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Cluster Probe - discovery mechanism

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Article ID: 201276

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Updated On:

Products

DX Unified Infrastructure Management (Nimsoft / UIM)

Issue/Introduction

We are having an issue with with the cluster probe on a Microsoft SQL cluster, when the probe starts up for the first time it is discovering an incorrect cluster / nodes.  We have never seen this before, but suspect an issue with the cluster itself. What we want to understand is what mechanism the probe uses to discover the cluster config?  i.e. does it run specific cluster commands or use / run cluster failover manager or dll's etc

Environment

Release : 8.51

Component : UIM - CLUSTER

Resolution

The cluster probe runs specific commands to get the cluster details like Cluster Name, Nodes, Groups, etc.

For a Microsoft Cluster, the cluster probe uses APIs like GetClusterInformation, OpenClusterNode, ClusterOpenEnum, etc while discovering the Cluster name & Node details. (uses clusapi.h).

From the problem being reported in this case, it appears that the wrong node IP was being picked up after discovery by the cluster probe.

The node/machine has multiple IPs and the robotip is set for the nodes.

Yet, when the cluster probe starts for the first time if it doesn't always consistently pick the correct IP address based on the Cluster NIC configs, so to workaround this, the customer sets the node IP in the Cluster probe after it has started.