NLB detected a duplicate host priority that is shared between cluster hosts

Microsoft.Windows.NetworkLoadBalancing.2008.NLB.detected.a.duplicate.host.priority.that.is.shared.between.cluster.hosts (Rule)

Knowledge Base article:

Summary

Hosts in a Network Load Balancing (NLB) cluster are configured to load balance network traffic. Host configuration is set by using NLB Manager, and if it is not configured properly, the NLB cluster may not function correctly.

Resolutions

Ensure that all NLB hosts have unique host priorities

If a Network Load Balancing (NLB) host has a host priority that is identical to the host priority on another host, or the host priority is not valid, the cluster will not converge until the problem is corrected. The host priority must be a number from 1 through 32, and this value must be unique for all hosts in the cluster.

To ensure that all NLB hosts have a unique host priority:

Element properties:

TargetMicrosoft.Windows.NetworkLoadBalancing.2008.ServerRole
CategoryAlert
EnabledTrue
Alert GenerateFalse
RemotableTrue

Member Modules:

ID Module Type TypeId RunAs 
DS DataSource Microsoft.Windows.NetworkLoadBalancing.EventProvider Default
WA WriteAction Microsoft.Windows.NetworkLoadBalancing.2008.GenerateAlert.SuppressByDescription Default
WriteToDB WriteAction Microsoft.Windows.NetworkLoadBalancing.2008.CollectEvent Default

Source Code:

<Rule ID="Microsoft.Windows.NetworkLoadBalancing.2008.NLB.detected.a.duplicate.host.priority.that.is.shared.between.cluster.hosts" Enabled="onEssentialMonitoring" Target="Microsoft.Windows.NetworkLoadBalancing.2008.ServerRole" ConfirmDelivery="true" Remotable="true" Priority="Normal" DiscardLevel="100">
<Category>Alert</Category>
<DataSources>
<DataSource ID="DS" TypeID="NLBLibrary!Microsoft.Windows.NetworkLoadBalancing.EventProvider">
<Criteria>
<SimpleExpression>
<ValueExpression>
<XPathQuery>EventDisplayNumber</XPathQuery>
</ValueExpression>
<Operator>Equal</Operator>
<ValueExpression>
<Value>17</Value>
</ValueExpression>
</SimpleExpression>
</Criteria>
</DataSource>
</DataSources>
<WriteActions>
<WriteAction ID="WA" TypeID="Microsoft.Windows.NetworkLoadBalancing.2008.GenerateAlert.SuppressByDescription">
<Priority>1</Priority>
<Severity>2</Severity>
<AlertMessageId>$MPElement[Name="Microsoft.Windows.NetworkLoadBalancing.2008.NLB.detected.a.duplicate.host.priority.that.is.shared.between.cluster.hosts.AlertMessage"]$</AlertMessageId>
<EnableAlert>true</EnableAlert>
</WriteAction>
<WriteAction ID="WriteToDB" TypeID="Microsoft.Windows.NetworkLoadBalancing.2008.CollectEvent">
<CollectEvent>false</CollectEvent>
</WriteAction>
</WriteActions>
</Rule>