Project #vGiveback

It is VMworld again, and just like last year VMware decided to give back to the community. No I am not talking about the virtualization community, but I am talking about charity, the great thing is that just like last year you can get VMware to give away an X amount to a charity cause of your choice (health, children, education or environment). As a friend of the VMware foundation I would like to ask ALL of you to help. So what do you need to do, what is the goal?

Well it is simple. Publish a picture on either Instagram or Twitter. Make sure the picture represents the cause and of course you need to tag it, use #vGiveBack and copy in @vmwFoundation. Your message should look like something like this:

(Causes can be: #health #children #education or #environment)

The goal is 10,000 photos between Monday, August 31st and Thursday, September 3rd, out of which a mosaic will be crated. The final image for the mosaic symbolizes our community impact, and once complete, unlocks a donation that will be divided in proportion to the causes you select.

So what am I asking?

  1. Post a picture on twitter or instagram with the right hashtags and make copy in @vmwFoundation (it doesn’t need to be in front of one of those signs by the way, it can be a different pic…)
  2. Ask all of your friends to do the same, we need to hit that number lets make this go viral!

Every little bit will help. Each tweet or instagram post will bring us one step closer to unlocking our collective impact. If you don’t have twitter or instagram, ask your wife/son/daughter/friend to post for you!

Virtual SAN Ready Nodes taking charge!

Yes that is right, Virtual SAN Ready Nodes are taking charge! As of today when you visit the VMware Compatibility Guide for Virtual SAN it will all revolve around Virtual SAN Ready Nodes instead of individual components. You may ask yourself why that is, well basically because we want to make it easier for you to purchase the hardware needed while removing the complexity of selecting components. This means that if you are a Dell customer and want to run Virtual SAN you can simply select Dell in the VMware Compatibility Guide and then look at the different models there are of the different sizes. It is very easy as can be seen in the screenshot below.

virtual san ready nodes

Traditionally there were 3 different sizes for “Server Virtualization”, but¬†with the full overhaul of the VSAN VCG a new size was added. The naming of the sizing has also changed. Let me explain what it looks like now, note that these “sizing profiles” are the same across all vendors so comparing HP to Dell or IBM (etc) was never easier!

New NameOld Name
HY-2Hybrid Server Low
HY-4** new **
HY-6Hybrid Server Medium
HY-8Hybrid Server High
HY-8Hybrid VDI Linked Clones
Hybrid VDI Full Clones
AF-6All Flash Server Medium
AF-8All Flash Server High
AF VDI Linked Clones
AF VDI Full Clones

The new model introduced is HY-4 Series, the reason this model was introduced is because some customers felt that the price difference between HY-2 and H&-6 was too big. By introducing a model in between we now cover all price ranges. Note that it is still possible when selecting the models to make changes to the configuration. If you want model HY-2 with an additional 2 disks, or with 128GB of memory instead of 32GB then you can simply request this.

So what are we talking about in terms of capacity etc? Of course this is all documented and listed on the VCG as well, but let me share it with you here also for your convenience. Note that performance and VM numbers may be different for your scenario, this of course will depend on your workload and the size of your VMs etc.

ModelCPU / MemStorage CapStorage PerfVMs per node
HY-21 x 6 core / 32GB2TB4000 IOPSUp to 20
HY-42 x 8 core / 128GB4TB10K IOPSUp to 30
HY-62 x 10 core / 256GB8TB20K IOPSUp to 50
HY-82 x 12 core / 348GB12TB40K IOPSUp to 100
AF-62x12 core / 256GB8TB50K IOPSUp to 60
AF-82x12 core / 348GB12TB80K IOPSUp to 120

In my opinion, this new “Ready Node” driven VMware Compatibility¬†Guide driven approach is definitely 10 times easier then focusing on individual components. You pick the ready node that comes close to what you are looking for, provide your OEM with the SKU listed and tell them about any modifications needed in terms of CPU/Mem or Disk Capacity. PS: If you want to access the “old school HCL” then just click on the “Build Your Own based on Certified Components” link on the VCG page.

Tintri announces all-flash storage device and Tintri OS 4.0

Last week I had the pleasure of catching up with Tintri. It has been a while since I spoke with them, but I have been following them from the very start. I met up with them in Mountain View a couple of times when it was just a couple of guys on a rather empty floor with a solution that sounded really promising. Tintri’s big thing is simplicity if you ask me.¬†Super simple to setup, really easy to manage, and providing VM granular controls for about everything you can imagine. The solution comes in the form of a hybrid storage device (disks and flash) which is served up to the hypervisor as an NFS mount.

