From 85d3137b14725171d76d42cf1c9319ff6aa0c2c0 Mon Sep 17 00:00:00 2001
From: Markus Fleschutz <markus@fleschutz.de>
Date: Sat, 20 Mar 2021 15:51:03 +0100
Subject: [PATCH] Add check-health.ps1

---
 Data/scripts.csv                              |  3 +-
 README.md                                     |  3 +-
 ...dns-cache.ps1 => check-dns-resolution.ps1} |  8 ++---
 Scripts/check-drive-space.ps1                 | 12 +++----
 Scripts/check-health.ps1                      | 36 +++++++++++++++++++
 5 files changed, 50 insertions(+), 12 deletions(-)
 rename Scripts/{train-dns-cache.ps1 => check-dns-resolution.ps1} (69%)
 create mode 100755 Scripts/check-health.ps1

diff --git a/Data/scripts.csv b/Data/scripts.csv
index b6a4456a..c8968064 100644
--- a/Data/scripts.csv
+++ b/Data/scripts.csv
@@ -1,6 +1,8 @@
 Script,Description
 add-firewall-rules.ps1, adds firewall rules to the given executables (requires admin rights)
+check-dns-resolution.ps1, checks the DNS resolution with frequently used domain names
 check-drive-space.ps1, checks the given drive for free space left
+check-health.ps1, checks the system health
 check-ipv4-address.ps1, checks the given IPv4 address for validity
 check-ipv6-address.ps1, checks the given IPv6 address for validity
 check-mac-address.ps1, checks the given MAC address for validity
@@ -127,7 +129,6 @@ switch-branch.ps1, switches the branch in the current/given Git repository (incl
 switch-shelly1.ps1, switches a Shelly1 device in the local network
 take-screenshot.ps1, takes a single screenshot
 take-screenshots.ps1, takes multiple screenshots
-train-dns-cache.ps1, trains the DNS cache with frequently used domain names
 translate-text.ps1, translates the given text into other languages
 turn-volume-up.ps1, turns the audio volume up (+10% by default)
 turn-volume-down.ps1, turns the audio volume down (-10% by default)
diff --git a/README.md b/README.md
index dd4160ae..d1f06ddb 100644
--- a/README.md
+++ b/README.md
@@ -30,7 +30,9 @@ Collection of PowerShell Scripts
 ⚙️ Scripts for Computer Management
 ---------------------------------
 * [add-firewall-rules.ps1](Scripts/add-firewall-rules.ps1) - adds firewall rules for the given executables (requires admin rights)
+* [check-dns-resolution.ps1](Scripts/check-dns-resolution.ps1) - checks the DNS resolution with frequently used domain names
 * [check-drive-space.ps1](Scripts/check-drive-space.ps1) - checks the given drive for free space left
+* [check-health.ps1](Scripts/check-health.ps1) - checks the system health
 * [check-swap-space.ps1](Scripts/check-swap-space.ps1) - checks the swap space for free space left
 * [check-windows-system-files.ps1](Scripts/check-windows-system-files.ps1) - checks the validity of the Windows system files (requires admin rights)
 * [enable-crash-dumps.ps1](Scripts/enable-crash-dumps.ps1) - enables the writing of crash dumps
@@ -158,7 +160,6 @@ Collection of PowerShell Scripts
 * [simulate-matrix.ps1](Scripts/simulate-matrix.ps1) - simulates the Matrix (fun)
 * [simulate-presence.ps1](Scripts/simulate-presence.ps1) - simulates the human presence against burglars
 * [switch-shelly1.ps1](Scripts/switch-shelly1.ps1) - switches a Shelly1 device in the local network
-* [train-dns-cache.ps1](Scripts/train-dns-cache.ps1) - trains the DNS cache with frequently used domain names
 * [translate-text.ps1](Scripts/translate-text.ps1) - translates the given text into other languages
 * [weather.ps1](Scripts/weather.ps1) - prints the current weather forecast
 * [weather-alert.ps1](Scripts/weather-alert.ps1) - checks the current weather for critical values
diff --git a/Scripts/train-dns-cache.ps1 b/Scripts/check-dns-resolution.ps1
similarity index 69%
rename from Scripts/train-dns-cache.ps1
rename to Scripts/check-dns-resolution.ps1
index 10b93150..e682e98a 100755
--- a/Scripts/train-dns-cache.ps1
+++ b/Scripts/check-dns-resolution.ps1
@@ -1,7 +1,7 @@
 #!/bin/powershell
 <#
-.SYNTAX         ./train-dns-cache.ps1
-.DESCRIPTION	trains the DNS cache with frequently used domain names
+.SYNTAX         ./check-dns-resolution.ps1
+.DESCRIPTION	checks the DNS resolution with frequently used domain names
 .LINK		https://github.com/fleschutz/PowerShell
 .NOTES		Author:	Markus Fleschutz / License: CC0
 #>
@@ -18,14 +18,14 @@ try {
 
