Tag Archives: NoSAN

Solving Oracle & SQL Licensing challenges with Nutanix

Posted on by
Reply

The Nutanix platform has and will continue to evolve to meet/exceed the ever increasing customer and application requirements while working within constraints such as licensing.

Two of the most common workloads which I work frequently with customers to design solutions around real or perceived licensing constraints are Oracle and SQL.

In years gone by, Nutanix solutions were constrained to being built around a limited number of node types. When I joined in 2013 only one type existed (NX-3450) which limited customers flexibility and often led to paying more for licensing than a traditional 3-tier solution.

With that said, the ROI and TCO for the Nutanix solutions back then were still more often than not favourable compared to 3-tier but these days we only have more and more good news for prospective and existing customers.

Nutanix has now rounded out the portfolio with the introduction of “Compute Only” nodes to target a select few niche workloads with real or perceived licensing and/or political constraints.

Compute only nodes compliment the traditional HCI nodes (Compute+Storage) as well as our unique Storage Only Nodes which were introduced in mid 2015.

So how do Compute Only nodes help solve these licensing challenges?

In short, Oracle leads the world in misleading and intimidating customers into paying more for licensing than what they need to. One of the most ridiculous claims is “You must license every physical CPU core in your cluster because Oracle could run or have ran on it”.

The below tweet makes fun of Oracle and shows how ridiculous their claim that customers need to license every node in a cluster (which I’ve never seen referenced in any actual contract) is.

So let’s get to how you can design a Nutanix solution to meet a typical Oracle customer licensing constraint while ensuring excellent Scalability, Resiliency and Performance.

At this stage we now assume you’ve given your first born child and left leg to Oracle and have subsequently been granted for example 24 physical core licenses from Oracle, what next?

If we we’re to use HCI nodes, some of the CPU would be utilised by the Nutanix Controller VM (CVM) and while the CVM does add a lot of value (see my post Cost vs Reward for the Nutanix Controller VM) you may be so constrained by licensing that you want to maximise the CPU power for just Oracle workloads.

Now in this example, we have 24 licensed physical cores, so we could use two Compute Only nodes using an Intel Gold 6128 [6 cores / 3.4 GHz] / 12 cores per server for 24 total physical cores.

Next we would assess the storage capacity, resiliency and performance requirements and decide how many and what configuration storage only nodes are required.

Because Virtual Machines cannot run on storage only nodes, the Oracle Virtual Machines cannot and will never run on any other CPU cores other than the two Compute Only nodes therefore you would be in compliance with your licensing.

The below is an example of what the environment could look like.

2CO_4SOnodes

SQL has ever changing CPU licensing models which in some cases are licensed by server or vCPU count, Compute Only can be used in the same way I explained above to address any SQL licensing constraints.

What about if I need to scale storage capacity and/or performance?

You’re in luck, without any modifications to the Oracle workloads, you can simply add one or more storage only nodes to the cluster and it will almost immediately increase capacity, performance and resiliency!

I’ve published an example of the performance improvement by adding storage only nodes to a cluster in an article titled Scale out performance testing with Nutanix Storage Only Nodes which I wrote back in 2016.

In short, the results show by doubling the number of nodes from 4 to 8, the performance almost exactly doubled while delivering low read and write latency.

What if you’ve already invested in Nutanix HCI nodes (example below) and are running Oracle/SQL or any other workloads on the cluster?

TypicalHCIcluster

Nutanix provides the ability to convert a HCI node into a Storage Only node which results in preventing Virtual Machines from running on that node. So all you need to do is add two or more Compute Only nodes to the cluster, then mark the existing HCI nodes as Storage Only and the result is shown below.

CO_PlusConvertedHCI

This is in fact the minimum supported configuration for Compute Only Environments to ensure minimum levels of resiliency and performance. For more information, check out my post “Nutanix Compute Only Minimum requirements“.

Now we have two nodes (Compute Only) which can run Virtual Machines and four nodes (HCI nodes converted to Storage Only) which are servicing the storage I/O. In this scenario, if the HCI nodes have unused CPU and/or RAM the Nutanix Controller VM (CVM) can also be scaled up to drive higher performance & lower latency.

Compute Only is currently available with the Nutanix Next Generation Hypervisor “AHV”.

Now let’s cover off a few of the benefits of running applications like Oracle & SQL on Nutanix:

  1. No additional Virtualization licensing (AHV is included when purchasing Nutanix AOS)
  2. No rip and replace for existing HCI investment
  3. Unique scale out distributed storage fabric (ADSF) which can be easily scaled as required
  4. Storage Only nodes add capacity, performance and resiliency to your mission critical workloads without incurring additional hypervisor or application licensing costs
  5. Compute Only allows scale up and out of CPU/RAM resources where applications are constrained by ONLY CPU/RAM and/or application software licensing.
  6. Storage Only nodes can also provide functions such as Nutanix Files (previously known as Acropolis File Services or AFS)

As a result of Nutanix now having HCI, Storage Only and Compute Only nodes, we’re now entering the time where Nutanix can truely be the standard platform for almost any workload including those with non technical constraints such as political or application licensing which have traditionally been at least perceived to be an advantage for legacy SAN products.

