A LOOK INSIDE THE UPCOMING VSPHERE CLUSTERING BOOK
I just received the second proof copy of the new book and I’m really (really) stoked about the book. The full color print is awesome and truly adds that special feeling to the book. I’m so excited how the diagrams turned out, that I must share some pictures of the inside of the book. (For the CSI-fan’s, yes I have blurred some text fields as they contain NDA material) Besides the diagrams, the whole interior is redesigned. The spread is reviewed, inner and outer margins are adjusted and we even taken the gutter space into account, providing a better and nicer reading experience. We decided that we are going to offer the book in Full color format and a (full-color) ebook. After seeing the full-color version, we believe publishing a black and white version will not do the content any justice.And due to time constraints we cannot invest time in offering a black and white version of the book. We are still finalizing the book but we hope to provide the possibility of pre-ordering near the publish date. Stay tuned for more information!
KEEP ALIVE PING - SOME UPDATES
Lately the amount of content of frankdenneman.nl is getting a bit stale, so a small update from my side to show what I’ve been up to and that this blog is still alive. vSphere x Clustering Deepdive Duncan and I are working (feverishly) on a new book for a while. Calling it an update of the 4.1 HA and DRS technical deepdive won’t do the book any justice as the old chapters are complete rewritten. The HA section will cover the new HA stack of the upcoming vSphere version, while the focus of the DRS section leans more towards resource management. In addition this book covers Storage DRS and introduces a cool new feature called “supporting deep dives” These additional deep dives expand on supporting technologies of the main cluster feature set, it will contain in-depth information of technologies such as vMotion, Storage vMotion, EVC and certain new technologies introduced in the upcoming version of vSphere. I bet you guys will love this stuff. Speaking at VMworld 2011 Last Friday I received very good news. In my previous post I asked everyone to consider voting on the sessions I participate in and the good news is that both sessions were accepted. Session VSP1682 - vSphere 5 clustering Q&A, co-presenting with Duncan is accepted for both VMworld Las Vegas as well as VMworld Europe in Copenhagen. The second session, VSP1425 - Ask the Experts vBloggers, I’m proud to join the incredible line-up of Chad Sackac, Duncan Epping, Rick Scherer and Scott Lowe to help answer questions on virtualization design. After 5 years of visit VMworld as an attendee, I finally get to experience what it’s like to be at the other side of the room.
VMWORLD PUBLIC VOTING
VMworld 2011 session voting opened a week ago and there a still a few days left to cast your vote. About 300 in-depth sessions will be presented at VMworld this year and this year two sessions are submitted in which I participate. Both sessions are not the typical PowerPoint slide sessions, but are based on interaction with the attending audience. TA 1682 – vSphere Clustering Q&A Duncan Epping and Frank Denneman will answer any question with regards to vSphere Clustering in this session. You as the audience will have the chance to validate your own environment and design decisions with the Subject Matter Experts on HA, DRS and Storage DRS. Topics could include for instance misunderstandings around Admission Control Policies, the impact of limits and reservations on your environment, the benefits of using Resource Pools, Anti-Affinity Rules Gotchas, DPM and of course anything regarding Storage DRS. This is your chance to ask what you’ve always wanted to know! Duncan and I conducted this very successful session at the Dutch VMUG. Audience participation led to a very informative session where both general principles and in-depth details were explained and misconceptions where addressed. TA1425 - Ask the Expert vBloggers Four VMware Certified Design Experts (VCDX) On Stage! Are you running a virtual environment and experiencing some problems? Are you planning your companies’ Private Cloud strategy? Looking to deploy VDI and have some last minute questions? Do you have a virtual infrastructure design and want it blessed by the experts? Come join us for a one hour panel session where your questions are the topic of discussion! Join the Virtualization Experts, Frank Denneman (VCDX), Duncan Epping (VCDX), Scott Lowe (VCDX) and Chad Sakac, VP-VMware Alliance within EMC, as they answer your questions on virtualization design. Moderated by VCDX #21, Rick Scherer from VMwareTips.com Many friends of the business have submitted