Automated Host creation and deployment
Zabbix is a powerful open-source monitoring solution that can monitor various services, servers, and network devices. In this blog, I will show how I setup WMI sensor discovery with auto-deployment of the Zabbix Agent using GPO, and having the desktops auto-register with the Zabbix server.
‣ Prerequisites
• Zabbix Server
• Windows Server
Host Creation
SENSOR DISCOVERY
This part sets up how I will get sensor information from LibreHardwareMonitor and send it to Zabbix. The purpose is to install the Zabbix Agent on select Windows machines that need more monitoring than most.
First, I opened up Visual Studio Code and made the following YAML file to extract WMI information from LibreHardwareMonitor.
zabbix_export:
version: '6.4'
template_groups:
- uuid: 57b7ae836ca64446ba2c296389c00933
name: Templates/Modules
- uuid: 846977d1dfed4968bc5f8bdb36328533
name: 'Templates/Operating systems'
templates:
- uuid: f4c4ad00160d4848bb6e8d4f4aa83033
template: WINDOWS_LHM_AUTO
name: 'Windows LibreHardwareMonitor Discovery'
groups:
- name: Templates/Modules
- name: 'Templates/Operating systems'
discovery_rules:
- uuid: 82ce8718123a4613866b5ce90c38f933
name: 'Sensors discovery'
key: lhm_discovery
filter:
conditions:
- macro: '{#ID_WMI}'
formulaid: A
type: ZABBIX_ACTIVE
item_prototypes:
- uuid: 0ad541b0a61a476a867e5d1ae03fc333
name: 'LHM: {#NAME_WMI}'
key: 'Lhm_capteur[{#ID_WMI}]'
value_type: FLOAT
type: ZABBIX_ACTIVE
template_groups– This will add it to the ‘Templates/Modules’ and ‘Templates/Operating systems’ groups.templates– This will give it the name ‘Windows LibreHardwareMonitor Discovery’.discovery_ruleslhm_discovery– The item key used by Zabbix to execute this discovery.{#ID_WMI}Contains conditions that refine which discovered entities are considered valid.ZABBIX_ACTIVE– Specifies that this is an active check, meaning the agent sends data to the server.
I then went to Data Collection > Templates.
Then selected the file and clicked ‘Import’.
AUTO-REGISTRATION
This part shows how I setup auto-registration, that way any Active Agents will be automatically added to the host list, and be given the desired templates.
First, I went to Alerts > Actions > Autoregistration Actions.
I gave the action a name and clicked ‘Add’ under ‘Conditions’.
Each desktop ends with ‘PC’ so I set it up to add any host name that contact ‘PC’.
I then created an operation to add the host to the ‘Corporate Desktops’ group.
I also set it to add the templates ‘Windows by Zabbix agent active’ and the one I just created ‘Windows LibreHardwareMonitor Discovery’.
I then clicked ‘Add’.
WINDOWS SERVER
FILE PREPARATION
Here I go over downloading the necessary files, as well as creating a configuration file, and 2 PowerShell scripts, which will be used to get sensor information from LibreHardwareMonitor.
First, from my Windows Server I downloaded the Zabbix Agent 2 MSI installer.
https://www.zabbix.com/download_agents
I made sure to get the ‘agent 2’ MSI.
I then downloaded LibreHardwareMonitor.
https://github.com/LibreHardwareMonitor/LibreHardwareMonitor/releases
I then extracted the contents and created the following file and named it LibreHardwareMonitor.config
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<appSettings>
<add key="startMinMenuItem" value="true" />
<add key="minCloseMenuItem" value="true" />
<add key="minTrayMenuItem" value="true" />
</appSettings>
</configuration>
startMinMenuItem– Makes the program start minimized upon boot.minCloseMenuItem– If you close the program it’ll minimize it to the system tray.minTrayMenuItem– If you minimize the program it’ll minimize it to the system tray.
I then created a PowerShell script to collect hardware sensor information from LibreHardwareMonitor via WMI, process it to create human-readable names, and then output the data in a JSON format suitable for Zabbix.
I named the file ‘lhm_discovery.ps1’.