The beauty of the Nutanix examples above is while they look like a traditional 3-tier, we avoid the legacy SAN problems including:

1. Rip and Replace / High Impact / High Risk Controller upgrades/scalability
2. Difficulty in scaling performance with capacity
3. Inability to increase resiliency without adding additional Silos of storage (i.e.: Another dual controller SAN)

With Compute Only being supported by AHV, we also help customers avoid the unnecessary complexity and related operational costs of managing ESXi deployments which have become increasingly more complex over time without significantly improving value to the average customer who simply wants high performance, resilient and easy to manage virtualisation solution.

But what about VMware ESXi customers?

Obviously moving to AHV would be ideal but for those who cannot for whatever reasons can still benefit from Storage Only nodes which provide increased storage performance and resiliency to the Virtual machines running on ESXi.

Customers can run ESXi on Nutanix (or OEM / Software Only) HCI nodes and then scale the clusters performance/capacity with AHV based storage only nodes, therefore eliminating the need to license both ESXi and Oracle/SQL since no virtual machine will run on these nodes.

How does Nutanix compare to a leading all flash array?

For those of you who would like to see a HCI only Nutanix solution have better TCO as well as performance and capacity than a leading All Flash Array, checkout A TCO Analysis of Pure FlashStack & Nutanix Enterprise Cloud where even with giving every possible advantage to Pure Storage, Nutanix still comes out on top without data reduction assumptions.

Now consider that Nutanix the TCO as well as performance and capacity was better than a leading All Flash Array with only HCI nodes, imagine the increased efficiency and flexibility by being able to mix/match HCI, with Storage Only and Compute only.

This is just another example of how Nutanix is eliminating even the corner use cases for traditional SAN/NAS.

For more information about Nutanix Scalability, Resiliency and Performance, checkout this multi-part blog series.

Ignore the nonsense on twitter, What does “NoSAN” mean?

Posted on by
8

Every now and again I see nonsense on twitter which I feel needs to be responded too. The reason I am responding today is to correct mis-information about what Nutanix NoSAN is.

Earlier today a competitor of Nutanix tweeted the following:

FudSlinger

I responded to the above with the following tweet:

mytweet

To which the person responded with this:FudSlinger2

I responded with the below and the conversation ended with the following tweet:FudSlinger3

 

So before I correct the mis-information, let me briefly explain what “SAN” is:

“SAN” or “Storage Area Network” describes the connectivity between a compute node and a storage device (such as a central storage array or disk system). You can for example buy SAN (or FC) Switch/es from companies like Brocade.

However the I.T industry has for whatever reason over the years has made “SAN” mean “Central Disk System / Storage array” so for the purpose of this post, “SAN” is a Traditional Centralized Storage array (SAN/NAS).

So let’s correct the mis-information:

Claim 1: With Nutanix there is a SAN that is auto managed.

Fact: There is no centralized storage with Nutanix

Nutanix software running NDFS (Nutanix Distributed File System) logically presents DAS storage as shared storage across 3 or more nodes via NFS or SMB 3.0 to ESXi, Hyper-V or KVM. Note: While Nutanix supports iSCSI, its not recommended as it creates unnecessary complexity and has no technical advantages.

All Nutanix nodes have local DAS storage which is presented logically as shared storage and there is no “central” Nutanix nodes.

Note: Nutanix nodes can connect to traditional central SAN/NAS storage (see : Can I use my existing SAN/NAS storage with Nutanix)  but this is not Nutanix native architecture.

SAN’s also have key characteristics such as Zoning, Masking, LUNs, RAID, SANs also typically use Fibre Channel (FC) connectivity over dedicated fabrics although this is not always the case.

With Nutanix, There is no:

1. Central storage (SAN or NAS based)
2. LUNs
3. LUN masking
4. Zoning
5. Storage Controller “Pairs”
6. Dedicated Storage Fabric
7. Silos of storage capacity
8. RAID

Therefore the statement about Nutanix being a SAN that is “auto managed” is simply incorrect.

If a SAN “auto manages” LUNs, Zoning, Masking etc its just a smarter SAN, the problems with SAN (and NAS) cannot be solved by simply “masking” the complexity. (Pun intended)

Claim 2: NDFS is a distributed storage array.

Fact: NDFS is a file system, not a storage array.

Nutanix Distributed File System (NDFS) makes up part of the Nutanix solution, it is not a storage array and it is not centralised storage either.

