conceptual,logical,physical
    5. vCommunity Material – honestly, this was a huge component as many others have created some great material out there. This is not in any order, all is good and pertinent.
      1. Graham Barker’s VCAP6-DCV Exam Preparation Guide – very detailed for Sections 1 and 2. I loved how he created sample tests to gauge your knowledge of each section.
      2. Matt Callaway’s VCAP6-DCV Design Study Guide – links to many of the videos but other applicable notes he created.
      3. Hersey’s write-up on exam experience and study notes – again, very good and the callout for the books too.
      4. David Stamen’s summary and important notes – I would stress the importance of David’s tips. They are SPOT ON!
      5. Rene van den Bedem’s Availability Explained post – very good and thorough.
      6. VirtualTiers Sample Quiz by Jason Grierson – really cool site that provides a sample design. Again, many of the questions are the Visio-type stitching but drives the thought-process around the design.
      7. vMusketeers VCAP6-DCV Design Quiz – a lot of work was put into this. Again, driving and testing your knowledge

Exam Tips

  1. I think many of the vCommunity members covered a lot of the specific things, but I will point out things that come top of mind.
  2. Know your Requirements, Assumptions, Constraints, and Risks. Practice, practice practice! I had a hard time understanding functional versus non-functional and then it finally clicked for me.
  3. Understand your AMPRS – Availability, Manageability, Performance, Recoverability, and Security. Again, practice these and understand what are the specific metrics and how non-functional requirements can be categorized in each respective role.
  4. Don’t be afraid of reviewing the 5.x and 6.0 VCAP-Design material. Again, all very pertinent.
  5. Be well prepared for anything that has changed in vSphere 6.5. There are many things that may have changed or enhanced so you’ll need to have knowledge of these aspects.
  6. Last of all, make sure you have working knowledge of design scenarios. I think this has to come with experience and dealing with actual customer situations. This does come with time and exposure.

Post-Exam Thoughts

  1. I thought the exam was very challenging, yet fair. Like I said before, this is my first VCAP-Design, so I cannot comment about the Visio-drawings that were required (albeit I heard these were difficult).
  2. Expect a lot of thought process on each question. TAKE YOUR TIME, you will have plenty of time. I had an hour left even after reviewing every question twice.
  3. Expect the multiple choice, select “x”, and drag and drop.
  4. Go with your instinct and ensure you read the questions clearly.

I hope this helps others – cheers!

-Daniel

Photon OS – no ping and no ICMP replies? Other quick hints on Photon too.

So I’ve been playing with Photon OS recently with a few of our Cloud Provider solutions, very nice lightweight appliance.

However, one thing that surprised me is the minimal/lightweight install does not have ping installed nor can you ping it (ICMP echo replies). In my opinion, this is a basic function for any type of network troubleshooting. I understand it’s minimal…but go cut something else out. 🙂

So how do we set up some basic network functions?

Setting up a Static IP

  1. cd to /etc/systemd/network
  2. vi (or use your preferred text editor) a file called 10-eth0.network
  4. There’s three sections required: Match, Network, and DHCP
    1. Below is the code required:
    1. [Match]
    1. Name=eth0
    1. [Network]
    1. Domains=HOSTNAME domain.local
    1. Gateway=192.168.110.1
    1. Address=192.168.110.61/24
    1. DHCP=no
    1. [DHCP]
    1. UseDNS=false
  16. Save it (wq!), and now it’s time to chmod the file so it can be read by the OS
  17. chmod 644 10-eth0.network
  18. Now we should see the correct permissions: 
  19. Now restart the network daemon service.
  20. systemctl restart systemd-networkd
  21. Complete!

Installing Ping on Photon OS

  1. Pretty easy – as you can see, doesn’t exist. 
  2. Now there’s two different versions of Photon – version 1 and 2. On version 1, it’s pretty easy – type in the following:
    1. yum install iputils
  4. Now for Photon 2.0 (which I’m currently using), repos are disabled by default and so I was getting a message stating “package not found” which was odd. However, digging in further, I found the repos were not enabled.

    1. Enabling Repos so we can pull iputils

      1. cd /etc/yum.repos.d/
      1. I enabled three repos:
        1. photon
        1. photon-extras
        1. photon-updates
      1. We need to edit each file and change the enabled=0 to enabled=1
      1. Once I did this, run “tdnf repolist” and we should now see the following:
      1. Now let’s install it!
      1. tdnf install iputils
      1. Now we should see the following: 
      1. Sucess! Ping is available now, along with netstat too.