#Create the data array
$sensorData = @()
Get-WmiObject -Namespace "Root\LibreHardwareMonitor" -Query "SELECT * FROM Sensor" | ForEach-Object {
#Make a human readable name for Zabbix
$blah = $_.Identifier -match '(\w+)/(\d+)$'
$itemPropertyName = (Get-Culture).TextInfo.ToTitleCase($Matches[1])
$itemPropertyIndex = $Matches[2]
#Create the object and populate its properites
$properties = @{'{#ID_WMI}'=$_.Identifier;'{#NAME_WMI}'=$_.Name + " " + $itemPropertyName + " " + $itemPropertyIndex}
$object = New-Object -TypeName PSObject -Prop $properties
#Add the object to the array
$sensorData += ($object)
}
#Wrap the resulting array into another object as property 'data'
$properties = @{'data'=$sensorData}
$object = New-Object -TypeName PSObject -Prop $properties
#Output to the console to be picked up by Zabbix
write-host($object | convertto-json)
\$sensorData = @()– Creates an empty array to store sensor data objects.Get-WmiObject– Queries WMI for all sensor objects in the LibreHardwareMonitor namespace.ForEach-Object– Processes each sensor.\$_.Identifier -match '(\w+)/(\d+)$'– Uses a regular express to extract two parts from the sensor’s Identifier property.(\w+)– Represents a type or category.(\d+)– Represents an index or identifier number.
I then created a PowerShell script to retrieve a specific sensor’s value from LibreHardwareMonitor using WMI, based on an identifier passed in by the Zabbix agent.
I named the file ‘lhm_get.ps1’.
#grab the ident parameter that was passed in (by the Zabbix agent)
param([string]$ident)
$request = "SELECT * FROM Sensor WHERE Identifier='$ident'"
#Request the data (only need the first result) and write it out to the console for the zabbix agent
$sensorValues = Get-WmiObject -Namespace "Root\LibreHardwareMonitor" -Query $request
write-host($sensorValues.value)
#Sample to test if it works
#powershell.exe -Noprofile -ExecutionPolicy Bypass -file "C:\Program Files\Zabbix Agent\lhm_discovery.ps1"
#Copy any #ID_WMI value in the and for example
#powershell.exe -Noprofile -ExecutionPolicy Bypass -file "C:\Program Files\Zabbix Agent\lhm_get.ps1" "/amdcpu/0/load/0"
NETWORK SHARE
I next needed to create a network share so that the computers can access these newly downloaded and created files.
First, I went to File and Storage Services > Volumes > Tasks > New Share.
Chose SMB Share - Quick.
I chose the server, and entered the custom path.
I gave the share the name ‘Zabbix’.
I checked both Enable access-based enumeration and Allow caching of share.
I added ‘Domain Users’ to have ‘Read & execute’ permissions.
Then clicked ‘Create’.
I created a folder within the share called ‘Zabbix’.
I then pasted the LHM folder (with the config file), the 2 PowerShell scripts I created and the Zabbix Agent 2 msi.
GROUP POLICY
I made seperate GPO’s, as well as different PowerShell scripts to install Zabbix, as well as Install LibreHardwareMonitor.
It’s possible that this all could have been accomplished with 1 script, but I could not figure it out myself. I kept running into errors and issues where it would start 3 instances of LibreHardwareMonitor.
The first GPO will be to install Zabbix.
I opened Group Policy Management, right-clicked on my domain and selected ‘Create a GPO in this domain, and Link it here…’.
I gave it an easy identifiable name.
Then right-clicked on the GPO and selected ‘Edit’.
I then drilled down to Computer Configuration > Policies > Windows Settings > Scripts.
I right-clicked ‘Startup’ and clicked ‘Properties’.
I clicked on the PowerShell Scripts tab, and then clicked on ‘Show Files’.
I’m going to create 4 ps1 files. So I right-clicked and went to New > Text Document.
First one will install Zabbix.