Today Tintri announces that they will be offering an all-flash system next to their hybrid systems. When talking to Kieran he made it clear that the all-flash system would probably be only for a subset of their customers. The key reason for this being that the hybrid solution already brings great performance and is at a much lower cost of course. The new all-flash model is named VMstore T5000 and comes in two variants: T5060 and T5080. The T5060 can hold up to 2500 VMs and around 36TB with dedupe and compression. For the T5080 that is 5000 VMs and around 73TB. Both delivered in a 2U form factor by the way. The expected use case for the all flash systems is large persistent desktops and multi TB high performance databases. Key thing here is of course not jus the number of IOPS it can drive, but the consistent low latency it can deliver.

Besides the hardware, there is also a software refresh. Tintri OS 4.0 and¬†Global Center 2.1 are being announced. Tintri OS 4.0 is what is sitting on the VMstore storage systems and Global Center is their central management solution. With the 2.1 release Global Center now supports up to 100.000 VMs. It allows you to centrally manage both Tintri’s hybrid and all-flash systems from one UI and¬†smart things like informing you when a VM is provisioned to the wrong storage system (hybrid but performance wise requires all-flash for instance). Not just inform you, but it also has the ability to migrate the VM from storage system to storage system. Note that during the migration all aspects that were associated with it (QoS, Replication etc) is kept. (Not unlike Storage DRS, but in this case the solution is aware of all that happens on the storage system)¬†What I liked personally about Global Center is the performance views / health views. It is very easy to see what the state of your environment is, where latency is coming from etc. Also, if you need to configure things like QoS, replication or snapshotting for multiple VMs you can do this from the Global Center console by simply grouping them as show in the screenshot below.

Tintri¬†QoS was demoed during the call, and I found this also particularly interesting as it allows you to define QoS on a VM (or VMDK) granular level. When you do things like specifying an IOPS limit it is good to know that Tintri normalizes the IOPS based on the size of the IO. Simply said, all IO of 8KB or lower becomes 1 normalized IOPS, an IO which is 16KB will be 2 normalized IOPS etc. This to ensure fairness in environments (this will be almost every environment) where IO sizes greatly vary. Those whom have ever tried to profile their workloads will know why this is important. What I’ve always like about Tintri is¬†their monitoring things like latency for instance how they split that up in hypervisor, network and storage is very useful. They have done an excellent job again for QoS management.

Last but not least Tintri introduces Tintri VMstack. Basically their converged offering where Compute + Storage + Hypervisor is bundled and delivered as a single stack to customers. It will provide you the choice of storage platform (well needs to be Tintri of course), hypervisor, compute and network infrastructure. It can also include things like OpenStack or the vRealize Suite. Personally I think this is a smart move, but this is something I would have preferred to have seen launched 12-18 months ago. Nevertheless, it is a good move.

Using VM-Host rules without DRS enabled

This week I was playing with the VM-Host rules in my environment. In this particular environment I had DRS disabled and I noticed some strange things when I created the VM-Host rules. I figured it should all work in a normal way as I was always told that VM/Host rules can be configured without DRS being enabled. And from a “configuration” perspective that is correct. However there is a big caveat here, and lets look at the two options you have when creating a rule namely “should” and “must”.

When using a VM-Host “must” rule when DRS is disabled it all works as expected. When you have the rule defined then you cannot place the VM on a host which is not within the VM-Host group. You cannot power it on on those hosts, no vMotion and HA will not place the VM there either after a failure. Everything as expected.

In the case of a VM-Host “should” rule when DRS is disabled this is different! When you have a should rule defined and DRS is disabled then vCenter will allow you to power on¬†a VM on a host which is not part of the rule. HA will restart VMs on hosts as well which are not part of the rule, and you can migrate a VM to one of those hosts. All of this without a warning that the host is not in the rule and that you are violating the rule. Even after explicitly defining an alarm I don’t see anything triggered. The alarm by the way is called “VM is violating a DRS VM-Host affinity rule”.

I reached out to the HA/DRS engineering team and asked them why that is. It appears the logic for the “should” rule, in contrary to the “must rule, is handled by DRS. This includes the alerting. It makes sense to a certain extent, but it wasn’t what I expected. ¬†So be warned, if you don’t have DRS enabled, “VM-Host should rules” will not work. Must rules however will work perfectly fine. (Yes, I’ve asked them to look in to this and fix it so it behaves as you would expect it to behave and come with a warning when you try anything that violates a should rule.)


Virtual SAN going offshore

Over the last couple of months I have been talking to many Virtual SAN customers. After having spoken to so many customers and having heard many special use cases and configurations I’m not easily impressed. I must say that half way during the conversation with Steffan Hafnor R√łstvig from TeleComputing I was seriously impressed. Before we get to that lets first look at the background of Steffan Hafnor R√łstvig and TeleComputing.

