vSAN license alarm 'vSAN Cluster Claimed Capacity Exceeds Entitlement'

Products

• VMware vSAN

Issue/Introduction

VMware is introducing a free-use tier for the first time for vSAN called "vSAN Trial Capacity". This KB describes how vSAN Trial Capacity may be used and what they need to do if / when the customer exceeds the amount they are allowed to use.

In order for VMware vSphere Foundation (VVF) users to easily try vSAN, VMware is now offering a useful amount of vSAN capacity that can be used for the duration of your vSphere Foundation as long as you do not exceed 100GiB of vSAN capacity per vSAN core.

The user is entitled to use up to 100GiB of vSAN capacity for each vSphere Foundation core that is configured as part of a vSAN cluster.

This capacity can be used without any additional vSAN purchase for the life of the vSphere Foundation subscription as long as the cluster capacity does not exceed 100GiB of capacity per vSAN core.

Note: This capability does not replace the traditional 60 day Evaluation Mode for vSphere and vSAN that has existed for many years.  Evaluation Mode continues to exist to permit 60 day use of an unlimited amount of vSAN while this capability removes the 60 day limit but only for a maximum of 100GiB per core.  See the Comparison of Evaluation Mode/Free Use Entitlement section below for more information.

You are only entitled to use 100GiB for each core in a vSAN cluster and NOT per core of vSphere if that vSphere core is not in a vSAN cluster (see Examples below).

If you already have any vSAN keys applied to the cluster, the vSAN Trial Capacity does not apply.

Note: The vSAN Trial Capacity does not apply within a VMware Cloud Foundation (VCF) based deployment since all VCF purchases are automatically entitled to 1TiB of vSAN capacity for each VCF core.

 

The capacity calculation is based on the physical, raw capacity of the storage devices that are “claimed” or owned by vSAN at the time of the cluster creation.  

If the user configures a vSAN cluster with devices that add-up to a total claimed capacity that exceeds 100GiB per vSAN core, then the admin will be alerted by a vSAN health check to take action to reduce the physical capacity of the cluster or to purchase licenses for the appropriate amount of vSAN capacity.

The capacity alert is triggered only based on the amount of physical capacity configured in the cluster and is independent of any amount of capacity actually used by VMs in the vSAN cluster.

Because the capacity calculation is based entirely on the physical capacity configured in the cluster, it is possible to receive a capacity alert immediately after cluster configuration even if there are no VMs hosted by the cluster.

For example, if you have a 32 core host that includes vSAN storage devices adding up to more than 3.2 TiB (32 cores x 100GiB per core = 32,000 GiB or 3.2 TiB), then you would be exceeding the free use limit.

With the alert, the user will be notified to purchase the amount of vSAN required to fully license the entire total capacity of the cluster, not just the incremental amount that is beyond the 100GiB per core entitlement (see Examples below).

Alternatively, the admin may reconfigure the cluster to reduce the cluster capacity so that it uses 100GiB per vSAN core or less physical capacity.

 

Examples

 

Example 1:  Purchase of 256 cores of vSphere Foundation (VVF), with all of the cores being used for vSAN, in 2 vSAN clusters.

 

• 256 cores of VVF includes 256*100GiB = 25,600 GiB (25.6 TiB) of vSAN free use
• I configure 2 vSAN clusters
• Each cluster has 128 cores and 12.8 TiB (12,800GiB) of capacity
  • Qty 4 32 core hosts
  • Each host has 2x1.6 TiB storage devices (3.2TiB per host)
  • 4 hosts x 3.2 TiB per host = 12.8TiB capacity
• 2 clusters means I will use, in-total…
  • 8 vSAN hosts for a total of 256 cores
  • 25.6TiB of storage
• If more capacity is required than 25.6TiB per cluster above, they must either…
  • Purchase more VVF cores and create a new vSAN cluster… OR…
  • They must purchase additional vSAN capacity to replace the vSAN Trial Capacity capacity and cover the total cluster capacity. 

 

Example 2:  Purchase 256 cores of vSphere Foundation (VVF) but only 128 cores are going to be used for vSAN in a single vSAN cluster.

• 256 cores of VVF includes 256*100GiB = 25,600 GiB (25.6 TiB) of vSAN free use but, in this example, not all cores will be used as vSAN cores and I am only allowed to have 100GiB per core configured as vSAN
• I configure 1 128 core vSAN cluster
• The cluster has 128 cores and 12.8 TiB (12,800GiB) of capacity
  • Qty 4 32 core hosts
  • Each host has 2x1.6 TiB storage devices (3.2TiB per host)
  • 4 hosts x 3.2 TiB per host = 12.8TiB capacity
• For the remaining 128 VVF cores that are not configured as vSAN, they are not entitled to 100GiB per core free use and thus they cannot contribute any capacity to the cluster configured above.
  • That is, you cannot take a 100GiB per core entitlement from a vSphere only (non-vSAN…) core and apply it to a vSAN core to get 200GiB per vSAN core.
• If more capacity is required than 25.6TiB per cluster above, they must either…
  • Create a new vSAN cluster with the VVF cores they purchased… OR…
  • Use the VVF cores they have to add another host to the existing cluster while staying below the 100GiB per vSAN core limit… OR…
  • They must purchase additional vSAN capacity to replace the vSAN Trial Capacity and cover the total cluster capacity. 

