# Data Object - VsanPerfNodeInformation(vim.cluster.VsanPerfNodeInformation)

Property of
  VsanPerfsvcHealthResult
Returned by
  VsanPerfQueryNodeInformation
Extends
  DynamicData
See also
  LocalizedMethodFault, VsanPerfMasterInformation
Since
  vSphere API 5.5

## Data Object Description

Runtime information about the vSAN Performance service of a single vSAN host.
CMMDS master
The Cluster Monitoring, Membership, and Directory Service (CMMDS) of vSAN elects exactly one master node in every network partition. In a well formed cluster there is exactly one master, but when there are partition, each partition will have its own master. The master doesn't have any special user visible role, it is purely an internal state and any node can be master. The vSAN performance service uses the CMMDS Master node to establish its own notion of "Stats Master". Note though that to be "Stats master" it is not sufficient for a node to be CMMDS Master. The node must also have accessibility to the Stats DB object. Using this scheme guarantees that

- The Stats Master is easily discoverable.
- There is only ever one Stats Master in the cluster.

Stats master:
vSAN performance service is a distributed/clustered solution. Every host in a performance service enabled cluster is running a performance service instance. One host is elected to a master named as Stats Master. Stats Master is elected from CMMDS Master hosts only. The Stats Master is the only one writing to the DB. It periodically queries the performance service on the other members of the cluster, aggregates the results and persists them into the database. Stats Master is the host which can response APIs. Every request from front-end client will be handled by Stats Master.

Properties

Name | Type | Description
--- | --- | ---
error* | LocalizedMethodFault | If error is set, it means that collection of node information failed.
hostname* | xsd:string | Name of the host. Only set if queried via vCenter
isCmmdsMaster | xsd:boolean | Whether or not the node is CMMDS Master.
isStatsMaster | xsd:boolean | Whether or not the node is Stats Master.
masterInfo* | VsanPerfMasterInformation | Additional information in case the node is a stats master.
version | xsd:string | vSAN performance service version.
vsanMasterUuid* | xsd:string | The vSAN Node UUID of the CMMDS Master. May be itself.
vsanNodeUuid* | xsd:string | The vSAN Node UUID of the node being queried
Properties inherited from DynamicData
None

*Need not be set
Show WSDL type definition
<complexType xmlns="http://www.w3.org/2001/XMLSchema" xmlns:vsan="urn:vsan" name="VsanPerfNodeInformation"> <complexContent> <extension base="vsan:DynamicData"> <sequence> <element name="version" type="xsd:string"/> <element name="hostname" type="xsd:string" minOccurs="0"/> <element name="error" type="vsan:LocalizedMethodFault" minOccurs="0"/> <element name="isCmmdsMaster" type="xsd:boolean"/> <element name="isStatsMaster" type="xsd:boolean"/> <element name="vsanMasterUuid" type="xsd:string" minOccurs="0"/> <element name="vsanNodeUuid" type="xsd:string" minOccurs="0"/> <element name="masterInfo" type="vsan:VsanPerfMasterInformation" minOccurs="0"/> </sequence> </extension> </complexContent> </complexType>