Thursday, May 24, 2012

VCDX Defense Experience

Have just finished my Panel defense for VCDX4 in Toronto, Canada.  Just to share the experience on what I have gone through whoever is interested can prepare for next version of VCDX.  Due to the NDA nothing related to the session can be discussed or disclosed.

As usual to be applicable for VCDX certification you need to meet some prerequisites.  This is clearly documented in VMware site here.  You would need to be the version VCP for the version of VCDX you are aftering.  Both VCAP certifications for Design and Administrator which I have also shared the experience in my previous posts.
I never expected myself to have even gone through VCAP certification followed by VCDX.  On a personal note, I wanted to give myself some challenges while on my career in the virtualization space.  The certification not only just show your understanding in VMware solutions but it also enhance what the components to look out for in terms of virtualization solutions be it Xen, RHEL KVM, etc.  I would say VMware exam path is the only so far I see which truly focus on virtualization aspect.

I once talked to a VCDX regarding the proposal.  Does it has to be a big complex proposal?  Since the country I came from often do not have big complex projects.  It doesn't matter the proposal how big or small, how complex or simple.  The important thing is your thought process.  What have you gone through to do that proposal every aspect of your decision and why.  You must illustrate your understanding inside out and be able to know what you are doing.  So the design has to be from you yourself and not taken from someone else or download from somewhere.  It can result in complete disaster for you.

After these are done, will you then go through the application.  Do note there are several payments need to be done.  The first is for the assessing your application which is your proposal.  The 2nd is for the panel defense if you are successful on the application and be invited.  There is no refund if your application get rejected.  That happened to me on my first submission.  So do well on your proposal don't follow what I did without putting in time for it.  A penalty I ought to pay and I did.

Where I came from is Singapore, and there are several panel each year around the world and happened that one was in Singapore.  As I wasn't prepared and ready for my prerequisites,  I have to miss that one.  Subsequently, I applied for the supposed last in Frankfurt, Germany but my application was rejected due to my haste preparation on my design.  I was given comments on my proposal.

Luckily VMware added one last panel again Toronto, Canada.  This time I refine my proposal once again and got my application successful.  Lesson learned here you need to really prepare your proposal.  There is no shortcut.  No matter how you felt your proposal was done perfectly, there is always room for refinement.  So review, review, review.

Having the application gone through successfully, it is time to plan for the defense.  You will be in touch by the officials on the details and stuff.  There are also VMware communities to refer to for all the FAQ and mistakes often made.  I won't list them here since you would only read them when you are already at the final stage and by then perhaps there will be new notices and as well the information which you will received them anyway.

While I was there waiting for my panel defense, I met up with one participant from Frankfurt.  We chatted a bit.  He heard rumours that VMware employee's application gets comments and chance to be amended before the application assessment datelline in order to process their design successfully.  I for one did not receive such treatment.  I strongly believe the process for VCDX is very stringent and no such favoritism were practice.  I have heard many participants to go through the panel several time to even get their VCDX.

I wasn't give any remarks at all from the day I submitted to the date of the dateline.  It was genuine the way I wrote it.

75 mins for your design proposal, 45 mins on Design and 15mins on troubleshooting section.  Its a total of 2 hours 15 mins seems very long.  When you are in the defense, time just flies.  Breaks were given after the defense section.  As a personal level, I felt intense going through the whole process but relieve after it was over.

The greatest advice to those intending to do this, sleep early the night before.  Enough rest.  Avoid going through more research and information on the day itself.  Relax and just go.

It was a good experience for myself.  The results?  10 days later and whether or not I make it, its not really important.  It would be a bonus if I do.  What is the rewarding factor?  The experience going through this.  I have learn many things from this and will be able to do a much better work next time in the future with what I have experience and picked up through this process.

Good luck to those who plan to do it.  Do give up and think you can't do it before you even do it.  Just go for it.  The experience?  Its priceless...

The result is out and sadly I didn't actually make it.  And yes there isn't any bias even though as an employee of the company.  Guess will have to prepare for VCDX5 which means going through VCP5, VCAP5 for both DCA and DCD and lastly redoing my proposal to fit into vSphere 5.

Update 2:
Apparently VMWorld 2012 in Aug at San Francisco will allow the two attempts for VCDX4 while having the first VCDX5 defense.  For those who are still keen to do their final round of VCDX4.  Here is your last chance where defense for VCDX 5 will official be in VMWorld 2012 in Oct at Barcelona.

Tuesday, May 22, 2012

Update vCenter Configuration Manager (VCM) 5.5 License

The release of vCenter Configuration Manager 5.5 on Mar 15, 2012 brought to some attention that there is license update to be done.  The change from license file to serial key make some steps required in updating for those upgrading from previous version to 5.5

My colleague, Clement Wong informed that there is a need and I did also encounter this post in communities.

So to simple update the license file, you just need to browse to the folder in command prompt:
CL\Program FIles (x86)\VMware\VCM\Tools

To see what commands and options are available:
>jlicense.cmd /?

To update your license:
> jlicense.cmd -k xxxxx-xxxxx-xxxxx-xxxxx-xxxxx

Where xxxx is your serial key.

Saturday, May 5, 2012

iSCSI Datastore Extend

Have a question posted by one of my customer on iSCSI datastore extend.

In Linux, if you have two LUN created every time this machine is rebooted, sometimes the LUNs get mixed up e.g. sda for LUN1 and sdb for LUN2 which could be vice versus unless a udev is used to statically map the drive to ensure the path remains the same.

So now if we compare that in ESX, if we reboot an ESX server which has two LUN of iSCSI datastore which one extend to the other, would this cause any confusion placing the 2nd extend to be the 1st extend of datastore?  If not, how does ESX know the iSCSI datastore extended order?

I wasn't able to answer this and got reply from Cormac Hogan in VMware.

No – no confusion would occur.

From a LUN perspective, vSphere uses NAA id (SCSI identifiers) rather than relying on any controller/target/LUN numbering convention. This way, if the LUNs were presented differently, or were discovered in a different order, we know about them from this NAA id.

From a VMFS perspective, both extends would have metadata in their header, but the metadata would identify one datastore as the meta-head and the other extent as just a member.

We have many customer using iSCSI extents, and they work perfectly fine.

There you have it.  Very interesting question and concept on how it work out in vSphere.

Wednesday, May 2, 2012

Hair for Hope

This has nothing to do for technology but for charity.

This year I decided to do something to contribute back to the society.

I have sign up Hair for Hope and will be doing my part to shave my hair.  I would like to seek anyone to do their part but do any amount of donation.

Your support is greatly appreciated.

vSphere Assessment Tool (vSAT)

If you are not aware, there is a new tool announced during VMworld US 2019. That is the vSphere Assessment Tool (vSAT). To access the sit...