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Sizer Extent Store and Actual Container Size

  • 13 January 2019
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Can anybody confirm if the Extent Store size shown in the Nutanix Sizer tool will be equal to the Container Maximum Capacity that can be used by the VMs for data storage?

I am designing a 3-node cluster with following Disks
3 * 960 GB SSD
6 * 4 TB HDD

Nutanix Sizer shows Extent Store (Assuming RF2) = 9.63 TiB for HDD and 0.64 TiB for SSD
The total shown is 10.27. Will this value be the Maximum Capacity available for the Container to be made out of storage pool?

As I have observed the Container Maximum Capacity is exactly half of what the Storage Pool Capacity is shown. What will be the Storage Pool Capacity shown for the above mentioned specs and is this value visible in Nutanix Sizer tool/Storage Capacity Calculator?
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Best answer by manfred 14 January 2019, 12:24

HI Muhammad,

The (max) storage container capacity is SIZE of Storage Pool divided by RF.
And yes: the output for effective capacity (RFx) is the container max. capacity.
Please also take into consideration the failover capacity: if you have more than 6,9 TB used it cannot tolerate a node failure anymore.
Also please note that there may be some small differences between the sizer output and your planned cluster environment.
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HI Muhammad,

...Please also take into consideration the failover capacity: if you have more than 6,9 TB used it cannot tolerate a node failure anymore....

Hello Manfred,

About this, my understanding is that the cluster will not be able to reconstruct the RF2 policy for all data in the two remaining nodes (because they're already full), so if the 3rd node doesn't come back online, the cluster will remain degraded (but with all data still available, just some of it will only have a single copy). Is this interpretation correct or does the cluster lose data?
Userlevel 2
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Even when you have 2 nodes nutanix will try to rebuild data when you have enough capacity available.
Userlevel 2
Badge +7
HI Muhammad,

The (max) storage container capacity is SIZE of Storage Pool divided by RF.
And yes: the output for effective capacity (RFx) is the container max. capacity.
Please also take into consideration the failover capacity: if you have more than 6,9 TB used it cannot tolerate a node failure anymore.
Also please note that there may be some small differences between the sizer output and your planned cluster environment.

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