Allow ICMP echo responses

  1. This is a change in the firewall table. By default, ICMP echo and replies are dropped.
  2. Here are the two commands required to enable ICMP traffic:
  3. iptables -A OUTPUT -p icmp -j ACCEPT
  4. iptables -A INPUT -p icmp -j ACCEPT
  5. Before I make the change on my system, I’m unable to ping
  6. Make the iptables change….
  7. Voila! We now get a response. 

One last tidbit – SSHD not starting?

  1. During some of my testing, my lab environment went bottoms up – thanks, Timo 😉
  2. After my Photon appliances started back up, I could not SSH to them. So after some troubleshooting and help from the VMware internal team, figured out what happened.
  3. Steps to resolve:
    1. Log into the console and ls -l /var/vmware/skip_sshd and you can also check the status of sshd by typing “systemctl status sshd”
    1. If the file does exist, you need to remove it. No clue why it was added when I had a hard power outage, but it did.
    1. rm /var/vmware/skip_sshd
    1. Now start up ssh..
    1. systemctl start sshd
    1. Voila! we can now see it’s started
    1. Now, SSH works! 

Other great details on Photon commands can be found here: Photon OS Troubleshooting Guide

Thanks!

vSAN Specialist Exam 2VB-601 – Tips

This was on my radar from last year but did not have enough time to get this done. I sat and passed the vSAN Specialist Exam today and wanted to share my feedback and experiences on how I approached it.

Read the Exam Preparation Guide

I know this is stating the obvious, but the blueprint should be your compass on preparing for this test. It reviews the Exam Sections and what to know before taking this test. Moreover, there are 10 practice questions to gauge your level of knowledge. When I started, I tested myself and knew what areas I had to prepare further for.

Download the latest guide here.

Read Storage Hub!!!!

I cannot stress this enough – storagehub.vmware.com is a WEALTH of information.

I went through each section and read each pertinent area of focus. Moreover, the Storage Hub has some nice features. Did you know you can export each respective section to PDF or mark it offline?

Very nice options for travel. I read quite a bit on my iPad and highlighted things I did not know.

What’s amazing is the depth and completeness of our documentation. I learned SO much by reading through many of these detailed documents. This should be everyone’s single source of truth for all things vSAN. Our vSAN Technical Marketing and Engineering teams have done a great job of making the inner-workings of vSAN public.

Do the Hands-on Labs!

There are three great labs available:

  1. vSAN 6.6 – Getting Started
  2. vSAN 6.6 – Challenge Lab
  3. Storage Policy Based Management

They are very comprehensive and cover your typical tasks within vSAN deployments and designs.

Exam Experience

I haven’t taken any of the Specialist exams before, so this was my first experience. I thought the test was fair, and not easy but not very difficult either. If you know vSAN, you should be able to knock this out. Key factors for preparation:

  1. Ensure you know how to size an environment. This is important in real life, but you should be able to calculate raw and usable sizes on the back of a napkin.
  2. Know your FTT policies.
  3. Go build vSAN in your lab and play around with it. I think this is critical to the learning process and also passing this exam.
  4. Last of all, know how storage operates. Having a storage background *does* help here.

It’s 60 questions and you have 105 minutes to complete, which in my opinion is plenty of time. I think I went through all 60 questions in about 35 minutes or so and was able to go through again and review all of the questions.

Good luck and onward to my next challenge!

-Daniel

Meltdown and Spectre Vulnerabilities

25Jan2018 – Updated with latest VMware Public KB for vCloud Director info

I’m sure many of you have heard of the Intel CPU vulnerabilities and how they can impact x86 architectures – I have a feeling this is just the start of something larger too.

I’ve had many Providers reach out to me, very concerned about how this can impact a SP design, especially with virtualization.

To step back, I found this very simple depiction that was shared on Twitter that summarizes the two vulnerabilities – thank you Daniel Miessler (link to his blog article):

So, what does this mean for VMware Cloud Providers? Well, official statements are underway, but here’s what I know so far – again, this is NOT an official statement:

Further information on Spectre and Meltdown on the newly created URL: https://meltdownattack.com/

As I see further information, I will continue to share – this impacts everyone and I have a feeling this is something we all will be dealing with for a long time.

-Daniel