 

Example 3:  Purchase 256 cores of vSphere Foundation (VVF), with 1 128 core vSAN cluster, but I need more than 100GiB per vSAN core of capacity.

• 256 cores of VVF includes up to 256*100GiB = 25,600 GiB (25.6 TiB) of vSAN free use
• I also happen to need 25.6TiB of capacity but since I need it in a single cluster with 128 cores, I will exceed the 100GiB per vSAN core that I’m entitled to use with VVF.
  • I am using 2 x 3.2TiB storage devices in each host
• My cluster will look like this…
  • 4 ea. 32 core hosts for a total of 128 cores
    • Each host has 2 x 3.2TiB storage devices for 6.4 TiB per host
    • 4 hosts x 6.4 TiB = 25.6 TiB per cluster
    • 25.6 TiB in a 128 core cluster = 200GiB per core and thus it does not qualify for free use.
    • I'm only allowed free use of up to 128 cores x 100GiB = 12.8TiB in this cluster.
    • I configure 25.6GiB of capacity in the cluster and immediately begin to see vSAN health check alerts telling me I have exceeded my capacity and must apply a vSAN key to be in compliance with my VMware subscriptions.
• Since I need 25.6TiB of capacity, and I must purchase vSAN per TiB, then I round up to purchase a minimum of 26TiB in order to properly license the entire cluster.
• Once you apply the 26TiB key to the cluster, you will no longer see any new alerts indicating you have exceeded 100GiB per core.
• Otherwise, the alerts will continue until a vSAN key is applied.

 

Comparison of Evaluation Mode/vSAN Trial Capacity

 

The vSAN 60 day Evaluation Mode will continue to exist in the vSphere Foundation and VMware Cloud Foundation offerings based on their different capabilities:

 

• vSAN Evaluation Mode:
  • Duration: 60 day maximum before a vSAN key must be applied
  • Capacity limit:  None
  • This is often used for operational activities when there is a temporary need for a vSAN capacity as part of an automated bring-up process or to temporarily duplicate clusters when transitioning from old- to new hardware.
• vSAN Trial Capacity Mode:
  • Duration:  Duration of the vSphere Foundation subscription
  • Capacity limit: Up to 100GiB of vSAN capacity per vSAN core.
  • This is useful for customers who want to run a small amount of vSAN, potentially to get experience before expanding to paid vSAN.

 

Upon cluster creation, the vCenter logic will automatically determine whether to apply Evaluation Mode or the vSAN Trial Capacity Entitlement as-follows:

1. If no key has been applied for either vSphere or vSAN then…
   1. vCenter will assume this is Evaluation Mode
2. If a vSphere Foundation key exists on the hosts at the time of cluster creation, but there is no vSAN key applied, then…
   1. vCenter will assume you wish to use the vSAN Trial Capacity
3. If any vSAN key has been applied, then the vSAN Trial Capacity entitlement does not apply
   1. For example, this would be the case when creating a VCF based cluster where vSAN keys are included with your VCF purchase.

Note that vCenter can dynamically switch between modes. For example…

• If there are no vSphere or vSAN keys, and you are put into Evaluation Mode, then once you apply a vSphere key, then the 60 day limit will be removed and you will be allowed the free use of up to 100GiB per core.

 

Whether you are in Evaluation Mode or vSAN Trial Capacity Mode can be determined by navigating to the vSphere Client Licensing and Subscription UI and viewing the end-date for the cluster.  Evaluation Mode will reflect a 60 day limit while the free use mode will reflect an end date that is typically multiple years away.

Symptoms:
vSAN 8.0 P03
A cluster level vSAN license alarm 'vSAN Cluster Claimed Capacity Exceeds Entitlement' is triggered. Refer the screenshots as below.

Environment

VMware vSAN 8.0.x

Cause

• vSAN cluster claimed capacity exceeds the license entitlement. License entitlement is 100 GB per CPU core.
• If vSAN cluster claimed capacity has exceeded the entitled capacity by more than 100% but less than 110%, a "Warning" alert will be triggered.
• If vSAN cluster claimed capacity has exceeded the entitled capacity by 110%, a "Critical" alert will be triggered

Resolution

Apply a valid vSAN license to the cluster or add more CPU cores by adding new hosts.