Nutanix is a scale out shared nothing platform where data is written locally where the VM is running and in a distributed (not centralized) manner across nodes.

So what does NoSAN mean to me?

1. No centralized storage array
2. No LUNs, Zoning , Masking , RAID
3. No dedicated storage fabric (e.g.: Fibre Channel Switches)
4. Reduced complexity
5. No Silos of capacity
6. No Storage Controller “Pairs”

I could go on but I think you get the point.

In conclusion, don’t believe what you hear on social media (especially from competitors of a product) and do your own research and validate your findings from multiple sources.

How to Architect a VSA , Nutanix or VSAN solution for >=N+1 availability.

Posted on by
1

How to architect a VSA, Nutanix or VSAN solution for the desired level of availability (i.e.: N+1 , N+2 etc) is a question I am asked regularly by customers and contacts throughout the industry.

This needs to be addressed in two parts.

1. Compute
2. Storage

Firstly, Compute level resiliency, As a cluster grows, the chances of a failure increases so the percentage of resources reserved for HA should increase with the size of the cluster.

My rule of thumb (which is quite conservative) is as follows:

1. N+1 for clusters of up to 8 hosts
2. N+2 for clusters of >8 hosts but <=16
3. N+3 for clusters of >16 hosts but <=24
4. N+4 for clusters of >24 hosts but <=32

The above is discussed in more detail in : Example Architectural Decision – High Availability Admission Control Setting and Policy

The below table highlights in Green my recommended HA percentage configuration based on the cluster size, up to the current vSphere limit of 32 nodes.

HApercentages

Some of you may be thinking, if my Nutanix or VSAN cluster is only configured for RF2 or FT1 for VSAN, I can only tolerate one node failure, so why am I reserving more than N+1.

In the case of Nutanix, after a node failure, the cluster can restore itself to a fully resilient state and tolerate subsequent failures. In fact, with “Block Awareness” a full 4 node block can be lost (so an N-4 situation) which if this is a requirement, needs to be considered for HA admission control reservations to ensure compute level resources are available to restart VMs.

Next lets talk about the issue perceived to be more complicated, Storage redundancy.

Storage redundancy for VSA, Nutanix or VSAN is actually not as complicated as most people think.

The following is my rule of thumb for sizing.

For N+1 , Ensure you have enough capacity remaining in the cluster to tolerate the largest node failing.

For N+2, Ensure you have enough capacity remaining in the cluster to tolerate the largest TWO nodes failing.

The examples below discuss Nutanix nodes and their capacity, but the same is applicable to any VSA or VSAN solution where multiple copies of data is kept for data protection, as opposed to RAID.

Example 1 , If you have 4 x Nutanix NX3060 nodes configured with RF2 (FT1 in VSAN terms) with 2TB usable per node (as shown below), in the event of a node failure, 2TB is no longer available. So the maximum storage utilization of the cluster should be <75% (6TB) to ensure in the event of any node failure, the cluster can be restored to a fully resilient state.

4node3060

Example 2 , If you have 2 x Nutanix NX3060 nodes configured with RF2 (FT1 in VSAN terms) with 2TB usable per node and 2 x Nutanix NX6060 nodes with 8TB usable per node (as shown below), in the event of a NX6060 node failure, 8TB is no longer available. So the maximum storage utilization of the cluster should be 12TB to ensure in the event of any node failure (including the 8TB nodes), the cluster can be restored to a fully resilient state.

4nodemixed

For environments using Nutanix RF3 (3 copies of data) or VSAN (FT2) the same rule of thumb applies but the usable capacity per node would be lower due to the increased capacity required for data protection.

Specifically for Nutanix environments, the PRISM UI shows if a cluster has sufficient capacity available to tolerate a node failure, and if not the following is displayed on the HOME screen and alerts can be sent if desired.

CapacityCritical

In this case, the cluster has suffered a node failure, and because it was sized suitably, it shows “Rebuild Capacity Available” as “Yes” and advises an “Auto Rebuild in progress” meaning the cluster is performing a fully automated self heal. Importantly no admin intervention is required!

If the cluster status is normal, the following will be shown in PRISM.

CapacityOK

In summary: The smaller the cluster the higher the amount of capacity needs to remain unused to enable resiliency to be restored in the event of a node failure, the same as the percentage of resources reserved for HA in a traditional compute only cluster.

The larger the cluster from both a storage and compute perspective, the lower the unused capacity is required for HA, so as has been a virtualization recommended practice for years….. Scale-out!

Related Articles:

1. Scale Out Shared Nothing Architecture Resiliency by Nutanix

2. PART 1 – Problems with RAID and Object Based Storage for data protection

3. PART 2 – Problems with RAID and Object Based Storage for data protection