Use Windows Zabbix agent as lightweight "proxy"

[troffasky]

Scenario:
Central Site with only Windows VMs. Customer does not want to pay for a Linux VM to run Zabbix proxy on.
Remote sites VPN tunnel to here. No servers at remote sites.
Requirement: monitor connectivity between remote sites and central site.

I am sure others have faced a similar scenario. I assume I can create plenty of custom items on 1 agent at Central Site that do something simple like ping a remote device 10 times and take an average.
But is there a way to script/automate this to minimise the amount of manual fiddling about?

[Viktors Fomics]

Hello

If only ping monitoring is required, a scheduled PowerShell script can be set up to regularly ping all target devices and store the results as JSON. Afterwards a custom UserParameter in the agent can be created to read that JSON and send it to Zabbix server to be used as the master item; from this master item dependent items can be created with the help of JSONPath peprocessing to get metrics (like average latency or packet loss) for each device.

[Viktors Fomics]

If going a bit into details here, the motivation for a solution of that type is that using just UserParameter directly can result in timeouts, as every ping takes some time, so doing this part externally as a scheduled task would make sense. The list of hosts could be stored in a separate file (targets.txt in the example script below) that is accessible for the script and the script itself would look approximately like this:

$jsonFile = "C:\Zabbix\scripts\ping_results.json"
$hostsFile = "C:\Zabbix\scripts\targets.txt"

$hosts = Get-Content $hostsFile | Where-Object { $_ -and $_ -notmatch '^\s*$' }
$results = @()

foreach ($host in $hosts) {
$ping = Test-Connection -ComputerName $host -Count 4 -ErrorAction SilentlyContinue
if ($ping) {
$avg = ($ping | Measure-Object ResponseTime -Average).Average
$min = ($ping | Measure-Object ResponseTime -Minimum).Minimum
$max = ($ping | Measure-Object ResponseTime -Maximum).Maximum
$loss = 100 - (($ping.Count / 4) * 100)
} else {
$avg = $null
$min = $null
$max = $null
$loss = 100
}

$results += [PSCustomObject]@{
host = $host
avg_latency = [math]::Round($avg,2)
min_latency = $min
max_latency = $max
packet_loss = $loss
}
}

$results | ConvertTo-Json | Set-Content -Path $jsonFile -Force

So as a result there will be the required json file, which can be sent to Zabbix server with the following UserParameter=ping.json,Get-Content "C:\Zabbix\scripts\ping_results.json", this agent item with key ping.json would be the master item containing all JSON content, a dependant item can be derived from it with the help of JSONPath preprocessing step. Assuming JSON file's contents will be something like this: [{"host":"10.1.1.1","avg_latency":2.3,"packet_lo ss" :0},
{"host":"10.1.2.1","avg_latency":5.1,"packet_lo ss" :0}], the JSONPath expression to get the first host's average latency would be: $[?(@.host == '10.1.1.1')].avg_latency.first().