tests/Test-HostNetworkAccessibility.ps1

function Test-HostNetworkAccessibility {
    [CmdletBinding()]
    param (
        [parameter()][string] $TestName = "Network Port Accessibility",
        [parameter()][string] $TestGroup = "configuration",
        [parameter()][string] $Description = "Test open TCP ports",
        [parameter()][hashtable] $ScriptParams
    )
    try {
        $startTime = (Get-Date)
        # reference: https://docs.microsoft.com/en-us/mem/configmgr/core/plan-design/hierarchy/ports
        [string]$Setting = Get-CmHealthDefaultValue -KeySet "siteservers:tcpports" -DataSet $CmHealthConfig
        [System.Collections.Generic.List[PSObject]]$tempdata = @() # for detailed test output to return if needed
        $stat   = "PASS" # do not change this
        $except = "FAIL"
        $msg    = "No issues found" # do not change this either
        $ErrorActionPreference = 'SilentlyContinue'
        $counter = 0; $good = 0; $bad = 0
        foreach ($port in ($setting -split ',')) {
            Write-Verbose "testing port: $port"
            try {
                $conn = New-Object System.Net.Sockets.TcpClient($(hostname),$port)
                $tempdata.Add(
                    [pscustomobject]@{
                        Hostname = $(hostname)
                        Port     = $port
                        Status   = $conn.Connected
                    }
                )
                $good++
            }
            catch {
                $tempdata.Add(
                    [pscustomobject]@{
                        Hostname = $(hostname)
                        Port     = $port
                        Status   = "blocked"
                    }
                )
                $bad++
            }
            $counter++
        }
        if ($bad -gt 0) {
            $stat = $except
        }
    }
    catch {
        $stat = 'ERROR'
        $msg = $_.Exception.Message -join ';'
    }
    finally {
        Write-Output $([pscustomobject]@{
            TestName    = $TestName
            TestGroup   = $TestGroup
            TestData    = $tempdata
            Description = $Description
            Status      = $stat
            Message     = $msg
            RunTime     = $(Get-RunTime -BaseTime $startTime)
            Credential  = $(if($ScriptParams.Credential){$($ScriptParams.Credential).UserName} else { $env:USERNAME })
        })
    }
}