This guide will help you to enable SSL on Solr so it can run over HTTPS.

1. Download and install JRE or JDK 8.0 or later version

• This will come with the Keytool.exe tool that will help us create the certificate

2. Download Solr 6.6.*-7.2.*

3. In the installation folder, find the etc folder. i.e.  C:\solr\solr-6.6.2\server\etc and create a PowerShell script.

• Make sure the that the Keytool.exe is pointing to your local JRE/JDK

param(
	[string]$KeystoreFile = 'solr-ssl.keystore.jks',
	[string]$KeystorePassword = 'secret',
	[string]$SolrDomain = 'localhost',
	[switch]$Clobber
)

$ErrorActionPreference = 'Stop'

### PARAM VALIDATION
if($KeystorePassword -ne 'secret') {
	Write-Error 'The keystore password must be "secret", because Solr apparently ignores the parameter'
}

if((Test-Path $KeystoreFile)) {
	if($Clobber) {
		Write-Host "Removing $KeystoreFile..."
		Remove-Item $KeystoreFile
	} else {
		$KeystorePath = Resolve-Path $KeystoreFile
		Write-Error "Keystore file $KeystorePath already existed. To regenerate it, pass -Clobber."
	}
}

$P12Path = [IO.Path]::ChangeExtension($KeystoreFile, 'p12')
if((Test-Path $P12Path)) {
	if($Clobber) {
		Write-Host "Removing $P12Path..."
		Remove-Item $P12Path
	} else {
		$P12Path = Resolve-Path $P12Path
		Write-Error "Keystore file $P12Path already existed. To regenerate it, pass -Clobber."
	}
}

try {
	$keytool = (Get-Command 'C:\Program Files\Java\jre1.8.0_144\bin\keytool.exe').Source
} catch {
	$keytool = Read-Host "keytool.exe not on path. Enter path to keytool (found in JRE bin folder)"

	if([string]::IsNullOrEmpty($keytool) -or -not (Test-Path $keytool)) {
		Write-Error "Keytool path was invalid."
	}
}

### DOING STUFF

Write-Host ''
Write-Host 'Generating JKS keystore...'
& $keytool -genkeypair -alias solr-ssl -keyalg RSA -keysize 2048 -keypass $KeystorePassword -storepass $KeystorePassword -validity 9999 -keystore $KeystoreFile -ext SAN=DNS:$SolrDomain,IP:127.0.0.1 -dname "CN=$SolrDomain, OU=Organizational Unit, O=Organization, L=Location, ST=State, C=Country"

Write-Host ''
Write-Host 'Generating .p12 to import to Windows...'
& $keytool -importkeystore -srckeystore $KeystoreFile -destkeystore $P12Path -srcstoretype jks -deststoretype pkcs12 -srcstorepass $KeystorePassword -deststorepass $KeystorePassword

Write-Host ''
Write-Host 'Trusting generated SSL certificate...'
$secureStringKeystorePassword = ConvertTo-SecureString -String $KeystorePassword -Force -AsPlainText
$root = Import-PfxCertificate -FilePath $P12Path -Password $secureStringKeystorePassword -CertStoreLocation Cert:\LocalMachine\Root
Write-Host 'SSL certificate is now locally trusted. (added as root CA)'

Write-Host ''
Write-Host '########## NEXT STEPS ##########' -ForegroundColor Green
Write-Host ''
Write-Host '1. Copy your keystore to $SOLR_HOME\server\etc (MUST be here)' -ForegroundColor Green

if(-not $KeystoreFile.EndsWith('solr-ssl.keystore.jks')) {
	Write-Warning 'Your keystore file is not named "solr-ssl.keystore.jks"'
	Write-Warning 'Solr requires this exact name, so make sure to rename it before use.'
}

$KeystorePath = Resolve-Path $KeystoreFile
Write-Host ''
Write-Host '2. Add the following lines to your solr.in.cmd:' -ForegroundColor Green
Write-Host ''
Write-Host "set SOLR_SSL_KEY_STORE=etc/solr-ssl.keystore.jks" -ForegroundColor Yellow
Write-Host "set SOLR_SSL_KEY_STORE_PASSWORD=$KeystorePassword" -ForegroundColor Yellow
Write-Host "set SOLR_SSL_TRUST_STORE=etc/solr-ssl.keystore.jks" -ForegroundColor Yellow
Write-Host "set SOLR_SSL_TRUST_STORE_PASSWORD=$KeystorePassword" -ForegroundColor Yellow
Write-Host ''
Write-Host 'Done!'

4. Open PowerShell and execute the script.

• This script will create the self-signed certificates required to enable SSL

5. In your Solr installation folder, go to the bin folder and open the solr.in.cmd file. Comment out the settings that relate to SSL (Ctrl + F to find the *_SSL_ entries).

If you want to install Solr as a service you can download the Non-Sucking Service Manager application and follow these instructions. 

1. Open the command prompt in Administrator mode and navigate where the nssm was installed. 
2. Execute install command in order to set up a new service
3. It will pop out a window where we need to fill some values
   • • Path: where solr.cmd was installed. C:\solr\solr-6.6.2\bin\solr.cmd
     • Startup directory: will be automatically filled in. 
     • Arguments: start -f -p 9693. Here we specify the port that we are going to use. In this case, we have set 9693 as our port. Make sure the port you use is available.  
   
4. Make sure your service is running. Browse to https://localhost:XXXX/solr/ where XXXX is the port number you have set. i.e. https://localhost:9693/solr/ and confirm it’s working.

And that’s it! You have Solr running over HTTPS. 

Happy Solring 😉