Loop Broken? Am I going about this correctly? - powershell

Question

Trying to set up a loop that will run test_netconnection to each line in the text file and then output the response into a different file
I have tried different ways of writing it, just not sure where my loop breaks
$file = 'Z:\servers.txt'
$addresses = Get-Content $file
$reader = New-Object IO.Streamreader $file
while ($reader.ReadLine() -ne $null) { }
foreach ($address in $addresses) {
try {
$Test = Test-NetConnection -ComputerName $addresses -Port xxxx -InformationLevel Quiet
Write-Host "$Test"
}
catch {
Out-File z:/output.txt
}
}
Not getting any output sent to my Out-File, I suspect that my loop is broken

Answer 1

If servers.txt contains the following:
www.google.com
www.microsoft.com
www.stackoverflow.com
...
...then you can loop through it, use Test-NetConnection to see if entries are pingable (ICMP), and export the results as a *.CSV file with the following code:
$servers = Get-Content C:\path\to\servers.txt
$servers | % {
Test-NetConnection $_ | Select ComputerName, PingSucceeded | Export-Csv C:\path\to\results.csv -NoTypeInformation -Append
}
You can extend the exported result properties by adjusting the Select portion of the code.

Answer 2

here's a rather overdone version of the idea. [grin] it uses Tet-Connection instead of the newer Test-NetConnection since win7ps5.1 does not have that cmdlet.
if you nave never seen it used before, the #region comments are code folding markers. that lets one fold away the parts that are not currently of interest.
#region - save default prefs
# the Verbose default is screen display OFF
$AllowVerboseOutput = $True
# the Warning default is screen display ON
$AllowWarningOutput = $True
# save the VerbosePref
$OldVPref = $VerbosePreference
if ($AllowVerboseOutput)
{
# enable screen display of Write-Verbose [it's OFF by default]
$VerbosePreference = 'Continue'
}
# save the WarningPref
$OldWPref = $WarningPreference
if (-not $AllowWarningOutput)
{
# DISABLE Write-Warning screen output [it's ON by default]
$WarningPreference = 'SilentlyContinue'
}
#endregion - save default prefs
# if you want _fewer_ reports, use a larger final time unit
# minutes, hours, whatever suits your needs [*grin*]
$TimeStamp = Get-Date -Format 'yyyy-MM-dd_HH-mm-ss'
$SystemListDir = $env:TEMP
$SystemListFile = 'ServerList.txt'
$FullSystemListFile = Join-Path -Path $SystemListDir -ChildPath $SystemListFile
$ReportDir = $env:TEMP
# if you don't want multiple report files, comment OUT this line & UN-comment the line after it
$ReportFile = -join ('ConnectionRemport', '_-_', $TimeStamp, '.csv')
#$ReportFile = -join ('ConnectionRemport', '.csv')
$FullReportFile = Join-Path -Path $ReportDir -ChildPath $ReportFile
$NoResponse = '-- No Response --'
#region - sample data import
# fake reading in a file
# in real life, use the Get-Content line below
# remove the leading "#" on the next line when you are ready to use a real file
#<#
$SystemList = #'
LocalHost
127.0.0.1
10.0.0.1
'#.Split("`n").Trim()
#>
#endregion - sample data import
# remove the leading "#" on the next line when you are ready to use a real file
#$SystemList = Get-Content -Path $FullSystemListFile
$Results = foreach ($SL_Item in $SystemList)
{
Write-Verbose "Connecting to $SL_Item ..."
if (Test-Connection -ComputerName $SL_Item -Count 1 -Quiet)
{
Write-Verbose " System $SL_Item reached successfully."
$TempObject = [PSCustomObject]#{
MachineName = $SL_Item
Status = 'Online'
# the resulting "sortable" date string is yyyy-MM-ddTHH:mm:ss
TimeStamp = (Get-Date).ToString("s")
}
}
else
{
Write-Warning " Unable to reach $SL_Item."
$TempObject = [PSCustomObject]#{
MachineName = $SL_Item
Status = $NoResponse
# the resulting "sortable" date string is yyyy-MM-ddTHH:mm:ss
TimeStamp = (Get-Date).ToString("s")
}
}
$TempObject
} # end = foreach ($SL_Item in $SystemList)
# display $Results on screen
$Results
# save $Results to CSV file
$Results |
Export-Csv -LiteralPath $FullReportFile -NoTypeInformation
#region - restore default prefs
# restore previuos VerbosePref
$VerbosePreference = $OldVPref
# restore previous WarningPref
$WarningPreference = $OldWPref
#endregion - restore default prefs
on-screen output while running ...
VERBOSE: Connecting to LocalHost ...
VERBOSE: System LocalHost reached successfully.
VERBOSE: Connecting to 127.0.0.1 ...
VERBOSE: System 127.0.0.1 reached successfully.
VERBOSE: Connecting to 10.0.0.1 ...
WARNING: Unable to reach 10.0.0.1.
final onscreen output from the $Results collection ...
MachineName Status TimeStamp
----------- ------ ---------
LocalHost Online 2019-08-02T12:16:43
127.0.0.1 Online 2019-08-02T12:16:43
10.0.0.1 -- No Response -- 2019-08-02T12:16:47
CSV file content ...
"MachineName","Status","TimeStamp"
"LocalHost","Online","2019-08-02T12:16:43"
"127.0.0.1","Online","2019-08-02T12:16:43"
"10.0.0.1","-- No Response --","2019-08-02T12:16:47"