great sessions and there are really too many to list them all, but there is one I would want to ask you to vote on and that is the ESXi Quiz Show. A 1956 – The ESXi Quiz Show Join us for our very first ESXi Quiz Show where teams of vExperts and VMware engineers will match expertise on technical facts, trivia related to all VMware ESXi and related products. You as the audience will get 40% of the vote. We will cover topics around ESXi migration, storage, networking security, and VMware products. As an attendee of this session you will get to see the experts battle each other. For the very first time at VMworld you get to decide who leaves the stage as a winner and who does not. This can become the most awesome thing that ever hit VMworld. Can you think about the gossip, the hype and the sensation will introduce during VMworld? As Top vExperts, bloggers, VMware engineers and the just the lone sys admin (no not you Bob Plankers ;) ) compete with each other. Will the usual suspect win or will there be upsets? Who will dethrone who? Really I think this will become the hit of VMworld 2011 and will be the talk of the day at every party during the VMworld week. Session Voting is open until May 18, the competition is very fierce and it’s very difficult to choose between the excellent submitted sessions, however I would like to ask your help and I hope you guys are willing to vote on these three sessions. http://www.vmworld.com/cfp.jspa
CONTENTION ON LIGHTLY UTILIZED HOSTS
Often I receive the question why a virtual machine is not receiving resources while the ESXi host is lightly utilized and is accumulating idle time. This behavior is observed while reviewing the DRS distribution chart or the Host summary tab in the vSphere Client. A common misconception is that low utilization (Low MHz) equals schedule opportunities. Before focusing on the complexities of scheduling and workload behavior, let’s begin by reviewing the CPU distribution chart. The chart displays the sum of all the active virtual machines and their utilization per host. This means that in order to have 100% CPU utilization of the host, every active vCPU on the host needs to consume 100% of their assigned physical CPU (pCPU). For example, an ESXi host equipped with two Quad core CPUs need to simultaneously run eight vCPUs and each vCPU must consume 100% of “their” physical CPU. Generally this is a very rare condition and is only seen during boot storms or incorrect configured scheduled anti-virus scanning. But what causes latency (ready time) during low host utilization? Lets take a closer look at some common factors that affect or prohibit the delivery of the entitled resources:
RESTART VCENTER RESULTS IN DRS LOAD BALANCING
Recently I had to troubleshoot an environment which appeared to have a DRS load-balancing problem. Every time when a host was brought out of maintenance mode, DRS didn’t migrate virtual machines to the empty host. Eventually virtual machines were migrated to the empty host but this happened after a couple of hours had passed. But after a restart of vCenter, DRS immediately started migrating virtual machines to the empty host. Restarting vCenter removes the cached historical information of the vMotion impact. vMotion impact information is a part of the Cost-Benefit Risk analysis. DRS uses this Cost-Benefit Metric to determine the return on investment of a migration. By comparing the cost, benefit and risks of each migration, DRS tries to avoid migrations with insufficient improvement on the load balance of the cluster. When removing the historical information a big part of the cost segment is lost, leading to a more positive ROI calculation, which in turn results in a more “aggressive” load-balance operation.
KINDLE VERSION OF HA&DRS BOOK AND INFO ON AMAZON'S REGIONAL PRICE SCHEME
Maybe you already seen the tweets flying by, seen the posts on Facebook or just heard it at the water cooler but we finally published the eBook (Kindle) version of the HA and DRS deepdive book. Duncan has the low down on how the eBook came to life: http://www.yellow-bricks.com/2011/04/05/what-an-ebook-is-this-a-late-april-fools-joke/. We know that many who wanted the eBook bought the paper version instead so we decided to make it cheap and are offering the book for only $7.50. Please be aware that Amazon is using a regional price scheme, so orders outside the US pay a bit more. However, Marcel van den Berg (@marcelvandenber) posted a workaround how to save some money. Disclaimer: we do guarantee this works and won’t support this in any form. So without further ado we present: vSphere 4.1 HA and DRS technical deepdive,. Pick it up. Duncan & Frank PS: it is also available in the UK Kindle Store for £5.36.