TeleComputing¬†is¬†one of the oldest service providers in Norway. They started out as an ASP with a lot of Citrix expertise. In the last years they’ve evolved more to being a¬†service provider rather than an application provider.¬†Telecomputing‚Äôs customer base consists of more than 800 companies and in excess of 80,000 IT users. Customers are typically between 200-2000 employees, so significant companies. In the Stavanger region a significant portion of the customer base is in the oil business or delivering services to the Oil business. Besides managed services, TeleComputing also has their own datacenter they manage and host services in for customers.

Steffan is a¬†solutions architect but started out as a technician. He told me he¬†still does a lot of hands-on, but besides that also supports sales / pre-sales when needed. The office he is in has about 60 employees. And Steffan’s core responsibility is virtualization, mostly VMware based! Note that TeleComputing is much larger than those 60 employees, they have about 700 employees worldwide with offices in Norway, Sweden and Russia.

Steffan told me he got first introduced to Virtual SAN when it was just launched. Many of their offshore installation used what they call “datacenter in a box” solution which was based on IBM Bladecenter. Great solution for that time but there were some challenges with it. Cost was a factor, rack size but also reliability. Swapping parts isn’t always easy either and that is one of the reasons they started exploring Virtual SAN.

For Virtual SAN they are not using blades any longer but instead switched to rack mounted servers. Considering the low number of VMs that are typically¬†running in these offshore environments a fairly “basic” 1U server can be used. With 4 hosts you will now only take up 4U , instead of the 8 or 10U a typical blade system requires. Before I forget, the hosts itself are Lenovo¬†x3550 M4’s with one S3700 Intel SSD of 200GB and 6 IBM 900GB 10K RPM drives. Each host has 64GB of memory and two Intel E5-2630 6 core CPUs. It also uses an M5110 SAS controller.¬†Especially in the type of environments they support this is very important, on top of that the cost is significantly lower for 4 rack mounts vs a full bladecenter. What do I mean with type of environments? Well as I said offshore, but more specifically Oil Platforms! Yes, you are reading that right, Virtual SAN is being used on Oil Platforms.

For these environments 3 hosts are actively used and a 4th host is just there to serve as a “spare”. If anything fails in one of the hosts the components can easily be swapped, and if needed even the whole host could be swapped out. Even with a spare host the environment is still much cheaper than compared to the original blade architecture. I asked Steffan if these deployments were used by staff on the platform or remotely. Steffan explained that staff “locally” can only access the VMs, but that TeleComputing manages the hosts, rent-an-infrastructure or infrastructure as a service is the best way to describe it.

So how does that work? Well they use a central vCenter Server in their datacenter and added the remote Virtual SAN clusters connected via a satellite connection. The virtual infrastructure as such is completely managed from a central location. Not just virtual, also the hardware is being monitored. Steffan told me they use the vendor ESXi image and as a result gets all of the hardware notification within vCenter Server, single pane of glass when you are managing many of these environments like these is key. Plus it also eliminates the need for a 3rd party hardware monitoring platform.

Another thing I was interested in was knowing how the hosts were connected, considering the special location of the deployment I figured there would be constraints here. Steffan mentioned that 10GbE is very rare in these environments and that they have standardized on 1GbE. Number of connection is even limited and today they have 4 x 1GbE per server of which 2 are dedicated to Virtual SAN. The use of 1GbE wasn’t really a concern, the number of VMs is typically relatively low so the¬†expectation was (and testing and production has confirmed) that 2 x 1GbE would suffice.

As we were wrapping up our conversation I asked Steffan what he learned during the design/implementation, besides all the great benefits already mentioned. Steffan said that they learned quickly how critical the disk controller is and that you need to pay attention to which driver you are using in combination with a certain version of the firmware. The HCL is leading, and should be strictly adhered to. When Steffan started with VSAN the Healthcheck plugin wasn’t released yet unfortunately as that could have helped with some of the challenges. Other caveat that Steffan mentioned was that when single device RAID-0 sets are being used instead of passthrough you need to make sure to disable write-caching. Lastly Steffan mentioned the importance of separating traffic streams when 1GbE is used. Do not combine VSAN with vMotion and Management for instance.¬†vMotion by itself can easily saturate a 1GbE link, which could mean it pushes out VSAN or Management traffic.

It is fair to say that this is by far the most exciting and special use case I have heard for Virtual SAN. I know though there are some other really interesting use cases out there as I have heard about installations on cruise ships and trains as well. Hopefully I will be able to track those down and share those stories with you. Thanks Steffan and TeleComputing for your time and great story, much appreciated!