Configuration drift detection in PowerShell - Mini Project: Build & Apply

Configuration Drift Detection

📖 Scenario: You are a system administrator managing servers. You want to detect if any server's configuration has changed from the expected settings. This helps keep servers secure and consistent.

🎯 Goal: Create a PowerShell script that stores expected server configurations, sets a threshold for allowed differences, compares actual configurations to expected ones, and outputs any detected configuration drift.

📋 What You'll Learn

Create a dictionary of server names and their expected configuration values.

Add a threshold variable to define allowed difference count.

Write a loop to compare actual server configurations to expected ones and detect drift.

Print the list of servers with configuration drift.

💡 Why This Matters

🌍 Real World

System administrators use configuration drift detection to keep servers consistent and secure by spotting unexpected changes quickly.

💼 Career

This skill helps in roles like system administration, DevOps, and IT security where automation scripts maintain infrastructure health.

1

Create expected server configurations

Create a PowerShell hashtable called $expectedConfigs with these exact entries: 'ServerA' = 'v1.2', 'ServerB' = 'v1.3', 'ServerC' = 'v1.2'.

PowerShell

# Create the hashtable $expectedConfigs with the given server versions
# Your code here

Need a hint?

Use @{} to create a hashtable in PowerShell with key-value pairs separated by semicolons.

2

Add allowed drift threshold

Create a variable called $allowedDrift and set it to 0 to define the allowed number of configuration differences.

PowerShell

$expectedConfigs = @{ 'ServerA' = 'v1.2'; 'ServerB' = 'v1.3'; 'ServerC' = 'v1.2' }
# Create the variable $allowedDrift and set it to 0
# Your code here

Need a hint?

Just assign the number 0 to the variable $allowedDrift.

3

Detect configuration drift

Create a hashtable called $actualConfigs with these entries: 'ServerA' = 'v1.2', 'ServerB' = 'v1.4', 'ServerC' = 'v1.2'. Then, create an empty array called $driftedServers. Use a foreach loop with variable $server to iterate over $expectedConfigs.Keys. Inside the loop, compare $actualConfigs[$server] with $expectedConfigs[$server]. If they differ, add $server to $driftedServers.

PowerShell

$expectedConfigs = @{ 'ServerA' = 'v1.2'; 'ServerB' = 'v1.3'; 'ServerC' = 'v1.2' }
$allowedDrift = 0
# Create $actualConfigs hashtable with given entries
# Create empty array $driftedServers
# Use foreach loop with $server in $expectedConfigs.Keys
# Compare actual and expected configs
# If different, add $server to $driftedServers
# Your code here

Need a hint?

Use -ne to check if values are not equal. Use += to add items to an array.

4

Print detected drifted servers

Write a Write-Output statement to print the text 'Servers with configuration drift:'. Then write another Write-Output statement to print the $driftedServers array.

PowerShell

$expectedConfigs = @{ 'ServerA' = 'v1.2'; 'ServerB' = 'v1.3'; 'ServerC' = 'v1.2' }
$allowedDrift = 0
$actualConfigs = @{ 'ServerA' = 'v1.2'; 'ServerB' = 'v1.4'; 'ServerC' = 'v1.2' }
$driftedServers = @()
foreach ($server in $expectedConfigs.Keys) {
    if ($actualConfigs[$server] -ne $expectedConfigs[$server]) {
        $driftedServers += $server
    }
}
# Print the message and the list of drifted servers
# Your code here

Need a hint?

Use Write-Output to print text and variables in PowerShell.