Error when expanding cluster - SSD tier on nodes

  • 5 October 2021
  • 2 replies


I am trying to expand my cluster and receiving this error in the UI 


Failure in pre expand-cluster tests. Errors: Failed to start foundation service to do network validation SSD tier on nodes [u'xx.xx.xx.xx', u'xx.xx.xx.xx'] is not sized to accomodate expected metadata growth on cluster. Refer KB-8842 for more details. Cluster has 1 nodes. Cluster expansion from less than 2 nodes not supported


KB-8842 - i run the test outlined in kb-8842 and do not get any errors. Only warnings not related to the cluster expansion.

health_checks run_all

| State         | Count |
| Pass          | 198   |
| Info          | 2     |
| Warning       | 2     |
| Total Plugins | 202   |


It states this and it appears that the ssd is to small.

Using data obtained in the preceding output, look for the nodes with the smallest SSD tier, especially in a heavily skewed cluster. In order to sustain cluster growth, sizing of the SSDs in smaller nodes is of utmost importance.

/dev/sdd1        5678267    78   5620830   1% /home/nutanix/data/stargate-storage/disks/ZAD6LD530000C911
/dev/sda4         420116   257    415574   1% /home/nutanix/data/stargate-storage/disks/S5GBNE0MA00406X
/dev/sdc1        5678267    65   5620842   1% /home/nutanix/data/stargate-storage/disks/ZAD6LEBG0000C913
/dev/sdb1        5678267    66   5620842   1% /home/nutanix/data/stargate-storage/disks/ZAD6LED60000C913

I am trying to install ce-2020.09.16, and it has installed successfully but i can not expand the cluster.


I have 3 servers with the exact same configuration.

ssd = 430GB
hhd - 5TB x 3  (data)


The question is:

Since the error is concerning the size of the SSD, What is the correct sizing of the SSD for this configuration

Is there a sizing matrix that is supported somewhere online?




2 replies

Userlevel 2
Badge +4

@Joe Fong HI,


Here is the link to the recommended Hardware specs for CE.


Hopefully this answers your question.  Let me know.



Userlevel 3
Badge +4

Hi @Joe Fong 


Have you checked the doc that @Michael.Manuele shared?


What i understood from your post (cluster has one node, Cluster expansion from less than 2 nodes not supported) is that you are trying to to expand a CE single node cluster to a CE three node cluster. 


If that statement is correct the docs says:

  • A Community Edition Single-node Cluster is created with redundancy factor 1. You cannot extend an existing single-node cluster to a three- or four-node cluster, to automatically create a cluster with redundancy factor 2. To expand to a three- or four-node cluster when you have a single-node cluster, destroy the cluster first, then create the new cluster. See Destroying a Cluster.


So i’m afraid that you should destroy the single node cluster an then create a new three node cluster