Powershell script while writing to AWS Cloudwatch throws error - Write-CWMetricData :

Question

We are using Microsoft HPC (High performance computing). When a job is running, I want to see various HPC metrics and publish them onto AWS Cloudwatch. Below is the script that was on AWS site. Entire script runs fine but the last line which tries to write to Cloudwatch fails.

Did anyone get this error?

Write-CWMetricData : A WebException with status NameResolutionFailure was thrown.
   At D:\temp\HPCMetricstest.ps1:81 char:1
   + Write-CWMetricData -Namespace "HPC Cluster Metrics" -MetricData $m1, 
    $m2, $m3, $ ...

     + CategoryInfo          : InvalidOperation: 
(Amazon.PowerShe...etricDataCmdlet:WriteCWMetricDataCmdlet) [Write-CWM
        etricData], InvalidOperationException
  + FullyQualifiedErrorId :mazon.Runtime.AmazonServiceException,Amazon.PowerShell.Cmdlets.CW.WriteCWMetricDataCmdl
   et


  # 
  # This PowerShell script computes metrics on the head node of an HPC 
   Pack cluster and publishes them to Amazon CloudWatch 
  #
  # It must be called with the current region and stack name
   #  Properties of HPC Nod: NetBiosName, HealthState, State, Groups 
  [CmdletBinding()]
  param(
        [Parameter(Mandatory=$True,Position=1)]
        [string]$Region,
        [Parameter(Mandatory=$True,Position=2)]
        [string]$Stack
  )

   Add-PSSnapIn Microsoft.HPC
   Import-Module AWSPowerShell


    $jobs = (Get-HpcJob -State Queued, Running -ErrorAction SilentlyContinue)

    $tasks = ($jobs | Get-HpcTask -State Running, Queued -ErrorAction SilentlyContinue)
    $nodes = (Get-HpcNode -GroupName ComputeNodes -State Online)

    $jobCount = $jobs.Count
    $taskCount = $task.Count
    $coreHours = ($tasks | % { $_.Runtime.TotalHours * $_.MinCores } | 
    Measure-Object -Sum | Select-Object -ExpandProperty Sum)
    $nodeCount = $nodes.Count


    $coresPerMachine = ($nodes | Measure-Object -Property SubscribedCores -Average | Select-Object -ExpandProperty Average)

    Write-Host "Cores per machine basam " $coresPerMachine

    $machineHours = [System.Math]::Ceiling($coreHours / $coresPerMachine)
    $globalHours = [System.Math]::Ceiling($machineHours / $nodeCount)

    Function CreateMetric
    {
          param([string]$Name, [string]$Unit="Count", [string]$Value="0", 
          [string]$StackId, [System.DateTime]$When = (Get-
          Date).ToUniversalTime())

          $dim = New-Object Amazon.CloudWatch.Model.Dimension
          $dim.Name = "StackId"
         $dim.Value = $StackId

$dat = New-Object Amazon.CloudWatch.Model.MetricDatum
$dat.Timestamp = $When
$dat.MetricName = $Name
$dat.Unit = $Unit
$dat.Value = $Value

#Write-Host $dat.MetricName $dat.Value $dat.Unit $dat.Timestamp

$dat.Dimensions = New-Object -TypeName System.Collections.Generic.List[Amazon.CloudWatch.Model.Dimension]
$dat.Dimensions.Add($dim)
$dat
}

   $now = (Get-Date).ToUniversalTime()
   $m1 = (CreateMetric -Name "Job Count" -Value "$jobCount" -StackId 
        $Stack -When $now)
   $m2 = (CreateMetric -Name "Task Count" -Value "$taskCount" -StackId 
       $Stack -When $now)
    $m3 = (CreateMetric -Name "Core Hours" -Value "$coreHours" -StackId 
         $Stack -When $now)
    $m4 = (CreateMetric -Name "Node Count" -Value "$nodeCount" -StackId 
         $Stack -When $now)
     $m5 = (CreateMetric -Name "Cores Per Machine" -Value 
         "$coresPerMachine" -StackId $Stack -When $now)
      $m6 = (CreateMetric -Name "Machine Hours" -Value "$machineHours" -
        StackId $Stack -When $now)
      $m7 = (CreateMetric -Name "Global Hours" -Value "$globalHours" -
         StackId $Stack -When $now)

      #Next line I am getting issue   
      Write-CWMetricData -Namespace "HPC Cluster Metrics" -MetricData 
          $m1, $m2, $m3, $m4, $m5, $m6, $m7 -Region $Region

score 1 · Answer 1 · answered Sep 22 '17 at 21:38

1

In the AWS Tools for PowerShell, "A WebException with status NameResolutionFailure was thrown." often means that you've specified the region incorrectly. This is because the region is used to resolve DNS for the backing web service you're trying to hit, in this case the CloudWatch service for your given region.

See the documentation for a list of valid regions, or comment here with the region you attempted to use and we can help you pick the right one.

Powershell script while writing to AWS Cloudwatch throws error - Write-CWMetricData :

1 Answers1

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