# Construct the FQDN of the local computer
$FQDN=(Get-WmiObject win32_computersystem).DNSHostName+"."+(Get-WmiObject win32_computersystem).Domain
$ZabbixInstallationMSI = "\\WIN-SVR1\Zabbix\Zabbix\zabbixagent2.msi"
$ZabbixAgentVersion = "7.2"
$ZabbixServerIP = "10.33.99.30"
$ZabbixInstallationFolder = "\\$FQDN\c$\Program Files\Zabbix Agent 2\"
$ZabbixSoftwareName = "Zabbix Agent 2 (64-bit)"
$InstalledZabbixVersion = (Get-WmiObject -Class Win32_Product | Where-Object { $_.Name -eq $ZabbixSoftwareName }).Version
# Extract the major version from the installed version
$InstalledVersion = $InstalledZabbixVersion -replace "(\d+\.\d+\.\d+).*", '$1'
$Arguments = "SERVER=$ZabbixServerIP SERVERACTIVE=$ZabbixServerIP HOSTMETADATA=Windows HOSTNAME=$FQDN /qn"
if ($InstalledVersion -lt $ZabbixAgentVersion) {
# The installed version if different from the desired version, so perform the installation or update
if (Test-Path $ZabbixInstallationMSI) {
# The instalation file is available, so start the installation process
Start-Process -FilePath "$ZabbixInstallationMSI" -ArgumentList "$Arguments" -Wait
# Copy-Item -Path @($ZabbixPluginFolder, $ZabbixScriptsFolder) -Destination $ZabbixInstallationFolder -Force -Recurse
} else {
# The installation file is not available, exit the script
exit
}
}
Next one is to move the 2 PowerShell scripts I created earlier, lhm_discovery & lhm_get, into the Zabbix folder.
$sourcePath = "\\WIN-SVR1\Zabbix\Zabbix\"
$destinationPath = "C:\Program Files\Zabbix Agent 2"
$files = @("lhm_discovery.ps1", "lhm_get.ps1")
foreach ($file in $files) {
$src = Join-Path -Path $sourcePath -ChildPath $file
$dest = Join-Path -Path $destinationPath -ChildPath $file
if (Test-Path $src) {
Copy-Item -Path $src -Destination $dest -Force
} else {
Write-Output "File not found: $src"
}
}
This next one will add 2 lines to the Zabbix configuration file. These 2 lines will work with the PowerShell scripts, lhm_discovery & lhm_get.
Set-ExecutionPolicy Unrestricted -Scope Process
$confFilePath = "C:\Program Files\Zabbix Agent 2\zabbix_agent2.conf"
$line1 = 'UserParameter=ohm_discovery,powershell.exe -Noprofile -ExecutionPolicy Bypass -file "C:\Program Files\Zabbix Agent 2\lhm_discovery.ps1"
$line2 = 'UserParameter=ohm_capteur[*],powershell.exe -Noprofile -ExecutionPolicy Bypass -file "C:\Program Files\Zabbix Agent 2\lhm_get.ps1" $1'
if (Test-Path $confFilePath) {
$configContent = Get-Content $confFilePath
if ($configContent -notcontains $line1) {
$configContent += $line1
}
if ($configContent -notcontains $line2) {
$configContent += $line2
}
$configContent | Set-Content -Path $confFilePath -Encoding Ascii -Force
}
Last one is to restart Zabbix, that way the Zabbix agent will start sending the LibreHardwareMonitor sensor information pulled with the PowerShell scripts.
Restart-Service -Name "Zabbix Agent 2"
I then created another GPO, and created the following PowerShell script to install LibreHardwareMonitor.
Get-Process -Name "LibreHardwareMonitor" -ErrorAction SilentlyContinue | Stop-Process -Force
New-Item -Path "C:\Program Files\" -Name "LHM" -ItemType Directory -Force
$sourceFolder = "\\WIN-SVR1\Zabbix\Zabbix\LHM\*"
$destinationFolder = "C:\Program Files\LHM"
$exePath = "C:\Program Files\LHM\LibreHardwareMonitor.exe"
Start-Sleep -Seconds 60
if (Test-Path "\\WIN-SVR1\Zabbix\Zabbix\LHM\") {
Copy-Item -Path $sourceFolder -Destination $destinationFolder -Recurse -Force
} else {
Write-Output "Error1"
exit
}
if (-Not (Test-Path $exePath)) {
Write-Output "Error2"
exit
}
$ohmRunning = Get-Process | Where-Object {
$_.Path -eq $exePath
}
if (-not $lhmRunning) {
Start-Process -FilePath $exePath
Write-Output "Error3"
} else {
Write-Output "Error4"
}