The most important part of my installations!!!

Ok I have done some nice VMware projects recently with both blade systems and rack servers, some have been SRM installs across sites and some have been Metro Clusters (NetApp) and some have been bog standard installs with a handfull of hosts at each site.

I have done the , conceptual, low level and then high level design elements before creating an installation guide for the consultants installing the systems (when it has not been myself) and also created a validation plan for the install after to make sure it has filled the fundamental requirements identified in the design phase.

However one of the most important elements of the design recently has been the assistance of migrating workloads.  All of my recent customer have been migrating from an ageing VMware platform to the new system I have been installing.

During the design phase and the gathering of the fundamental requirements one of the key requirements is to improve performance.  Either the performance of the aging hardware is poor or a handful of VMs are performing bad.

Often customers will chose to do the migration themselves.  I have seen customer use a number of ways to do this from block level storage copy, to un mounting of LUNs from the live system and mounting them to the new system, Copying VM folders, V2V with VMware converter or other third party tools. I have even seen some customers use the old sVmotion script for 3.5 migrations.

However the migration is performed, the outcome from the customer is always the same, initially the system will perform OK but after more VM's are created the performance decreases.  The system is nowhere near the consolidation ratio that was quoted in my capacity planning and the customer becomes unhappy.

So my company will receive a call and we will go and investigate.  What will we find!!!!

1. The migrated workload is badly sized - VM's with 4 CPU's and 8GB of RAM 
2. The migrated workload VM's have version 4 or version 7 hardware 
3. The migrated workload has out of date VM tools
4. The migrated workload is all sitting on the same datastore
5. the migrated workload VMs have reservations and limits configured on the VMs

All of the above my seem simple but they are always the reasons for bad performing V2V Virtual machines.  Often physical migrations have additional problems with post and pre checks, driver removal etc.  But the physical migrations are becoming more and more rare these days.

So one of the most important parts of a vSphere migration in my view is sizing the VMs correctly, often customers dont appreciate that giving VMs more vCPU can have a negative affect on its performance.  I may cover the technical bits as to why this is the case in a later blog.  

HP Flex-10 and VMware

Hi All

         I have recently been doing a full HP Flex-10 installation with VMware and NetApp storage.  Now I have done a few of these in the past and I have always struggled to calculate how the bandwidth should be split between the vNIC's presented to the blades.

There are a few posts out there and all point to gathering customer requirements.  Now most customers when asked this will just say "What do you recommend" and this is what i would expect from most of my customers.  I am a consultant and I should advise them correctly on this as there compleatly new to the concept and technology.

During a full project life cycle this is more than something I am comfortable with.  We would perform a complete capacity planning exercise and in this we could see the existing bandwidth needed by storage and network connectivity, as long as the system was not bottle necking.  However most of these HP Flex-10 projects i seem to get handed are half completed,  the sell and the design has been completed and we are asked to complete the implementation.  Now this is something that I am not a fan of but unfortunately is something that is common in the channel consultancy sector.

So I am sitting infront of the customer and deciding what I should do to carve up the bandwidth.  To be 100% sure is impossible so I decided to use the reference architecture produced by HP for vSphere 4.0.    Located Here

This details the following breakdown.

This makes a lot of sense in what it suggests,

ESXi Management is given a 500Mb Share - VMware beat practise is to dedicate a 2X physical NICs for failover, but VMware do not define a best practise for bandwidth for the Management traffic. Often Customers using physical separation of networks will use a 100Mb switch witch will more than cope with vCenter agent traffic and heartbeat traffic. 

vMotion and Fault tolerance are given a 2.5Gb share - Most of my designs now include these two sitting on the same vSwitch with separate portgroups.  To guarantee the 1GB bandwidth is provided and uninterrupted to both portgroups each port group has an active NIC witch is provided to the other prtgroup as a standby adapter to provide redundancy.  

ISCSI is given 4GB share - This largely depends on the backend storage, what I am trying to say is providing 4Gb bandwidth to the blade is pointless if the backend storage only has 2X 1Gb connections. The sizing in the reference architecture just so happend to tie in with what was configured on the backend of the storage I was using each storage processor had 2X 10Gb connections, and the storage array had 2 storage processors.   

Virtual Machine traffic (multiple Networks) are given a 3Gb Share. - This was the remaining bandwidth and after reviewing some low level perf mon and switch statistics from the existing physical infrastructure, 3Gb was more than enough bandwidth.

Each module has its own defied ethernet network for redundancy, N1 is the first Flex-10 interconnect and N2 is the second Flex-10 interconnect.

Another thing that is important is to make sure you utilise the full bandwidth from each Flex-10,  Configuring the above and using 1X10Gb will cause a bottle neck on the uplink's.  

I will go into to configuration with VMware in another post.  I would also be interested to know if anyone else had any different ways of calculating this?