 	foreach($Row in $Table) {
 		$Domain = $Row.Domain
-		write-progress "Training DNS cache with $Domain..."
+		write-progress "Resolving $Domain..."
 		$Ignore = nslookup $Domain
 	}
 
 	$Count = $Table.Length
 	$StopTime = Get-Date
 	$TimeInterval = New-Timespan -start $StartTime -end $StopTime
-	write-host -foregroundColor green "Done - DNS cache trained with $Count domain names in $TimeInterval seconds"
+	write-host -foregroundColor green "OK - resolved $Count domain names in $TimeInterval seconds"
 	exit 0
 } catch {
 	write-error "ERROR: line $($_.InvocationInfo.ScriptLineNumber): $($Error[0])"
diff --git a/Scripts/check-drive-space.ps1 b/Scripts/check-drive-space.ps1
index c0c6381d..034ecd00 100755
--- a/Scripts/check-drive-space.ps1
+++ b/Scripts/check-drive-space.ps1
@@ -14,15 +14,15 @@ if ($Drive -eq "" ) {
 
 try {
 	$DriveDetails = (get-psdrive $Drive)
-	[int]$FreeSpace = (($DriveDetails.Free / 1024) / 1024) / 1024
-	[int]$InUse = (($DriveDetails.Used / 1024) / 1024) / 1024
-	[int]$Total = ($InUse + $FreeSpace)
+	[int]$Free = (($DriveDetails.Free / 1024) / 1024) / 1024
+	[int]$Used = (($DriveDetails.Used / 1024) / 1024) / 1024
+	[int]$Total = ($Used + $Free)
 
-	if ($FreeSpace -lt $MinLevel) {
-        	write-warning "Drive $Drive has only $FreeSpace GB left to use! ($InUse GB out of $Total GB in use, minimum is $MinLevel GB)"
+	if ($Free -lt $MinLevel) {
+        	write-warning "Drive $Drive has only $Free GB left to use! ($Used GB out of $Total GB in use, minimum is $MinLevel GB)"
 		exit 1
 	}
-	write-host -foregroundColor green "OK - drive $Drive has $FreeSpace GB left to use ($InUse GB out of $Total GB in use, minimum is $MinLevel GB)"
+	write-host -foregroundColor green "OK - $Free GB free at drive $Drive ($Used GB used out of $Total GB, $MinLevel GB is minimum)"
 	exit 0
 } catch {
 	write-error "ERROR: line $($_.InvocationInfo.ScriptLineNumber): $($Error[0])"
diff --git a/Scripts/check-health.ps1 b/Scripts/check-health.ps1
new file mode 100755
index 00000000..4867b74b
--- /dev/null
+++ b/Scripts/check-health.ps1
@@ -0,0 +1,36 @@
+#!/bin/powershell
+<#
+.SYNTAX         ./check-health.ps1 
+.DESCRIPTION	checks the system health
+.LINK		https://github.com/fleschutz/PowerShell
+.NOTES		Author:	Markus Fleschutz / License: CC0
+#>
+
+try {
+	$Hostname = $(hostname)
+	"Checking health of $Hostname ..."
+
+	& check-swap-space.ps1
+	if ($lastExitCode -ne "0") { throw "check-swap-space.ps1 failed" }
+
+	if ($IsLinux) {
+		& check-drive-space.ps1 /
+	} else {
+		& check-drive-space.ps1 C
+	}
+	if ($lastExitCode -ne "0") { throw "check-drive-space.ps1 failed" }
+
+	if (-not($IsLinux)) {
+		& check-windows-system-files.ps1
+		if ($lastExitCode -ne "0") { throw "check-windows-system-files.ps1 failed" }
+	}
+
+	& check-dns-resolution.ps1
+	if ($lastExitCode -ne "0") { throw "check-dns-resolution.ps1 failed" }
+
+	write-host -foregroundColor green "OK - $Hostname is healthy"
+	exit 0
+} catch {
+	write-error "ERROR: line $($_.InvocationInfo.ScriptLineNumber): $($Error[0])"
+	exit 1
+}