PowerShell Loop Ping Online Status - powershell

Question

I'm trying to modify a Powershell to do the following work, but I got into some errors.
My goal is to monitor multiple servers online status from the the Powershell window. I would need to open a Powershell and run the ps1 script from the Powershell window then monitor the online status result.
1. Ping servers from a list from hostname.txt
2. If server pingable and online return hostname and ip in Green
3. If server timeout return hostname and ip in red
4. Loop back to the first server and ping again
Please help. Thank You !
$name=Get-content "c:\temp\hostname.txt"
foreach($name in $names) {
if(Test-Connection -ComputerName $name -Count 1 -ErrorAction SilentlyContinue) {
Write-Host "$name is up" -foregroundColor Green
$output+="$name is up,"+"'n"
}
else {
Write-Host "$name is up" -foregroundColor Red
$output+="$name is down,"+"'n"
}
}

Answer 1

Here's an old script I have called pinger that does something similar. It uses a hashtable, so it only reports changes in status, and sleeps a little at the end of the loop. It also beeps. If I output an object instead of text, there would be a delay until 2 objects were output.
# pinger.ps1
# example: pinger comp1
# pinger comp1,comp2,comp3
# $list = cat comps.txt; pinger $list
param ($hostnames)
$pingcmd = 'test-connection'
$sleeptime = 1
$sawup = #{}
$sawdown = #{}
foreach ($hostname in $hostnames) {
$sawup[$hostname] = $false
$sawdown[$hostname] = $false
}
while ($true) {
foreach ($hostname in $hostnames) {
if (& $pingcmd -count 1 $hostname -ea 0) {
if (! $sawup[$hostname]) {
echo "$([console]::beep(500,300))$hostname is up $(get-date)"
$sawup[$hostname] = $true
$sawdown[$hostname] = $false
}
} else {
if (! $sawdown[$hostname]) {
echo "$([console]::beep(500,300))$hostname is down $(get-date)"
$sawdown[$hostname] = $true
$sawup[$hostname] = $false
}
}
}
sleep $sleeptime
}
pinger microsoft.com,yahoo.com
microsoft.com is down 07/22/2021 09:55:15
yahoo.com is up 07/22/2021 09:55:15

Answer 2

If you want it to repeat in perpetuity, wrap the whole thing in a while($true){...} loop:
while($true){
$names = Get-content "c:\temp\hostname.txt"
foreach ($name in $names) {
if (Test-Connection -ComputerName $name -Count 1 -ErrorAction SilentlyContinue) {
Write-Host "$name is up" -foregroundColor Green
$output += "$name is up," + "'n"
}
else {
Write-Host "$name is up" -foregroundColor Red
$output += "$name is down," + "'n"
}
}
}
If you want to show the resolved IP address, make sure you save the output from Test-Connection to a variable:
if($ping = Test-Connection -ComputerName $name -Count 1 -ErrorAction SilentlyContinue){
Write-Host "$name [IP: $($ping.ProtocolAddress)] is up" -ForegroundColor Green
$output += "$name [IP: $($ping.ProtocolAddress)] is up `n"
}