Back for More......

Ok I have not been on here for a VERY Long time.  Mainly because I have been promoted at work last September :-)  I have been promoted to a Senior Virtualisation Consultant and a SME (Subject matter expert) in VMware vSphere and vCloud Director.

This resulted in me learning a massive amount to make some of the companys processes better and smoother.  One of the responsibilities of my role is to complete all the vSphere designes and oversee all the implementations by Engineers and Consultants.  This has resulted in me doing a massive amount of work, to not just update the company processes but to actually create some!!!

I am responsible for all the design based documentation, All the White papers to keep consultants up to date on how to do things, all the companies standards/best practises as well as blog on the company blog about things wee see in the field.

On top of the above I am still the lead implementation consultant undertaking all the enterprise and high level implementations.

So I have decided to start back on my blog again as there are many things I have been implementing over the last few months, also I am hoping to obtain my VCDX some time in the future.  I am currently studying for my VCAP5-DCD and I will also upgrade my VCAP4-DCA soon as well.

So my next post will be something more exciting.......

New Job

Ok I have been away for a while, mainly due to me starting a new job with a Professional Services channel consultancy. Have been here just over a month now and love it. Much more technical involvement in the projects and I am seeing so much more technology out there.

I am also now booked to take the VCAP-DCA exam again. I failed this the first time due to the computer I was using to take the test locking up every 5 mins for 5 mins. I did however get a voucher to retake, and I did get some feedback from that exam, I ran out of time with 6 questions left and only failed by 6 marks. I didn’t think that was too bad.

I am studying from scratch however and have been setting up my LAB at my new work place. They seem to be fairly impressed and I think I am making a good impression.

Well there is no technical blog to post at the moment but I do have an article on 1:1 NIC teaming for iscsi load balancing that I will be pitting up soon.

Catch you soon.

vCAP-DCA

Hi All
Long time since my last update mainly down to studying for the vCAP-DCA exam. I am afraid the news from the exam is not good. I arrived at my test centre in London and went over all the normal stuff. I sat down and then started the exam.

For obvious reasons I have to watch what i put on here.

The exam started and i set to work. as detailed by many others the exam is a Live Lab, but the problem I had was with the connection to the LAB. It was soo slow and unresponsive and made the exam very tiresome and frustrating. I got about 3/4 into the exam and then ran out of time. I suspect that will result in me having to retake the exam and i am defo not paying for the retake at £300.

I found no questions difficult and if I was unsure VMware do give you all the documentation for all the product sets you are looking at, so I tried to look up a few items that I was unsure about, but due to the problems with the slow LAB I couldn't read the documentation.

I have complained about the LAB and it seems I am not the only one taking it outside the USA who has had this problem.

Going back to the preparation for the exam I found the following sites very helpful in assisting me with preparing for the exam

vFAIL.NET - Brilliant site and the summary of each section is good- However I would always try and look more in depth at each section. Do a quick Google or look for the VMware paper.

KendrickColeman - Is one better then the above and provides a download section containing all the PDFs and web2PDF's that you will need to help you master the section.

Over all I would like to thank both the above, but also have to stress you have to know how to use the more advanced features in a day to day install. Just reading here on how to use the Powershell cmdlets or the vMA is not enough as you will be asked questions that will prove if you know how to use the features.

I am going to chase VMware to see whats happening with my complaint. fingers crossed it is positive.

ESXI Managment / VCAP

Hi All
I have been looking at the management of ESXi over the last few weeks. It would appear there is very little out there on managment of it for advacned administrators such as myself. Most people seem to be content with managing it from vCenter or the console. I have found several times it is not easy to do this and when troubleshooting it dosnt provide much information or assistance.

VMware do have a vMA. This is a basic Linux machine running as a mock service console. It allows you to attache multiple ESX and ESXi machines to it and then manage then using more or less the same commands as you would from the service console in a full ESX install. There are limitations as it is not a service console and is only a collection of scripts that run to mock a service console.

I will be focusing on creating a powershell based management pack for my company in the next couple of weeks. I will not be able to release that on here but I should be able to release a cut down version. I am not sure if I am going to do it in an appliance or as a standalone package. lets see how board I get.

I am also now looking to complete the VMware Certified Advanced Professional exam that has just been released. Will try and relay some helpful study information if I can.

Host currently has no management network redundancy.

Hi All
After a nice holiday I cam back into the office and eased myself back into the flow. I had a small rebuild to conduct from vSphere ESX to vSPhere ESXi U2. Rebuilding the hosts was very simple but after found I was being given this message on the vCenter

Host currently has no management network redundancy.

I could not see any problems as the vmKernal port had 4 vmnics. I reconfigured the HA for each host and then the problem started again.

In the end I looked around and found the following KB from VMware

KB1004700

Details that you can disable this alarm and it is a small glitch in the vCenter .