KINDLE VERSION OF HA&DRS BOOK AND INFO ON AMAZON'S REGIONAL PRICE SCHEME
Maybe you already seen the tweets flying by, seen the posts on Facebook or just heard it at the water cooler but we finally published the eBook (Kindle) version of the HA and DRS deepdive book. Duncan has the low down on how the eBook came to life: http://www.yellow-bricks.com/2011/04/05/what-an-ebook-is-this-a-late-april-fools-joke/. We know that many who wanted the eBook bought the paper version instead so we decided to make it cheap and are offering the book for only $7.50. Please be aware that Amazon is using a regional price scheme, so orders outside the US pay a bit more. However, Marcel van den Berg (@marcelvandenber) posted a workaround how to save some money. Disclaimer: we do guarantee this works and won’t support this in any form. So without further ado we present: vSphere 4.1 HA and DRS technical deepdive,. Pick it up. Duncan & Frank PS: it is also available in the UK Kindle Store for £5.36.
FULL COLOR VERSION OF THE NEW BOOK?
If you are following us on twitter you may have seen some recent tweets regarding our forthcoming book. Duncan (@duncanyb) and I have already started work on a new version of the HA and DRS Technical Deepdive. The new book will cover HA and DRS topics for the upcoming vSphere release. We are also aiming to include information about SIOC and Storage DRS in this version. We received a lot of feedback about the vSphere 4.1 book, one of the main themes was the lack of color in the diagrams. We plan to use a more suitable grayscale color combination in the next version, but we wondered if our readers would be interested in a full color copy of the upcoming book. Obviously printing costs increase with full color printing and in addition, low volume cost of color printing can be quite high. We expect the price of the full color version to cost around $50 USD – $55 USD. [poll id=“1”]
IP-HASH VERSUS LBT
vSwitch configuration and load-balancing policy selection are major parts of a virtual infrastructure design. Selecting a load-balancing policy can have impact on the performance of the virtual machine and can introduce additional requirements at the physical network layer. Not only do I spend lots of time discussing the various options during design sessions, it is also an often discussed topic during the VCDX defense panels. More and more companies seem to use IP-hash as there load balancing policy. The main argument seems to be increased bandwidth and better redundancy. Even when the distributed vSwitch is used, most organizations still choose IP-hash over the new load balancing policy “Route based on physical NIC load”. This article compares both load-balancing policies and lists the characteristics, requirements and constraints of both load-balancing policies. IP-Hash The main reason for selecting IP-Hash seems to be increased bandwidth as you aggregate multiple uplinks, unfortunately adding more uplinks does not proportionally increase the available bandwidth for the virtual machines. How IP-Hash works Based on the source and destination IP address together the VMkernel distributes the load across the available NICs in the vSwitch. The calculation of outbound NIC selection is described in KB article 1007371. To calculate the IP-hash yourself convert both the source and destination IP-addresses to a Hex value and compute the modulo over the number of available uplinks in the team. For example Virtual Machine 1 opens two connections, one connection to a backup server and one connection server to an application server.
DUTCH VBEERS
Simon Long of The SLOG is introducing vBeers to Holland. I’ve copied the text from his vBeers blog article. Every month Simon Seagrave and I try organise a social get together of like-minded Virtualization enthusiasts held in a pub in central London (and Amsterdam). We like to call it vBeers. Before I go on, I would just like to state, although it’s called vBeers, you do NOT have to drink beer or any other alcohol for that matter. This isn’t just an excuse to get blind drunk. We came up with idea whilst on the Gestalt IT Tech Field Day back in April. We were chatting and we both recognised that we don’t get together enough to catch-up, mostly do to busy work schedules and private lives. We felt that if we had a set date each month, the likely hood of us actually making that date would be higher than previous attempts. So the idea of vBeers was born.